What solders are used for soldering?

Solder for soldering copper, aluminum, brass, steel, stainless steel. Composition of solder for soldering. Types of solders for soldering

When it is necessary to reliably fasten various solid connections together, soldering is most often chosen for this. This process is widespread in many industries. Home craftsmen also have to solder.

This operation helps not only when the TV or computer has failed, and to restore it it is necessary to replace the burnt microcircuit or chip. Using this process, refrigeration equipment and industrial systems are restored. Soldering helps if you need to get a tight connection.

In addition, some materials simply cannot be combined in any other way. Aluminum, copper, and brass cannot be joined by welding.

In order to obtain a high-quality and reliable, as well as hermetically sealed connection, you need to have not only good equipment and special skills, but also suitable consumables - solders and fluxes for soldering.

Solder alloys and types of flux are selected depending on the materials with which you will have to work. For example, when working with aluminum products, a different flux is needed than what is suitable for copper or silver. Below we will look at the main characteristics of each of them and choose the best option for the job.

Various metal alloys are used as it. There are also compositions based on pure metal. In order to create high-quality connections using one or another solder, these materials must differ in certain qualities.

Wettability

First of all, any type of solder must have excellent wettability. Without this characteristic, the parts being soldered simply will not be able to reliably contact each other. What is wettability? This is such an interesting phenomenon when the strength of the bonds between the particles of a solid and a liquid is higher than that of the molecules of the liquid.

If there is wettability, then the liquid will spread over the surface and enter all cavities. So, if solder solder does not wet copper, for example, then it cannot be used on that metal. Pure lead is not used for soldering.

Its wetting characteristics are very poor and high quality joints cannot be counted on.

Melting temperature

Whatever the type of solder, the temperature at which it begins to melt must necessarily be below the melting point of the materials being soldered. It should also be higher than the operating temperatures of the parts.

When we talk about melting point, we mean two points. This is the value at which low-melting components will begin the melting process, and the minimum at which the alloy will turn into a liquid. The difference between these two temperatures is called the crystallization interval.

If the soldering site is within this difference, then even small mechanical loads on the part can completely destroy the structure of the solder. Such a connection will exhibit high fragility and resistance.

Remember the main thing: you should not influence the connection in any way until the solder solder has completely crystallized.

Important properties of solders

Whatever the type and type of alloy, whatever material it is used with, it should not contain heavy metals or any other toxic substances above the established norm. The composition of the solder matches the material of the parts as closely as possible. Otherwise, you will not be able to get a reliable connection. There will be excessive fragility.

Any solder, regardless of type and purpose, must be heat-stable. Also, solder for soldering must be electrically stable. The coefficients of thermal expansion and thermal conductivity should be taken into account. They should not differ significantly from those values ​​that apply to soldered products.

Types of solders for soldering

All existing alloys for this operation are divided into soft, or fusible, where the melting point is up to 450 degrees Celsius, and hard. Here it significantly exceeds the above value.

Soft solders

Tin-lead alloys with different contents of components are considered one of the most popular and widespread. In order to give the material the necessary characteristics, various additional ingredients can be added to the solder composition. For example, bismuth and cadmium are used to lower the melting point. The addition of antimony increases the strength of the solder joint.

Lead and tin alloys have a low melting point and low strength. They should not be used for parts whose operation involves heavy load. These solders are also not recommended if the operating temperatures of the parts are above 100 °C. If you have to solder loaded parts with soft solders, you should try to increase the contact area of ​​the two products.

Among the most popular soft materials are POS-18, POS-30, POS-40, POS-61, POS-90. The numbers are shown here for a reason. This is the percentage of tin in the alloy. In industry, it is more often used in the production of electronics and instrument making. In everyday life, they can connect a variety of parts: circuits for televisions, microwaves, electric kettles and other small appliances.

Purpose of soft solders

POS-90 is designed to work with parts that will then be processed using galvanic technology. POS-61 can be used to repair high-precision equipment. The alloy is also ideal for joining high-demand parts made from a wide variety of materials. POS-61 has proven itself as a solder for soldering copper and brass. Solder is suitable when it is necessary to achieve strong connections with a high degree of electrical conductivity.

POS-40 is widely used for operations with non-critical and imprecise parts. In this case, the working area can heat up to high temperatures. POS-30 is suitable for soldering copper or brass, steel alloys and iron.

Solid

Among refractory alloys, only two groups are distinguished and widely used. These are mainly copper or silver alloys.

The first group includes solders made of copper and zinc. They are well suited for those connections that will only be subject to static loads. The fragility of these alloys does not allow their use in components that will experience shock or any vibration.

Copper solders or zinc-based compounds include PMC-36 and PMC-54. The first is an ideal solder for soldering brass and any other copper joints. The second is suitable for working on copper, bronze or steel parts.

If you need to connect two steel parts together, then you can use pure copper, brass grades L-62, L-62, L-68. These brass-based solders create stronger, more ductile joints. Copper alloys do not have these characteristics.

Silver alloys are considered the highest quality. The composition may also contain zinc and copper. PSR-70 – solder for soldering copper, for working with brass or silver parts. This element is suitable if the connection point must conduct electricity. PSR-65 is used in the production of jewelry, fittings, and water pipes. PSR-45 is necessary for connecting those parts that operate under vibration and shock loads.

Other types

There are also other, less popular solders. They are often used for rare metals or special conditions. For example, nickel-based compositions are intended for products that operate at elevated temperatures. They also solder stainless alloys. Gold-based solders are used to work with vacuum tubes. There are corresponding solders for magnesium.

Release form

Soldering materials and compounds come in a variety of forms. So, it can be wire, thin foil, tablets, powder. In addition, solder is available in the form of paste or granules. The shape determines how the solder will be delivered to the work area.

Features of aluminum soldering

Connecting aluminum parts by soldering is used in industry and in everyday life. For example, modern bicycle frames are made of aluminum alloys - they often break during extreme riding. The question arises: which solder should I choose?

It is believed that soldering aluminum is a very complex process. But in fact, this is true if the process uses materials for stainless steel or brass, steel, and copper. The reason for this is the oxide film. It is this that does not provide the required level of wettability, and the base metal does not dissolve.

How to solder aluminum and aluminum-based alloys

In order for the work to be carried out at the proper level, the solder for soldering aluminum must contain silicon, aluminum, as well as copper, zinc and silver. Today you can find formulations on sale where all these components are in different proportions.

When choosing reliable solder, it is important to consider the following. The maximum resistance to corrosion and high strength will have the connection that was made with solder, which contains a lot of zinc.

Also for aluminum you can use compounds based on tin and lead. But it is important to properly prepare the work surface, clean it with a stainless steel brush and use active fluxes. But experts do not recommend using such an element.

Any solder for soldering aluminum is high-temperature. The most optimal ones, which allow you to obtain a reliable connection, are aluminum-silicon and aluminum-copper-silicon.

