Electric welding for beginners: how to learn to weld?
If you want to learn how to use electric welding, you should first acquire the necessary equipment, since electric welding for beginners is a responsible undertaking. For use at home, even an entry-level welding machine is sufficient. Although, absolutely anyone will do:
- rectifier;
- inverter;
- welding transformer.
It is good if the maximum current exceeds 160 amperes. You should also acquire protective equipment:
- welder mask;
- work gloves;
- clothing made of dense material (not synthetic);
- boots made of rough leather or tarpaulin;
- hammer;
- metal brush.
The only basic safety equipment you need is a fire extinguisher or at least a bucket of water. You must also take all precautions when using electrical appliances.
What do you need to know?
To learn how to use electric welding, you should remember one simple rule: electrodes must be selected taking into account the thickness of the metal, and the current strength of the device must be set according to the type of electrode.
When working on a welding transformer, a current of 30-40 amperes is set for each millimeter of metal thickness. When using an inverter, the maximum current for a 3 mm thick electrode is 80 amperes, since at 100 amperes it can cut metal. In the case of electrodes of 2 mm thickness, the current is set to 20-30 amperes, and when set to 40 amperes it can cut metal.
Start of welding work
Before you start welding, you need to prepare a workplace, as well as workpieces that will be used for training in welding. Using a metal brush or grinder, clean the welding point from rust and dirt. To fix and join the elements to be welded, you need to use clamps or a vice.
Learning how to operate a welding machine starts with something simple – welding beads. To do this, you need to buy electrodes with a diameter of 3 mm. For beginners, ANO-21 or ANO-36, which are considered universal and the most inexpensive, will be enough. It is better to use new electrodes, as old ones sometimes become damp and become unusable.
The ground clamp must be attached to the part, and the electrode must be inserted into the holder.
Arc ignition methods
- You need to strike the electrode on the metal part, like a match, slowing down slightly. When an arc occurs, it must be held by holding the electrode a few millimeters from the surface of the workpiece and moving it to the side.
- Tapping is the second method. You need to tap the end of the electrode on the workpiece and immediately tear it off while holding the arc.
You need to move the electrode along the workpiece, maintaining a gap of 3 to 5 mm.
You can learn how to weld with a welding machine by first learning how to move the electrode correctly over the workpiece. The inclination should be about 75 degrees in the direction of the arc. By setting the correct current value, the arc will be stable, and the metal and electrode will simultaneously melt.
If the current is too high, the metal will start to burn and spatter.
Let's try to cook
Try welding two parts together. Light the arc and begin to move the electrode smoothly along the seam at an angle of 75 degrees. In this case, you should carry out oscillatory movements with a crescent, as if raking the metal from each workpiece to the welded joint. This way you will end up with an even and continuous seam. After the metal has cooled, you need to beat off the slag with a hammer.
The main thing is to practice, and then your skill will begin to improve. In the future, you will be able to master more complex welding techniques, for example, welding vertical or ceiling seams. You will always find application for such abilities in the household.
Source: http://sdelais.ru/elektrosvarka-dlya-nachinayushhix-kak-nauchitsya-varit.html
How to convert amps to watts and vice versa?
> Knowledge base >
14.06.2018
On household appliances (mixer, hair dryer, blender), manufacturers write the power consumption in watts, on devices that require large amounts of electrical load (electric stove, vacuum cleaner, water heater) - in kilowatts. And on sockets or circuit breakers through which devices are connected to the network, it is customary to indicate the current strength in amperes. To understand whether the outlet will support the device you are connecting, you need to know how to convert amps to watts.
Power units
Converting watts to amperes and vice versa is a relative concept, because these are different units of measurement. Amps are a physical quantity of electric current, that is, the speed at which electricity flows through a cable. Watt is the amount of electrical power, or the rate of electricity consumption. But such a translation is necessary in order to calculate whether the value of the current corresponds to the value of its power.