How to solder copper?

As noted above, you can work with most compositions. Both low-temperature fusible and hard solders can be used. Compositions based on tin with lead, tin, silver, copper with silver and zinc are also used.

If you need to repair a computer motherboard or repair a TV in the country, any fusible elements will do. If you need to solder fittings on pipes or repair a plumbing system or refrigerator, then only hard solder for soldering copper will do. This is how you can get high-quality results.

Stainless steel

If you need to connect stainless steel parts, then professionals recommend using rods made of tin and lead. Materials containing cadmium also work well. Low-melting alloys based on zinc can be used. However, they should not be used together with carbon or low-alloy steels. The best solder for soldering stainless steel is a composition based on pure tin. In addition, only tin is allowed if the soldering area will be in contact with food.

If the work will be carried out in a dry or furnace atmosphere, then silver with manganese, chromium-nickel solders or pure copper (or even better, brass) should be used. When soldering has to be done in corrosive conditions, silver tinols with a small part of nickel are used.

Soldering steel

It is not difficult to connect two such parts together. An affordable and effective solder for soldering steel is POS-41. There is also POS-60 and others; even pure tin can be used. But zinc compounds are not suitable. Especially when it comes to carbon or low-alloy materials.

Soldering fluxes

During the operation, flux plays no less a role than solder. It is a chemical solvent and oxide absorber. It also protects metals from oxidation and increases wetting.

To work with elements based on lead and tin, hydrochloric acid and zinc chloride can be used as a flux. Borax and ammonium chloride are also suitable. These are active fluxes. Inactive substances include rosin, petroleum jelly, olive oil and many other substances.

For example, hydrochloric acid solutions can be used with soft solders. Zinc chloride is used with brass, copper, and steel. Ammonia sleeps perfectly dilutes and dissolves fatty substances. For aluminum, a composition of tung oil, rosin, and calcined zinc chloride is used. You can also use concentrated phosphoric acid.

So, we found out what solders exist, and which one is better to use in different cases.

Source: https://FB.ru/article/236397/pripoy-dlya-payki-medi-alyuminiya-latuni-stali-nerjaveyki-sostav-pripoya-dlya-payki-vidyi-pripoev-dlya-payki

Solders and fluxes for soldering with a soldering iron

Solders and soldering fluxes are indispensable when working with a soldering iron. In order for the solder to spread well over the surface of the parts being joined, a substance called flux is used. Depending on the metal of the parts and their size, strength and tightness of the connection, it is necessary to select a specific brand of these components. Let's take a closer look at the classification and learn how to select the necessary solder and flux for soldering.

Lead-tin solder is the main component when soldering with an electric soldering iron. It is produced in the form of a wire or tube of different diameters (the tubular one is filled with rosin inside).

As a rule, solder contains tin (an environmentally friendly metal) with the addition of lead (a cheaper component). The more lead there is, the darker the surface of the solder.

The markings use letters and numbers. For example, the designation POS-61 means: P – solder, O – tin, S – lead, 61 – % tin content. POS-61 is the most common type. It is indispensable for working with elements made of copper, brass and bronze with a sealed seam. Suitable for almost all occasions in everyday life and is not expensive.

Solders can be soft or hard. The melting point of soft ones is below 450˚С. Solid ones melt when heated above 450˚C and are not used for working with an electric soldering iron.

Technical characteristics and classification of soft solders:

Brand	Composition % of total mass	Melting point ˚С	Tensile strength	Application area
Wood's alloy	Tin - 12.5 Lead - 25 Bismuth - 50 Cadmium - 12.5	68,5	–	For parts sensitive to overheating, for the manufacture of fuses, toxic
Splavd Arce	Tin - 6.9 Lead - 45.1 Bismuth - 45.3	79	–	For parts sensitive to overheating, for the manufacture of fuses
POSV-50Splav Rose	Tin - 25 Lead - 25 Bismuth - 50	94	–	For parts sensitive to overheating
POSV-33	Tin - 33.4 Lead - 33.3 Bismuth - 33.3	130	–	For parts made of copper, brass, constantan with a sealed seam
POS-61 (tertiary)	Tin - 61 Lead - 39	190	4,3	For live parts made of copper, brass and bronze with a sealed seam
POS-61M	Tin - 61 Lead - 37 Copper - 2	192	4,5	For thin copper wires and printed conductors
POS-90	Tin - 90 Lead - 10	220	4,9	For dishes and medical instruments
POS-40	Tin - 40 Lead - 60	238	3,8	For contact surfaces in radio equipment and parts made of galvanized steel
POS-30	Tin - 30 Lead - 70	266	3,2	For parts made of copper, its alloys and steel
POS-10	Tin - 10 Lead - 90	299	3,2	For contact surfaces in radio equipment
Air - 1	Tin - 55 Zinc - 25 Cadmium - 20	200	–	For thin-walled parts made of aluminum and its alloys, toxic

Solder conducts current ten times less than copper or aluminum. For comparison:

• The electrical resistivity of tin-lead solder (conductivity) is 0.1-0.2 Ohm/meter.
• The conductivity of aluminum is 0.0271 Ohm/meter.
• Copper conductivity is 0.0175 Ohm/meter.

Flux brands

Flux is an auxiliary substance necessary to free the surfaces of soldered parts from oxides and promote better spreading of solder over the metal surface during soldering.

In the manufacture of the most common fluxes, rosin is used. It is obtained from coniferous wood (mainly pine). At a temperature of about 50°C, rosin softens, and at 250°C it begins to boil.

Rosin is not resistant to atmospheric moisture. It consists of 85-90% abietic acid. If you do not remove its remains after work, then oxidation of the soldering area occurs. This fact should not be ignored. Indeed, in addition, by absorbing water from the atmosphere, rosin increases its conductivity and can disrupt the operation of electronic devices, especially high-voltage circuits.