Converting amperes to watts and kilowatts
Knowing how to calculate the correspondence between amperes and watts is necessary in order to determine which device can withstand the power of connected consumers. Such devices include protective equipment or switching equipment.
Before choosing which circuit breaker or residual current device (RCD) to install, you need to calculate the power consumption of all connected devices (iron, lamps, washing machine, computer, etc.). Or, on the contrary, knowing the cost of a circuit breaker or protective shutdown device, determine which equipment will withstand the load and which will not.
To convert amperes to kilowatts and vice versa, there is a formula: I=P/U, where I are amperes, P are watts, U are volts. Volts are the mains voltage. In residential premises, a single-phase network is used - 220 V. In production, to connect industrial equipment, a three-phase electrical network is used, the value of which is 380 V. Based on this formula, knowing the amperes, you can calculate the correspondence to watts and vice versa - convert watts to amperes.
Situation: There is a circuit breaker. Technical parameters: rated current 25 A, 1-pole. You need to calculate what wattage of devices the machine can withstand.
The easiest way is to enter technical data into a calculator and calculate the power. You can also use the formula I=P/U, it will turn out: 25 A=x W/220 V.
x W=5500 W.
To convert watts to kilowatts, you need to know the following measures of power in watts:
- 1000 W = 1 kW,
- 1000 000 W = 1000 kW = MW,
- 1000,000,000 W = 1,000 MW = 1,000,000 kW, etc.
This means 5500 W = 5.5 kW. Answer: a machine with a rated current of 25 A can withstand the load of all devices with a total power of 5.5 kW, no more.
Apply a formula with voltage and current data in order to select the type of cable based on power and current. The table shows the current correspondence to the wire cross-section:
Copper cores of wires and cables Core cross-section, mm²Copper cores of wires, cablesVoltage 220 V | Voltage 380 V | |||
Current, A | power, kWt | Current, A | power, kWt | |
1,5 | 19 | 4,1 | 16 | 10,5 |
2,5 | 27 | 5,9 | 25 | 16,5 |
4 | 38 | 8,3 | 30 | 19,8 |
6 | 46 | 10,1 | 40 | 26,4 |
10 | 70 | 15,4 | 50 | 33 |
16 | 85 | 18,7 | 75 | 49,5 |
25 | 115 | 25,3 | 90 | 59,4 |
35 | 135 | 29,7 | 115 | 75,9 |
50 | 175 | 38,5 | 145 | 95,7 |
70 | 215 | 47,3 | 180 | 118,8 |
95 | 260 | 57,2 | 220 | 145,2 |
120 | 300 | 66 | 260 | 171,6 |
How to convert watt to ampere
You need to convert watts to amperes in a situation where you need to install a protective device and you need to choose what rated current it should have. It is clear from the operating instructions how many watts a household appliance connected to a single-phase network consumes.
The task is to calculate how many amperes in watts or what kind of socket to connect to if the microwave oven consumes 1.5 kW. For ease of calculation, it is better to convert kilowatts into watts: 1.5 kW = 1500 W. We substitute the values into the formula and get: 1500 W / 220 V = 6.81 A. We round the values up and get 1500 W in terms of amperes - microwave current consumption is at least 7 A.
Source: https://odinelectric.ru/knowledgebase/kak-perevesti-ampery-v-vatty-i-obratno
How many amperes are in a 220V outlet?
To find out how many amperes are in a regular 220V home socket, first of all, remember that current is measured in Amperes :
Current strength “ I ” is a physical quantity that is equal to the ratio of the charge “q” passing through the conductor to the time (t) during which it flowed.
The main thing that is important to us in this definition is that current strength occurs only when electricity passes through a conductor, and while nothing is connected to the outlet and the electrical circuit is broken, there is no movement of electrons, and accordingly there are no amperes in such an outlet either.
In an outlet to which there is no load connected, there are no amperes, the current strength is zero.