Soldering fluxes - composition and scope of application:

Name	Composition% of total volume	Application area	Cooking method	Removing residues
Rosin inactive fluxes
Light rosin	Light rosin – 100	Soldering of copper and its alloys with low-melting solders	Ready to use	Alcohol or acetone, brush
Alcohol-rosin	Rosin - 20 Alcohol - 80	Soldering of copper and its alloys with low-melting solders in hard-to-reach places	Dissolve rosin powder in ethyl alcohol
Glycerin-rosin	Rosin - 6 Glycerin - 14 Alcohol - 80	Sealed soldering of copper and its alloys with low-melting solders in hard-to-reach places	Dissolve rosin powder in ethyl alcohol, then add glycerin
Rosin active fluxes
Rosin zinc chloride	Rosin - 24 Zinc chloride - 1 Alcohol - 75	Soldering of non-ferrous and precious metals, critical parts made of ferrous metals	Dissolve mixed powders of rosin and zinc chloride in ethyl alcohol.	Acetone, brush
Rosin chloride-zinc (flux paste)	Rosin - 16 Zinc chloride - 4 Vaseline - 80	High-strength soldering of non-ferrous and precious metals, critical parts made of ferrous metals	Mix rosin and zinc chloride powders with technical petroleum jelly
Acidic active fluxes.
Zinc chloride	Zinc chloride - 25 Hydrochloric acid - 1 Water - 75	Soldering of parts made of ferrous and non-ferrous metals	The acid is slowly poured into the dish up to ¾ of its height with pieces of zinc, when the hydrogen bubbles stop emitting, the flux is ready	Washing with water or a solution of baking soda in water, with a brush
Rosin - 16 Zinc chloride - 4 Vaseline - 80	Flux paste. High-strength soldering of non-ferrous and precious metals, critical parts made of ferrous metals	Mix rosin and zinc chloride powders with technical petroleum jelly
Rosin - 24 Zinc chloride - 1 Alcohol - 75	Soldering of non-ferrous and precious metals, critical parts made of ferrous metals	Dissolve mixed powders of rosin and zinc chloride in ethyl alcohol.

Flux based on alcohol and solvents must be stored in an airtight container, otherwise the liquid will quickly evaporate.

Solder pastes

Solder paste (Tinol) is a mixture of solder and flux. This material cannot be replaced when soldering in hard-to-reach places and when installing unframed radio components. To do this, you need to apply the paste in the required amount to the soldering area and heat it with an electric soldering iron (full melting temperature 200°C). Flux residues after soldering are non-hygroscopic, non-conductive and non-corrosive.

You can make your own pasta. To do this, you need to choose a brand of solder and prepare sawdust using a file with a large notch. Then mix them with liquid flux to obtain a paste-like composition. The paste should be stored in an airtight container. The paste has a shelf life of no more than six months.

It is known that the main function of solder is good diffusion with the metal surface. In addition, it must have optimal temperature viscosity, allowing it to be evenly distributed over the surface of metals.

This factor of high-quality tinning is possible only in the absence of fatty deposits and oxides on the surfaces being soldered, the removal of which is carried out by fluxes.

Therefore, the final quality of the work will depend on what solders and fluxes you choose for soldering with a soldering iron.

Source: https://poweredhouse.ru/pripoi-i-flyusy-dlya-pajki-payalnikom/

All about POS solder

Greetings to dear readers! In this material I tried to collect all the data about PIC solder. This Tin-Lead Solder is the most popular solder for mounting radio components and is used more often than others in radio engineering. I will try to explain why this is so and tell you about the types and technical characteristics of POS series solders. I’ll also tell you a terrible secret about POS-60 and POS-62 solders. Go!

Types of POS solders

First, let's remember what types of solders are made from alloys of the tin-lead group. The most popular are antimony-free solders POS-10, POS-40, POS-61 and POS-90. POS solder containing antimony is called POSSU. Antimony in the solder adds several percent to its strength.

When we talk about melting a mixture of tin and lead, we need to remember the definitions of solidus and liquidus . When any mixture of two or more metals is heated, the melting (transformation from solid to liquid phase) of the lightest particles occurs first. This temperature mark is called the solidus of the alloy.

With a further increase in temperature, more refractory components begin to melt. As soon as they melt, the liquidus . The PIC solder is now completely melted. This process is explained in more detail by a picture taken from a presentation on the topic of alloys.

Between these two points is a state of increased ductility of the solder . In this state, the solder can be pulled and deformed without losing integrity.

There are eutectic alloys - solders, in which the solidus and liquidus points coincide. This is very convenient when soldering and indicates the high quality of the solder.

About the composition of solder

The name of the solder of the tin-lead group indicates the tin content in it. For example, POS-40 contains 40% tin, and POS-61 contains almost 61% tin. The rest consists of lead and additional impurities.

By appearance, you can estimate the composition of the solder by eye. If the PIC solder is more matte and dark, then it contains more lead. If it is lighter and shiny, then there is more tin. This is best understood by comparison.

Look at the photo to see what a sheet of tin and a sheet of lead look like.

The strength of solder depends not only on the alloy alloy, but also on the metal being soldered. For example, to solder copper or zinc, several percent of copper or zinc are added to the POS solder, respectively. This reduces chemical erosion of the metal and increases the surface strength of the joint.

Solder alloying

To improve performance characteristics, alloying of solder with the following substances is used:

• adhesion is improved by the addition of copper, cadmium, antimony, aluminum, silver and zinc;
• ductility and resistance to thermal cycling are improved by the addition of indium, silver, manganese, bismuth, and lithium;
• Nickel, cobalt, zinc, silicon, boron, iron add strength
• The corrosion resistance of solder is increased by nickel and copper;
• Heat resistance is increased by silicon, zirconium, tungsten, vanadium, cobalt, niobium, hafnium.

Technical characteristics of POS and POSSu solders

In order not to describe all the technical characteristics of solders of the tin-lead group, I will simply provide a table of parameters. It can be used to determine the melting point, density, electrical resistivity, thermal conductivity, tensile strength, elongation, impact strength and Brinell hardness of solders.

Analysis of the table shows that the most fusible among the list is cadmium solder POSK 50-18 with a melting point characteristic of 145 degrees Celsius. The strongest solder is POSSu 4-6 solder with a tensile strength of 6.5 kgf/sq.m. mm.

Technical characteristics of POS-10 solder

POS 10 solder has a distinctive chemical composition. It contains 9-10% tin, about 89% lead, 0.2% bismuth, 0.1% antimony and other impurities in small quantities. POS-10 solder is used for soldering and tinning contact surfaces of electronics. For example, they solder relays and fill control plugs in radio electronics housings.

The POS-10 soldering temperature is 299 degrees Celsius. The solidus point is 268 degrees.

Advantages of POS-10 solder:

• high melting point is useful when soldering equipment cases.

Disadvantages of POS-10 solder:

• low strength and tensile strength of about 3.2 kgf/sq.mm.;
• high resistivity - 0.2 Ohm x sq.mm./m;
• high content of lead, which is hazardous to health.

Technical characteristics of POS-30 solder

Solder for soldering of the POS 30 brand is an intermediate link between POS 10 and POS 40. The composition of POS 30 solder is as follows: 30% tin and 69.5% lead. The rest is impurities and doping.

Solder POS 30 can be easily replaced with POS 40, which is described below. The melting point (liquidus) is 238 degrees, and the plasticity temperature (solidus) is 183 degrees Celsius.

According to the technical characteristics, POS 30 solder is most often used for soldering and tinning of zinc sheets and radiators.

Advantages of POS-30 solder:

• good adhesion;
• high strength.

Disadvantages of POS 30 brand solder:

• high lead content;
• often produced in rods.

Technical characteristics of POS-40 solder

According to the chemical composition, POS 40 solder consists of 39-41% tin, 59% lead. The remaining impurities are in the same ratio as in POS-10. Soldering solder POS-40 is often used for soldering and tinning radio equipment casings made of galvanized iron with galvanized seams.

The soldering temperature of POS-40 solder is 238 degrees Celsius, and the solidus is 183 degrees.

Advantages of POS-40 solder:

• good ratio of ductility and melting point;
• because of this, it tolerates thermal cycling better than POS-61.

Disadvantages of POS-40 solder:

• high lead content, which is harmful to health;
• elevated liquidus temperature.

The terrible secret of POS-60 solder

Now the time has come for the terrible secret of POS 60 solder . According to GOST 21930-76 entitled “Tin-lead solders in ingots. Technical specifications" and GOST 21930-76 "Tin-lead solders in products. Technical specifications", solder such as POS-60 simply does not exist. download and view GOST 21930-76 itself . Here is the complete table from this GOST.

So “ POS-60 ” is jargon or a popular designation for “the solder that everyone solders with.” It seems to me that this is due to confusion in the designation of POS-61. Because when the tin content in the solder according to GOST is from 59 to 61%, it is more logical to call it POS-60 rather than POS-61.

Among the solders produced according to international standards there is Sn60Pb40 solder . This is a solder solder containing 60% tin and 40% lead. It could be called POS-60, if at least specifications for it were developed. According to international data describing the characteristics, the melting point of 60/40 solder is 191 degrees Celsius.

The same story with POS-62 type solder . Such lead solder according to GOST has not yet been invented. So, if they ask me “what is the melting temperature of POS-62 solder,” I know that the answer with the figure 184 degrees Celsius must be looked for in the imported solder catalog. For example, you can use the Kester solder catalog.

Technical characteristics of POS-61 solder

The designation of POS-61 brand solder, as we found out, is quite controversial, but you can’t argue against GOST. POS-61 is used for soldering and tinning of electronic components and printed circuit boards of precision instruments with highly hermetic seams, for which overheating is not allowed.

Composition of POS-61 solder

The chemical composition of POS-61 solder is as follows:

• Tin 59 - 61%;
• Antimony - no more than 0.1%;
• Copper - no more than 0.05%;
• Bismuth - no more than 0.02%;
• Arsenic - no more than 0.02%;
• Iron - no more than 0.02%;
• Nickel - no more than 0.02%;
• Sulfur - no more than 0.02%;
• Zinc - no more than 0.002%;
• Aluminum - no more than 0.002%;
• Lead - everything else - about 38.7 - 40.7%.

The soldering temperature of POS-61 solder is 220 degrees

Source: https://masterpaiki.ru/vse-pro-pripoy-pos.html

Physical properties and technical characteristics of solder for copper soldering

Traditionally, the most common method of joining copper pipes is soldering. To create a strong and durable seam, you need to choose the right copper solder and flux, carefully prepare the surface and follow the technology.

Which solder should I choose?

When soldering copper pipes, two main types are used:

• soft, with a melting point of up to 425°C;
• solid, with a temperature range of 460-560°C.

The use of silver-containing alloys is recommended as solders . They provide high quality connections, but are expensive. Copper-phosphorus compounds are more accessible and suitable for soldering less critical connections.

Copper-phosphorus

The melting point of copper-phosphorus solder is low. Copper solder allows you to do without flux compounds . The phosphorus contained in the composition will protect the work area from exposure to atmospheric oxygen.

The suture material, formed on the basis of copper-phosphorus solder, is very durable and resistant to vibration. Therefore, phosphorous compounds are widely used when soldering heat exchanger components.

Why do solders sometimes use copper solder when soldering steel parts, but copper cannot be soldered with steel solder? The reason is the difference in the melting temperatures of steel and copper. The copper blanks will already melt, but the steel will still heat up.

At the same time, copper-phosphorus solder is sensitive to overheating , so measures must be taken to cool the joint. The product is produced in the form of a rod. Copper soldering tape is also available . Copper-zinc low-temperature solders are also used for soldering.

Silver

Pure silver composition is not suitable for soldering copper products. They mainly use silver with the addition of iron, bismuth and other elements.

Silver-based copper solder has high wettability towards workpieces and penetrates perfectly into the narrowest gaps between them. The connections do not corrode and withstand large static and periodic dynamic loads.

Ag

The chemical composition of solders for soldering copper and silver workpieces is described in GOST 19738-74. They are designated by the letters PSR XX, where the numbers determine the percentage of silver

Practical use

Compositions with a high percentage of silver (50-72) have high electrical and thermal conductivity . They are used in electrical engineering and electronics.

Alloys with a medium percentage are cheaper and are used for soldering joints that are not subject to temperature stress.

Features of tinoles

A characteristic feature of silver-containing compounds is their low operating temperature. High fluidity allows the melt to penetrate into gaps and pores and create high-quality seams.

Brazing

Brazing alloys are used for joints of larger diameter tubes and pipelines. In this case, a paste-like flux, a gas burner for heating and the necessary auxiliary equipment and tools are used.

Low temperature

Low-temperature solders melt at temperatures up to 450°C . The low temperature avoids annealing of the base material of the pipe and preserves its physical and chemical properties. Solders are prepared on the basis of tin or zinc alloys. Lead is also used as a component.

High temperature

High-temperature solder for soldering copper is prepared on the basis of silver or copper, which has a high melting point. At temperatures above 450°C, the workpieces are annealed, leading to a decrease in their strength.

Physicochemical characteristics

Properties depend on the chemical composition of the alloy. Thus, low-temperature ones have less strength, but do not reduce the strength and elastic characteristics of the material of the parts.

High-temperature ones, on the contrary, create high-strength joints that can withstand static and dynamic loads. But when using them, great care is required so as not to burn or weaken the base material.

Specifications

temperature compositions lies in the range of 645-815 ° C. The seam can withstand tensile loads up to 250 MPa. The operating temperature of the compound, depending on the composition, is 150-250°C. In addition to copper itself, such solders allow you to join brass, red bronze, cast iron, steel and nickel. They also solder aluminum. In addition, they are used to connect copper and stainless steel parts.

Methods

There are two main methods of soldering copper blanks:

• High temperature . Silver or copper based refractory solder creates a rigid and durable connection. The seam is called solid and can withstand mechanical and temperature loads. To prevent annealing from leading to a deterioration in the strength of the main parts, the finished soldering should be cooled exclusively naturally, without blowing with cold air or immersing it in liquid.

• Low temperature . This type of soldering is called soft soldering. Solders are prepared on the basis of metals with low melting points. The low temperature avoids annealing and there is no reduction in the strength of the pipes. The method forms seams with a width of 7 to 50 mm, on pipes from 6 to 100 mm in diameter.