Now consider the case when some electrical appliance is connected to the outlet and we can calculate the amount of current
If our electrical wiring were not protected by the automation installed in the electrical panel, and the maximum connected power of the equipment (as well as the current strength) were not controlled by anything, then the number of amperes in a 220V household outlet could be anything . The current would increase until the high temperature destroyed the socket mechanism or wires.
When high current flows, conductors or connections not designed for it begin to heat up and break down. As an example, we can take the spiral of an ordinary incandescent lamp, which, when an electric current passes, becomes hot, but because The tungsten from which it is made is a refractory metal; it does not collapse, which cannot be expected from the contacts of the socket mechanism.
To calculate how many amperes will be in the outlet when connecting a particular device or equipment, if you do not have an ammeter at hand, you can use the following formula:
Formula for calculating the current in a socket
I=P/(U*cos f) , where I - Current (ampere), P - power of connected equipment (W), U - network voltage (Volts), cos f - power factor (if this indicator is not in the characteristics equipment, take 0.95)
Calculation example:
Let's calculate using this formula how many amperes the current is in a regular home socket with a voltage (U) of 220V when connecting an iron with a power of 2000 W (2 kW) to it, the cos f of the iron is close to 1.
I=2000/(220*1)=9.1 Ampere
This means that when the iron with a power of 2 kW is turned on and heated, the current in the outlet will be about 9.1 Amperes.
When several devices are simultaneously plugged into one outlet, the current in it will be equal to the sum of the currents of this equipment.
What is the maximum amperage for sockets?
Most often, modern 220V home sockets are designed for a maximum current of 10 or 16 Amperes . Some manufacturers claim that their sockets can withstand 25 Amps , but there are very few such models.
Old, Soviet sockets, which are still found in our apartments, are generally designed for only 6 Amperes.
The maximum that you can find in a standard typical apartment is a power outlet for an electric stove or hob, which can withstand current up to 32 Amperes.
These are manufacturer-guaranteed indicators of the current strength that the socket will withstand and not be destroyed. These characteristics are necessarily indicated either on the socket body or on its mechanism.
When choosing electrical installation products, keep in mind that, for example, a 16 Ampere outlet will withstand about 3.5 kilowatts of power, and a 10 Ampere outlet will only handle 2.2 Kilowatts.
Below is a table of the maximum power of connected equipment for outlets, depending on the number of amperes for which they are designed.
TABLE OF MAXIMUM EQUIPMENT POWER FOR 6, 10, 16, 32 Amp Outlets
Most often, all household electrical equipment that is plugged into standard 220V sockets does not exceed 3.5 kW in power; more powerful devices have different connectors for connection or are supplied without an electrical plug, designed to be connected to terminals or to electrical plugs for power sockets .
I advise you to always choose sockets designed for a current of 16 Amps or more - they are more reliable. After all, most often electrical wiring in apartments is laid with copper cable with a core cross-section of 2.5 mm2. and place the machine on 16 Ampere sockets. Therefore, if you choose an outlet rated for 10 Amperes and connect a large load to it, the automatic protection will not work, and the outlet will begin to heat up and melt, which may cause a fire.
If you still have questions about the characteristics of sockets or their choice, be sure to write, I will try to help. In addition, any criticism, additions, opinions are welcome - write.
Source: https://RozetkaOnline.ru/poleznie-stati-o-rozetkah-i-vikluchateliah/item/171-skolko-amper-v-rozetke-220v
1 watt is how many amperes
We choose two things in the store that should be used “in tandem”, for example, an iron and a socket, and suddenly we are faced with a problem - the “electrical parameters” on the label are indicated in different units.
How to choose instruments and devices that suit each other? How to convert amps to watts?
Related but different
It must be said right away that a direct conversion of units cannot be done, since they represent different quantities.
Watt - indicates power, i.e. the rate at which energy is consumed.
Ampere is a unit of force that indicates the speed at which current flows through a specific section.
To ensure trouble-free operation of electrical systems, you can calculate the ratio of amperes and watts at a certain voltage in the electrical network. The latter is measured in volts and can be:
- fixed;
- permanent;
- variables.