Soft connections cannot be used when installing gas pipelines.

What will be needed in the process?

For soldering you will need:

• flux for surface treatment of the workpiece;
• solder corresponding to the selected soldering method;
• device for chamfering the end of a pipe;
• wire brush and brush for cleaning workpieces;
• pipe expander;
• measuring instrument: tape measure, measuring gauge, square, spirit level;
• burner.

A portable propane torch makes it possible to heat a joint in a few seconds . In places where the use of an open flame is unacceptable, the joints are heated with an electric soldering iron with replaceable clamps and electrodes for different pipe diameters

Technology

After the accessories and tools are prepared, proceed to the soldering itself:

Cut the part to the required length

To cut pipe blanks, pipe cutters with manual or electric drive are used. To ensure an even cut, after each revolution the pressure-regulating flywheel should be tightened by a third of the stroke. The edge should be treated with a chamfer remover and cleaned with a brush. If the connection is butt, one of the pipes should be expanded. Next, the surfaces are degreased and the quality of their mating is checked.

Apply flux to the surface of the pipe

Flux paste is applied to the inner surface with a brush built into the lid of the jar. It should be completely covered with flux, but at the same time no excess should accumulate on it.

Connecting

The parts are inserted into each other with a slight twist in both directions . This helps distribute the flux evenly.

Excess flux must be wiped off with a clean rag.

When low-temperature soldering, the turned on torch is directed towards the joint . The joint must be heated evenly, smoothly moving the torch . The coil of solder is taken in the left hand. The wire touches the gap, the solder melts and fills it.

At this point, the flame is pulled slightly to the side, allowing the solder to flow into the gap.

The soldered joint must be cooled in the usual way, by blowing or wetting with liquid. This will avoid the annealing effect.

High temperature requires a hotter flame. It is obtained by burning a mixture of propane with oxygen or acetylene with air . The joint should be heated evenly and quickly, avoiding overburning. The required temperature of the workpiece (750°C) can be determined by the dark cherry color. The soldering compound, heated but not melted by the torch, is fed into the joint area.

Experienced craftsmen immediately heat the joint exactly enough to melt and flow the soldering compound. Beginning shareholders will have to practice on training blanks. Excess melt is removed with copper tape designed for removing solder. The soldered seam should cool naturally, without blowing cold air.

After cooling, use a clean, dry rag to remove any remaining flux paste.

Basic mistakes

Beginner shareholders often make mistakes. The most typical of them are:

1. Uncorrected surface defects after cutting: scoring, chips, out-of-roundness. Soldering over defects weakens the connection, reducing its durability and tightness.
2. Poor quality degreasing.
3. Narrowing of the installation gap. A narrow solder joint will also be unreliable.
4. Underheating of workpieces. Cold parts will not be able to melt the solder with their heat and ensure its flow into the mounting gap. Cold solder joints can fall apart with a simple touch.
5. Lack of flux paste. The part of the seam surface that is not covered with flux is not cleaned of the oxide film and is not soldered.
6. Burnt joint. In this case, the flux burns out, the oxide film is not completely destroyed, and scale appears on the surface. Solder strength is significantly reduced.
7. An attempt to test the strength of a hot joint. Leads to deformation of the solder layer in the mounting gap and its detachment from the parts.

Neglecting safety requirements is also a common mistake. High temperatures, harmful fumes, and chemically active fluxes require the use of personal protective equipment. These include:

• protective glasses;
• shoes, clothing and headwear made of non-flammable fabric;
• thick split leather gloves
• respirator.

There should be no flammable materials near the soldering area; it should be well ventilated. You cannot solder in the top position.

Correctly selected soldering composition allows you to obtain reliable and durable solder joints. It is equally important to use the appropriate flux and strictly adhere to the requirements of soldering technology and safety precautions.

It is better to solder the first few seams under the supervision of an experienced solder.

Source: https://svarka.guru/payka/oborudovaniya/pripoy-dlya-medi.html

Variety of solders for soldering

Soldering is one of the effective ways to connect various metal parts and device components. The advantages of soldering are that it creates a permanent connection, almost homogeneous in structure, moreover, it is electrically conductive and resistant to corrosion.

To join metals, a special substance is used - soldering solder. This is an alloy that is used to create a joint between parts.

Refractory and low-melting

Solders for soldering are divided into refractory and low-melting. They are also called hard and soft. All types of solders are widely used in mechanical engineering, electrical engineering, and electronics.

Hard solders are used when it is necessary to achieve high joint strength. Probably, such connections could be called constructive. Their melting point reaches 500 ℃ and above.

This temperature is dangerous for most components of electronic circuits, especially for semiconductor devices and limits their use, so other alloys are used for soldering - low-melting alloys.

They are obtained by adding more lead to tin. All low-melting solders have a melting point of about 200 - 240 ℃.

With a melting point less than 200 degrees

There are also solders with very low melting points. This is, for example, POSK-50-18. From the marking it follows that this solder contains 50% tin, 18% cadmium, and 32% lead.

This solder melts at a temperature of 142 – 145 ℃. It is very plastic, but due to its cadmium content, it is toxic.

Another example of such low-melting solders is POSV-50 (it has the name Rose). Here the number 50 indicates a bismuth content of 50%, and tin and lead are present in the composition in equal proportions - 25% each.

Solder melting temperature is 90 – 94 ℃. These two soldering products most often come in tablet-like shape and size. Wood's third alloy contains 10% tin, 40% lead, 40% bismuth, 10% cadmium.

Its melting point does not exceed 72°C. Due to the presence of cadmium in its composition, it is toxic. Rose and Wood alloys are quite expensive.

Indium solders are often used for soldering semiconductors, since their melting point is about 117 ℃. In this alloy, indium replaces tin, and lead is also added to soften it and make it more fluid.

Some indium solders can be used to solder glass. In this case, the edges of the latter are simply rubbed with paste before soldering.

Tin-lead

Depending on the composition of the alloys, more precisely, on the percentage of components, the names of solder brands are formed.

For example, POS-30. The letters abbreviate the chemical composition - tin-lead solder, and the number indicates the percentage of tin in the composition - 30%.

Alloys containing tin and lead are generally classified as low-melting solders for soldering.

The most common brands are:

• POS-90. Used when the presence of lead is undesirable. These can be various machines and mechanisms intended for the food industry and agricultural sectors. Lead, when combined with certain chemical elements and in the air, emits toxic fumes that are harmful to the health of living organisms.
• POS-60. Universal solder. It is widely used for soldering due to the combination of its good strength characteristics and the temperature to which radioelements are tolerant.
• POS-40. It is used for soldering galvanized iron products. Used in the repair of heating appliances and pipes.
• POS-30. This brand is used for tinning, that is, for applying a layer of tin to the surface in order to give it anti-corrosion properties.