Taking this into account, a comparison of indicators is made.
"Fixed" translation
Knowing, in addition to the values of power and strength, also the voltage indicator, you can convert amperes to watts using the following formula:
P=I*U
In this case, P is the power in watts, I is the current in amperes, U is the voltage in volts.
In order to constantly be “in the know,” you can create an “ampere-watt” table for yourself with the most frequently encountered parameters (1A, 6A, 9A, etc.).
Such a “relationship graph” will be reliable for networks with fixed and constant voltage.
"Variable Nuances"
For calculations at alternating voltage, another value is included in the formula - power factor (PF). Now it looks like this:
P=I*U*KM
An accessible tool such as the online amperes to watts calculator will help make the process of converting units of measurement faster and easier. Don’t forget that if you need to enter a fractional number in a column, do so through a period, and not through a comma.
Thus, to the question “1 watt - how many amperes?”, using a calculator you can answer - 0.0045. But it will only be valid for a standard voltage of 220V.
Using the calculators and tables available on the Internet, you can not agonize over formulas, but can easily compare different units of measurement.
This will help you select circuit breakers for different loads and not worry about your household appliances and the condition of the electrical wiring.
Ampere - watt table:
6 | 12 | 24 | 48 | 64 | 110 | 220 | 380 | Volt | |
5 Watt | 0,83 | 0,42 | 0,21 | 0,10 | 0,08 | 0,05 | 0,02 | 0,01 | Ampere |
6 Watt | 1 | 0,5 | 0,25 | 0,13 | 0,09 | 0,05 | 0,03 | 0,02 | Ampere |
7 Watt | 1,17 | 0,58 | 0,29 | 0,15 | 0,11 | 0,06 | 0,03 | 0,02 | Ampere |
8 Watt | 1,33 | 0,67 | 0,33 | 0,17 | 0,13 | 0,07 | 0,04 | 0,02 | Ampere |
9 Watt | 1,5 | 0,75 | 0,38 | 0,19 | 0,14 | 0,08 | 0,04 | 0,02 | Ampere |
10 Watt | 1,67 | 0,83 | 0,42 | 0,21 | 0,16 | 0,09 | 0,05 | 0,03 | Ampere |
20 Watt | 3,33 | 1,67 | 0,83 | 0,42 | 0,31 | 0,18 | 0,09 | 0,05 | Ampere |
30 Watt | 5,00 | 2,5 | 1,25 | 0,63 | 0,47 | 0,27 | 0,14 | 0,03 | Ampere |
40 Watt | 6,67 | 3,33 | 1,67 | 0,83 | 0,63 | 0,36 | 0,13 | 0,11 | Ampere |
50 Watt | 8,33 | 4,17 | 2,03 | 1,04 | 0,78 | 0,45 | 0,23 | 0,13 | Ampere |
60 Watt | 10,00 | 5 | 2,50 | 1,25 | 0,94 | 0,55 | 0,27 | 0,16 | Ampere |
70 Watt | 11,67 | 5,83 | 2,92 | 1,46 | 1,09 | 0,64 | 0,32 | 0,18 | Ampere |
80 Watt | 13,33 | 6,67 | 3,33 | 1,67 | 1,25 | 0,73 | 0,36 | 0,21 | Ampere |
90 Watt | 15,00 | 7,50 | 3,75 | 1,88 | 1,41 | 0,82 | 0,41 | 0,24 | Ampere |
100 Watt | 16,67 | 3,33 | 4,17 | 2,08 | 1,56 | ,091 | 0,45 | 0,26 | Ampere |
200 Watt | 33,33 | 16,67 | 8,33 | 4,17 | 3,13 | 1,32 | 0,91 | 0,53 | Ampere |
300 Watt | 50,00 | 25,00 | 12,50 | 6,25 | 4,69 | 2,73 | 1,36 | 0,79 | Ampere |
400 Watt | 66,67 | 33,33 | 16,7 | 8,33 | 6,25 | 3,64 | 1,82 | 1,05 | Ampere |
500 Watt | 83,33 | 41,67 | 20,83 | 10,4 | 7,81 | 4,55 | 2,27 | 1,32 | Ampere |
600 Watt | 100,00 | 50,00 | 25,00 | 12,50 | 9,38 | 5,45 | 2,73 | 1,58 | Ampere |
700 Watt | 116,67 | 58,33 | 29,17 | 14,58 | 10,94 | 6,36 | 3,18 | 1,84 | Ampere |
800 Watt | 133,33 | 66,67 | 33,33 | 16,67 | 12,50 | 7,27 | 3,64 | 2,11 | Ampere |
900 Watt | 150,00 | 75,00 | 37,50 | 13,75 | 14,06 | 8,18 | 4,09 | 2,37 | Ampere |