Lead makes the alloy soft and fluid, making soldering easier. A rod with a high lead content (more than 30%) can be easily bent, whereas a pure tin rod can only be bent with great difficulty.

Containing antimony

To reduce the degree of oxidation of the alloy in the liquid state and give the soldering a better appearance, antimony is introduced into its composition. According to GOST 21930-76, all tin-lead solders for soldering, depending on the chemical composition, are classified into:

• antimony-free;
• low antimony, with antimony content up to 0.5%;
• antimonous, containing more than 0.5% antimony.

The same GOST also determines the areas of primary use of each brand.

Table 1. Chemical composition of solders

Chemical composition, % Brand of solder OKPO code Main components Tin Antimony Cadmium Copper Lead Antimony-free Low antimony Antimony

POS 90	17 2311 1100 04	89-91	—	—	—	The rest is the same
POS 63	17 2312 0100	62,5-63,5	—	—	—	«
POS 61	17 2312 1100 10	59-61	—	—	—	«
POS 40	17 2314 1100 00	39-41	—	—	—	«
POS30	17 2321 1100 09	29-31	—	—	—	«
POS 10	17 2326 1100 06	9-10	—	—	—	«
POS 61M	17 2312 1200 07	59-61	—	—	1,2-2,0	«
POSK 50-18	17 2313 1200 02	49-51	—	17-19	—	«
POSK 2-18	17 2343 1100 09	1,8-2,3	—	17,5-18,5	—	«
POSSu 61-0.5	17 2312 1400 01	59-61	—	—	—	The rest is the same
POSSu 50-0.5	17 2313 1100 05	49-51	—	—	—	«
POSSu 40-0.5	17 2314 1200 08	39-41	—	—	—	«
POSSu 35-0.5	17 2315 1200 03	34-36	0,05-0,5	—	—	«
POSSU 30-0.5	17 2321 1200 06	29-31	—	—	—	«
POSSu 25-0.5	17 2322 1200 01	24-26	—	—	—	«
POSSu 18-0.5	17 2323 1100 10	17-18	—	—	—	«
POS 95-5	17 2311 1200 01	Ost.	4,0-5,0	—	—	—
POSSu 40-2	17 2314 1300 05	39-41	1,5-2,0	—	—	The rest is the same
POSSu 35-2	17 2315 1300 00	34-36	1,5-2,0	—	—	«
OSSu 30-2	17 2321 1300 03	29-31	1,5-2,0	—	—	«
POSSu 25-2	17 2322 1300 09	24-26	1,5-2,0	—	—	«
POSSu 18-2	17 2323 1200 07	17-18	1,5-2,0	—	—	«
POSSu 15-2	17 2324 1100 05	14-15	1,5-2,0	—	—	«
POSSu 10-2	17 2326 1200 03	9-10	1,5-2,0	—	—	«
POSSu 8-3	17 2326 1300 00	7-8	2,0-3,0	—	—	«
POSSu 5-1	17 2327 1100 01	4-5	0,5-0,1	—	—	«
POSSU 4-6	17 2327 1200 09	3-4	5,0-6,0	—	—	«
POSSU 4-4	17 2327 1300 06	3-4	3,0-4,0	—	—	«

Foreign stamps

There are also foreign-made compounds. They are marked differently, but the mark can determine the composition of the alloy. An example is the Sb62Pb36Ag2 alloy produced by the American company Indium Corporation.

It contains 62% tin, 36% lead and 2% silver. Silver is often added to the composition to increase fluidity after the solder has melted.

Another example is the product produced by the Canadian company UNIVERSALPRIBOR. Its marking is SN62/36/2 NC. This material is in the form of a paste and from the marking it follows that its composition is: 62% tin, 36% lead, 2% silver. NC (No Clean) means that the solder balls are contained within a flux gel.

Pastes for microcircuits

Solder is also available in the form of solder paste. It is a plastic mass consisting of flux and a binder, which contains many tiny balls of tin-lead solder with flux.

Such pastes are used for stencil soldering, that is, when the use of conventional soldering methods is impossible due to the small size of the components.

These can be microcircuits or components in BGA packages. The pastes are applied to the terminals with a spatula and melted with a hairdryer or infrared soldering iron.

Due to the fact that solder pastes dry out quickly, they should be stored in special, hermetically sealed tubes.

To restore BGA packages, that is, to update the solder balls on their terminals, also called reballing, solder balls are produced. It can be either tin-lead or lead-free.

This is a high quality pure product with a very precise chemical composition.

The balls are stored in tightly closed jars at a temperature of +20 - +30 ℃ and a humidity of no more than 60-70%. The shelf life of such solder is usually no more than 12 months. Used for soldering critical components.

DIY making

If you have enough tin and lead, you can make your own solder. To maintain the proportions, you can weigh the required amounts of lead and tin on ordinary kitchen scales, be sure to use some kind of support.

Lead is poisonous, so there should be no traces of it on the scales. For the same reason, when working, it is necessary to organize good ventilation of the room, use safety glasses and gloves, and, if necessary, a respirator.

To weigh the required amount of materials, it is enough to know their density. For tin it is 7.30 g/cm³, for lead it is 11.35 g/cm³. By making a simple proportion, you can determine the amount for different compositions of alloys.

You can use a small steel container directly to prepare the alloy. In it you need to bring lead and tin to the melting temperature.

After they take on a liquid state, you need to remove the top layer with a steel spoon. This is slag formed when it combines with oxygen in the air.

Then you need to carefully but thoroughly mix the two metals and pour them into a mold made of some refractory material. Forms made of plaster or tin may be suitable for this.

This composition can be successfully used when installing electronic circuits, soldering wires and cables, and connecting copper or brass pipes.

All solders for soldering, despite their diversity, have different properties and characteristics. The correct selection of one or another composition for each specific case will ensure a high-quality and reliable connection using soldering.

Source: https://svaring.com/soldering/pripoj/klassifikacija

What solder to use for soldering microcircuits - Metalworker's Guide

Modern radio-electronic devices cannot be imagined without microcircuits - complex parts into which, in fact, dozens, or even hundreds of simple, elementary components are integrated.

Microchips make devices light and compact. You have to pay for this with the convenience and ease of installation and the rather high price of the parts. The price of a microcircuit does not play an important role in determining the overall price of the product in which it is used.

If such a part is damaged during installation, when replacing it with a new one, the cost may increase significantly. It is not difficult to solder a thick wire, a large resistor or a capacitor, all you need is basic soldering skills.

The microcircuit must be soldered in a completely different way.

To avoid annoying misunderstandings, when soldering microcircuits it is necessary to use certain tools and follow certain rules based on extensive experience and knowledge.

Soldering equipment

To solder microcircuits, you can use various soldering equipment, ranging from the simplest soldering iron to complex devices and soldering stations using infrared radiation.