1000 Watt | 166,67 | 83,33 | 41,67 | 20,33 | 15,63 | 9,09 | 4,55 | 2,63 | Ampere |
1100 Watt | 183,33 | 91,67 | 45,83 | 22,92 | 17,19 | 10,00 | 5,00 | 2,89 | Ampere |
1200 Watt | 200 | 100,00 | 50,00 | 25,00 | 78,75 | 10,91 | 5,45 | 3,16 | Ampere |
1300 Watt | 216,67 | 108,33 | 54,2 | 27,08 | 20,31 | 11,82 | 5,91 | 3,42 | Ampere |
1400 Watt | 233 | 116,67 | 58,33 | 29,17 | 21,88 | 12,73 | 6,36 | 3,68 | Ampere |
1500 Watt | 250,00 | 125,00 | 62,50 | 31,25 | 23,44 | 13,64 | 6,82 | 3,95 | Ampere |
And another video on the topic:
Source: https://www.0rv.ru/2017-08-23/1-vatt-skolko-amper
Electrodes for inverter welding
You can quickly and efficiently weld any, even the most complex metal structures, using inverters. These units have quickly become part of modern operational processes because they are easy to operate and produce high-quality welds that are smooth and neat. Of course, the main component of the welding process is the electrodes for welding with an inverter. Essentially, it is a metal rod that is coated with a special material called coating.
Welding electrodes are made from different steel wires that comply with GOST 2246-70. Therefore, electrodes for inverter welding are divided into several groups according to the raw material.
- Made from alloy wire. For example, from Sv-08Kh3G2SM.
- Highly alloyed - Sv-30Х15Н35В3Б3Т.
- Made of carbon - Sv-10G2.
The brands of welding wire are listed one at a time, but their list is quite wide.
As for the protective coating (coating), it is specially applied to the rod in order to protect the weld pool from exposure to oxygen on the molten metal. It is this chemical element that negatively affects the quality of the material, creating oxide films on its surface. This is feather. The second is arc stabilization.
The protective coating is applied to the welding rod by pressing, so the bond between the two materials is very high. The coating itself is divided into four types.
- Main.
- Rutile.
- Sour.
- Cellulose.
The first and last types are used only when welding with direct current. The rest are both with direct current and alternating current.
Which electrodes are best for cooking with an inverter?
Electrodes for the inverter are divided into two groups.
- Conventional ones, which are used everywhere for any designs. These include the ANO and MR brands.
- Consumables for critical structures. These include the SSSI brand.
All welders believe that the SSSI brand is very capricious. Not everyone can cook with these electrodes; experience and qualifications are required. Therefore, it is better for beginners to carry out welding with an inverter using conventional methods.
Electrode brands
To answer the question of how to choose electrodes, you need to understand the brands indicated above.
SSSI
Their main purpose is welding products made of carbon and low-alloy steels. As mentioned above, they are used to assemble structures that are subject to increased requirements. Particularly stringent requirements for welds, which must have increased impact strength and ductility.
Welding can be done at low temperatures. The coating is basic, the current is constant, the polarity is reversed. Rod diameter: 2-5 mm. The welding seam is of high quality, high density. Structures welded with these electrodes cope well with temperature changes, bending loads and shocks.
MR
There are two positions in this category.
- MP-3. They are used to connect carbon blanks, the joint of which can withstand a resistance (temporary) of up to 490 MPa. The coating is rutile, the current is alternating or direct, the polarity is any. You can cook with an electrode in any position with a reservation. So, in the lower position, welding is carried out with electrodes with a diameter of up to 6 mm, in a vertical position up to 5 mm, in the ceiling (upper) position up to 4 mm. Using MP-3, you can cook contaminated or rusty-coated workpieces. With them, welding is carried out with increased productivity.
- MR-3S. This is a model that is used for the same purposes as the previous one. The joint welded by it can withstand resistance up to 450 MPa. Coating – rutile-cellulose, current – alternating and direct, polarity – any. Welding position – any. They can even cook wet metals.
The brand of MR consumables for beginners can be called the best electrodes. They are not capricious, they can easily tolerate the process itself, a small splash of metal, plus an excellent seam.
ANO
We must pay tribute to this brand, which all experts consider universal. ANO is the most popular brand today. If we were to choose from all the types offered by manufacturers, then this is the one.
Using these electrodes (welding for inverter), you can weld workpieces up to 5 mm thick in different positions, even vertically from top to bottom. In this case, the joining of two metals can be: butting, overlapping, angular. There are no great requirements for the cleanliness of the welded edges; welding of oxidized surfaces can be carried out. They also perform root welding of thick workpieces. The coating is rutile-cellulose. Current – alternating or direct. Polarity – any.
In the model range of this type there is the ANO-4 brand with rutile-carbonate coating, which is used for welding critical structures.
OK 63.34
If it becomes necessary to weld two stainless steel workpieces, this can be done using an inverter, using an electrode from the Swedish manufacturer ESAB. By the way, this electrode can be used to connect structural steel products.
The seam from such a consumable is equal to the smooth transition from the base metal. In this case, slag is formed in small quantities and is easy to remove. You can weld any position of joints in metals with a thickness of 6-8 mm in root welding. Although the electrode itself was designed for welding thin stainless steel products. You can use it to connect butt and overlap joints. It is also used for multilayer welding not only in the horizontal plane, but also in the vertical.
Carbon and graphite electrodes
Metals are rarely welded with an arc using graphite and carbon electrodes. This type of welding is performed in shielding gases with filler wire or direct action. In this case, the electrode itself does not melt; the metal that is being welded melts. Carbon electrode welding is carried out with direct current with straight polarity.
An important component of the welding process is the tight pressing of the edges of the workpieces to each other. This can be done with tack welding, spot welding or mechanical devices (clamps, clamps, etc.). By the way, this technology can only be used in the down position.
Welding process
The work of a welder depends not only on the correctly selected brand of electrodes. You will have to select the correct diameter and accurately set the welding parameters on the inverter itself. This mainly concerns the current strength. In addition, it will be important to know which output (plus or minus) to connect the consumable you have chosen.
The diameter of the welding rod must be equal to the thickness of the workpiece to be welded. For example, the thickness of the parts being welded is 3 mm. This means that it is better to cook them with an electrode with a diameter of 3 mm. If you are welding thick metal, for example, 10 mm, then you can use any of the diameters, because welding in this case will be carried out layer by layer. But even here it is better to use a thick consumable.
As for the polarity, it depends on which output the electrode is connected to: negative or positive. If to the minus, and the plus is respectively connected to the workpiece being welded, then this is direct polarity. If it's the other way around, then it's the opposite.
What are the differences between the two types of connection? Everyone knows that the flow of electrons (which is also an electric current) moves from minus to plus. And the element of the welding process that is connected to the positive heats up more. That is, if you change the location of the electrode relative to the connection position, you can change the intensity of its heating.
Attention! With an electrode with a diameter of 3 mm, it is better to weld metal 2 mm thick with reverse polarity. And using the same consumables, it is better to cook metal 6 mm thick with direct polarity.