A soldering iron for soldering microcircuits should be low-power, preferably designed for a supply voltage of 12 V. The tip of such a soldering iron should be sharply sharpened to a cone and well tinned.

To desolder microcircuits, a vacuum desoldering pump can be used - a tool that allows you to remove solder from the legs on the board one by one. This tool is similar to a syringe in which the piston is spring-loaded upward. Before starting work, it is pressed into the body and fixed, and when necessary, it is released by pressing a button and rises under the action of a spring, collecting solder from the contact.

A hot-air station is considered a more advanced equipment, which allows both dismantling of microcircuits and soldering with hot air. This station has in its arsenal a hairdryer with adjustable air flow temperature.

A piece of equipment such as a heat table is very popular when soldering microcircuits. It heats the board from below, while installation or dismantling is carried out from above. Optionally, the heating table can be equipped with top heating.

On an industrial scale, soldering of microcircuits is carried out by special machines using infrared radiation. In this case, the circuit is preheated, soldered directly, and the contacts of the legs are cooled step by step.

At home

Soldering microcircuits at home may be required to repair complex household appliances and computer motherboards.

As a rule, to solder the legs of the microcircuit, use a soldering iron or soldering gun.

Working with a soldering iron is carried out using regular solder or solder paste.

Recently, lead-free solder with a higher melting point has become increasingly used for soldering. This is necessary to reduce the harmful effects of lead on the body.

What equipment will be required?

To solder microcircuits, in addition to the soldering equipment itself, you will need some other equipment.

If the microcircuit is new and made in a BGA package, then the solder is already applied to the legs in the form of small balls. Hence the name - Ball Grid Array, which means an array of balls. These enclosures are designed for surface mounting. This means that the part is installed on the board, and each leg is soldered to the contact pads with a quick, precise action.

If the microcircuit has already been used in another device and is used as used spare parts, it is necessary to perform a reballing. Reballing is the process of restoring the solder balls on the legs. Sometimes it is also used in the case of a blade - loss of contact of the legs with the contact patches.

To carry out reballing, you will need a stencil - a plate of refractory material with holes located in accordance with the location of the microcircuit pins. There are ready-made universal stencils for several of the most common types of microcircuits.

Solder paste and flux

For proper soldering of microcircuits, certain conditions must be met. If the work is carried out with a soldering iron, then its tip should be well tinned.

For this, flux is used - a substance that dissolves the oxide film and protects the tip from oxidation before being coated with solder during soldering of the microcircuit.

The most common flux is pine rosin in a solid, crystalline form. But to solder a microcircuit, such a flux is not suitable. Its legs and contact spots are treated with liquid flux. You can make it yourself by dissolving rosin in alcohol or acid, or you can buy it ready-made.

In this case, it is more convenient to use solder in the form of filler wire. Sometimes it may contain powdered rosin flux inside. You can purchase a ready-made soldering kit for soldering microcircuits, which includes rosin, liquid flux with a brush, and several types of solder.

When reballing, solder paste is used, which is a base of viscous material that contains tiny balls of solder and flux. This paste is applied in a thin layer to the legs of the microcircuit from the back of the stencil. After this, the paste is heated with a hairdryer or infrared soldering iron until the solder and rosin melt. After hardening, they form balls on the legs of the microcircuit.

Work order

Before starting work, it is necessary to prepare all tools, materials and devices so that they are at hand.

When installing or dismantling, the board can be placed on a thermal table. If a soldering gun is used for dismantling, then to prevent its impact on other components, you need to isolate them. This can be done by installing plates made of refractory material, for example, strips cut from old circuit boards that have become unusable.

When using a desoldering pump for dismantling, the process is more accurate, but takes longer. The desoldering pump “charges” as it cleans each leg. As it fills with pieces of solidified solder, it needs to be cleaned.

There are several soldering rules that must be followed:

• Soldering the microcircuits on the board must be done quickly so as not to overheat the sensitive part;
• You can hold each leg with tweezers during soldering to provide additional heat removal from the body;
• When installing using a hair dryer or infrared soldering iron, you must monitor the temperature of the part so that it does not rise above 240-280 °C.

Electronic parts are very sensitive to static electricity. Therefore, when assembling, it is better to use an antistatic mat that is placed under the board.

Why dry chips?

Chips are microcircuits housed in BGA packages. The name, apparently, came from an abbreviation that meant “Numerical Integrated Processor”.

Based on experience, professionals have a strong opinion that during storage, transportation, and shipment, chips absorb moisture and during soldering, it increases in volume and destroys the part.

The effect of moisture on the chip can be seen if the latter is heated. Blisters and bubbles will form on its surface long before the temperature rises to a value sufficient to melt the solder. One can only imagine what is happening inside the part.

To avoid the undesirable consequences of moisture in the chip body, when installing boards, the chips are dried before soldering. This procedure helps remove moisture from the case.

Drying rules

Drying of chips must be carried out observing temperature conditions and duration. New chips that were purchased in a store, from a warehouse, or sent by mail are recommended to be dried for at least 24 hours at a temperature of 125 °C. For this you can use special drying ovens. You can dry the chip by placing it on a hot plate.

The drying temperature must be controlled to prevent overheating and failure of the part.

If the chips were dried and stored under normal room conditions before installation, it is enough to dry them for 8-10 hours.

Source: https://ssk2121.com/kakoy-pripoy-ispolzovat-dlya-payki-mikroshem/

Copper pipe soldering technology

Entire plumbing or heating systems made of copper are rarely made today, but they are still done. If you calculate the number of years during which copper can last, it turns out that it is not only inexpensive, but very cheap. However, the material itself is not the cheapest, but you can save on installation - soldering copper pipes is not the most difficult task in the world. There are certain rules and features, knowing which you can achieve a quality connection.

Types of copper pipes and their uses

There are two types of copper pipes on the market: annealed and non-annealed. After formation, annealed ones undergo additional heat treatment - they are heated to 600-700°C. This procedure returns elasticity to the material, which is lost during molding. Therefore, annealed pipes are more expensive, but also more flexible - they can even withstand freezing of water. The disadvantages of these products include lower strength - it decreases due to heating.

There are different types of copper pipes

Unannealed copper pipes are stronger, but practically do not bend. When installing plumbing or heating, they are cut into pieces, and all bends are made using appropriate fittings.

There are copper pipes with different wall thicknesses, sold annealed in coils of 25 and 50 meters, unannealed in runs of 3 meters. If we talk about the purity of the material, then according to GOST 859-2001, at least 99% copper must be present in products.

Connection methods

Most often, copper pipes are connected using soldering and a set of special shaped elements - fittings. There are also fittings for crimping. They have grooves with a rubber O-ring installed. They are crimped with special pliers. But this technology is used infrequently - soldering is considered more reliable.