Now, as for the current strength when welding with an inverter. It is usually indicated on the packaging. But you can use a simple ratio: 20-30 amperes of current per millimeter of rod diameter. Let's face it, the range is quite wide.
But it will be necessary to take into account the mode of laying the weld. That is, it will be laid continuously without separation, or with separation. In the first case, the calculation takes an indicator of 20 amperes, in the second - 30.
Although all these are just recommendations, because you need to take into account a fairly wide list of welding mode criteria.
- Fluidity of the base metal, its grade.
- The speed of the welder's hand.
- Electrode position during welding. For example, in the ceiling position the current is reduced.
The optimal regime will come with time and experience. Therefore, the welder must pay attention to the weld pool. It is precisely this indicator of the quality of the selected mode. The correct seam should be uniform.
If a lot of metal has formed in the bathtub, it means that either the arc is too short or the welding speed was insufficient. If a saddle turned out in the bathroom, then the seam was welded too quickly, or the arc was too long.
The displacement of the metal in the bathroom to one side indicates that the electrode's even, strictly axial movement was not maintained. In addition, the current strength was large.
Choosing a good option that matches the mode and metal is not always easy. A beginner cannot do this, so manufacturers give recommendations on the packaging. More or less they coincide with the actual ones. But, as mentioned above, everything will come with experience. We suggest you watch the video - which electrodes are best to choose for welding with an inverter.
Source: https://svarkalegko.com/materials/vybor-elektrodov-dlya-invertora.html
Nuances of using MP3 electrodes and their technical characteristics
Experienced welders usually do not have any difficulties when they have to choose the most suitable electrodes for installing low-alloy steels. Most often, specialists give preference to MP-3 welding electrodes, and it is no coincidence. This consumable material is characterized by high operational efficiency and quality of workmanship, which is determined by the requirements of current GOSTs and the specific use of welded products in various industries.
Welding elements of the MP-3 brand are suitable for joining workpieces made of carbon and low-carbon steels. They can be welded in close contact or leave a small gap. In the latter case, experts recommend choosing the welding mode very carefully and using less than the rated current to avoid the formation of defects or cracks in the metal.
Additive materials produced under this brand are advantageous in that during their use a minimal amount of substances is released, so there is no doubt about their safety. They are indispensable for welding carried out in particularly difficult conditions, since they are the least demanding on the cleanliness of the surface, which may have rust stains or moisture, but this does not greatly affect the quality of welding.
Welding work is carried out using conventional transformers that maintain a minimum voltage of 50 V. MP-3 welding material can also be used for mounting parts of medium or large thickness.
The metal can be easily welded throughout the entire recess, ensuring high strength of the joint created.
Based on the technological conditions of welding work, when working with these electrodes, it is not necessary to create a large arc to obtain a temperature sufficient to set the metal with the electrode .
As part of the preparatory stage, the electrodes must be dried and calcined, which only has a positive effect on their working properties. Electrodes of this brand can be used in combination with transformers that support operation with direct and alternating current. Filler material can be worked in any position due to the fact that, regardless of the operating conditions, they can provide a high quality connection.
At the end of welding, it is necessary to perform the final operation - remove slag from the metal. This is done very easily, so the quality of the connection remains consistently high. The coating of the electrode directly affects its inherent advantages.
The welding material has a special chemical composition, thanks to which it is possible to maintain a stable arc when working in any plane.
Due to the stability of the arc, the quality of welding is consistently high, regardless of the influence of extraneous factors.
Rutile coated electrodes
Rutile coating is titanium dioxide in powder form, used to increase the strength characteristics of the weld and stabilize the combustion process.
Although electrodes with a rutile coating are noticeably more expensive, they have a number of advantages that provide them with undeniable advantages over other types of electrodes.
Rutile is most effective at connecting elements containing moisture and rust, helping to reduce metal splashes, thereby reducing its consumption. A distinctive feature of the electrodes is the ease of slag separation.