Fittings for crimping

There are two technologies for soldering copper pipes using different solders:

• Low temperature - with soft solder. This is exactly our case. This type of connection is used when laying water pipes and heating systems with a working environment temperature of up to 110°C. Low temperature is a relative concept. In the soldering zone, materials are heated to 250-300°C.
• High temperature brazing. This type of connection is used in networks with high pressure and temperature of the transported medium. In household networks - rarely (although no one prohibits), more often in industrial ones.

What type of copper pipe soldering you use is your choice. Both types are suitable for both plumbing and heating. But high-temperature solder requires a professional torch, while soft solder can be melted even with a blowtorch or an inexpensive hand torch with a small disposable gas cylinder. To connect small-diameter copper pipes, no more is required.

Types of Copper Solder Fittings

In general, there are more than two dozen different shaped elements for copper pipes - fittings, but three types are most often used:

• couplings - for connecting two pipes;
• corners - for turning;
• tees - for creating branches in the pipeline.

Couplings for soldering copper pipes

The number of fittings used can be minimized - copper can be bent, which will reduce the number of angles needed. Also, if desired, you can do without couplings: one end of the pipes can be expanded (using an expander) so that the pipe goes into it and there is a gap for solder to get there (about 0.2 mm). When creating an expansion, the pipes must overlap by at least 5 mm, but more is better.

What’s hard to do without is tees. There is equipment for inserting a branch - a beading machine, but it is professional and costs a lot. So in this case it’s cheaper and easier to get by with tees.

There are fittings for soldering copper pipes with soldered solder

There are two types of fittings - conventional, with sockets, which provide the required clearance for solder to flow. Solder is supplied to the welding zone manually. There are fittings with built-in solder. Then a groove is formed on the socket, into which, during production, a piece of solder is installed, which makes the soldering process easier - you just need to heat the welding zone, but leads to an increase in the cost of fittings.

Consumables and tools

In addition to pipes and fittings, you will also need a torch, solder and flux for the soldering itself. And also a pipe bender and a few related little things to process before starting work.

Brush for cleaning fittings from the inside

Solder and flux

Soldering of copper pipes of any type occurs using flux and solder. Solder is an alloy usually based on tin with a certain melting point, but always lower than that of copper. It is fed into the soldering zone, heated to a liquid state and flows into the joint. After cooling, it provides a tight and durable connection.

For amateur soldering of copper pipes with your own hands, tin-based solders with the addition of silver, bismuth, antimony, and copper are suitable. Compositions with the addition of silver are considered the best, but they are the most expensive; the optimal ones are those with a copper additive. There are also ones with added lead, but they should not be used for plumbing. All these types of solder provide good seam quality and easy soldering.

Flux and solder - necessary consumables

Soft solder is sold in small spools, hard solder is sold in packs, cut into pieces.

Before soldering, the joint is treated with flux. Flux is a liquid or paste that allows molten solder to flow into a joint. There is nothing special to choose here: any flux for copper will do. Also, to apply the flux you will need a small brush. Better - with natural bristles.

To work with soft solder, you can buy a small hand torch with a disposable gas cylinder. These cylinders are attached to the handle and have a volume of 200 ml. Despite its miniature size, the flame temperature is 1100°C and higher, which is more than enough to melt soft solder.

What you should pay attention to is the presence of piezo ignition. This function is not superfluous - it will be easier to work with. There is a valve on the handle of the manual gas burner. It regulates the flame length (gas supply intensity). The same valve shuts off the gas if the burner needs to be extinguished. Safety is ensured by a non-return valve, which will shut off the gas supply if there is no flame.

Hand torch for soldering copper pipes

Some models have a flame deflector installed. It prevents the flame from dissipating, creating a higher temperature in the soldering area. Thanks to this, the burner with a reflector allows you to work in the most inconvenient places.

When working with household and semi-professional models, you must be careful not to overheat the unit so that the plastic does not melt. Therefore, it is not worth doing a lot of soldering at one time - it is better to let the equipment cool down and prepare the next connection at this time.

Related materials

To cut copper pipes, you need a pipe cutter or a hacksaw with a metal blade. The cut must be strictly vertical, which is ensured by a pipe cutter. And to ensure an even cut with a hacksaw, you can use a regular carpenter’s miter box.

When preparing pipes, they must be cleaned. There are special metal brushes and brushes for this (for cleaning the inner surface), but you can get by with sandpaper with medium and fine grain.

To remove burrs from cuts, there are chamfer removers. The pipe they used fits better into the fitting - its socket is only a fraction of a millimeter larger than the outer diameter. So the slightest deviations lead to difficulties. But, in principle, everything can be removed with sandpaper. It will just take more time.

It is also advisable to have safety glasses and gloves. Most home craftsmen neglect these safety measures, but burns are very unpleasant. These are all the materials and tools needed to solder copper pipes.

Step-by-step copper soldering technology

Soldering copper pipes begins with preparing the connection. The reliability of the connection depends on the quality of preparation, so devote enough time and effort to this process.

Soldering copper pipes consists of several stages

Preparing the connection

As has already been said, the cut of the pipe must be strictly vertical, without burrs, the pipe must not be wrinkled, the edge must be even and smooth. If there are even slight deviations, we take a bevel remover or sandpaper and bring the cut to perfection.

It is necessary to remove the oxidized layer

Next, take the fitting and insert the pipe into it. the part that goes into the socket requires cleaning. We take out the pipe and use sandpaper to remove the top oxidized layer from this part of the pipe. Then we carry out the same operation with the inner surface of the bell.

Flux application

Flux is applied to the entire cleaned surface - outside the pipe and inside the fitting. There are no difficulties here - the composition is evenly distributed with a brush.

The treated pipeline fragments are inserted into one another and fixed. If there is an assistant, he can hold the parts motionless. If not, you'll have to figure it out yourself. Next, the burner is ignited and the flame is directed to the connection point. The flame temperature is from a thousand degrees and above, and the joint must be heated to 250-300°C, and this takes 15-25 seconds. In this case, you can focus on the color of the flux - as soon as it darkens, it’s time to introduce solder.

Correct position of the torch when soldering copper pipes with your own hands

To ensure uniform heating, direct the burner flame in the middle of the joint. Then the entire welding zone heats up more evenly.

Soldering copper pipes with soft solder

Solder is injected into the joint - where the fitting and pipe connect. As it heats up, it begins to melt, spreads and fills the gap between the elements. You can only apply it to half the length - once it melts, it will flow into the rest of the joint. Actually, that's all - the soldering of the copper pipes is finished. All other connections are made the same way.

When using hard solder, everything is almost the same, only other burners are used - gas-flame ones, and during the soldering process you need to turn the pipe, winding the softened solder onto the pipe.

Source: https://otoplenie-doma54.ru/stroitelstvo/pajka-mednyh-trub-tehnologiya-oborudovanie-osobennosti.html