MR-3
A fairly well-known and popular type of rutile electrodes are MP-3 elements. They are used primarily for connecting critical structures made of carbon steels with a carbon content of at least 0.25% and low-alloy steels. When working with MP-3 electrodes, a continuous arc is formed, which guarantees a neat, durable and even seam. These electrodes can operate at any current.
During welding, MP-3 electrodes can be held in any position except vertical. This is due to the fact that a high-quality connection can only be created with incorrect polarity. MP-3 allows you to perform welding work even on an oxidizing surface and using an extended arc.
The high demand for welding materials of this brand is due to the presence of a lot of positive properties, among which we should highlight the ability to provide a high-quality connection even in the presence of traces of rust, moisture and dirt on the surface, as well as high productivity of welding work.
MP-3 welding elements are manufactured taking into account the requirements defined by GOSTs 9466 and 9467. The latter states that they are of type E46 and are used primarily for joining low-alloy steels with a mechanical tensile strength of up to 50 kgf∙m/cm2 and carbon steels. The metal to be welded must have a thickness of at least 3 mm and no more than 20 mm.
For the production of filler material, a special wire of type SV-08 with a cross-section of 3 to 6 mm is used. Based on the thickness of the base, electrodes can be divided into several groups depending on their diameter. Electrodes of the MP-3 brand differ from other types of elements by the presence of a rutile coating, the chemical composition of which is associated with the performance characteristics of the welding material.
The length of the elements can range from 300 to 450 mm. Additionally, they may vary in weight:
- 3 mm - 32 g;
- 4 mm - 62 g;
- 5 mm - 93 g.
One package may contain different amounts of welding material depending on their diameter:
• 3 mm – 84 pcs.;
• 4 mm – 42 pcs.;
• 5 mm – 44 pcs.
Manufacturers of MP-3 welding elements point out the importance of observing their storage conditions. The selected place should be heated and dry, the air temperature should not fall below + 15 degrees. Electrodes must be protected from excessive moisture, contamination and mechanical stress. If there are signs of moisture, the welding elements must be calcined for 1 hour at a temperature of + 180 degrees Celsius before use.
Application
Welding elements of the MP-3 brand are intended for welding work at constant or variable current, guaranteeing a voltage in no-load mode of at least 50 V. In the case of supply from a direct current power source, the polarity must be reversed. During the welding process, the filler material can be held in any plane.
Technological features
- High connection quality and performance;
- Hassle-free re-ignition;
- It is easy to separate the slag crust from the weld seam;
- Minor amount of metal spatter;
- Simplicity of the process of creating a weld;
- There are no difficulties in igniting the electric arc and maintaining its stable combustion.
Under normal temperature conditions, the weld metal, as well as the deposited metal, acquire the following strength characteristics:
- The mechanical tensile strength indicator is no more than 46 kgf/mm2;
- Relative elongation - 18%;
- Impact strength - 8 kgf∙m/cm2.
To correctly calculate the operating current, it is necessary to take into account the features of using electrodes and their diameter:
- with a diameter of 6 mm only in the lower location - 300-360 A;
- 5 mm for vertical 160−200 A, for lower -180−260 A;
- 4 mm for vertical 140-180 A, for bottom 160-220 A, for ceiling 140-180 A;
- 3 mm for vertical 90-110 A, for bottom 100-140 A, for ceiling 100-120 A.
Depending on the weight, about 1.7 kg of MP-3 is consumed per 1 kg of metal for welding.
The filler material of this brand can be used to connect structures both long and using short tacks. With their help, it is possible to perform metal connections without preliminary preparation, which may have:
- wet surface;
- traces of oxides and contaminants;
- signs of rust.
Welding elements MP-3 are also suitable for connecting elements along gaps, but when using a minimum current. Otherwise, pores may appear in the seam. The presence of the letter “m” (MR-3m) in the marking of welding elements indicates the presence of a rutile-ilmenite coating, and the letter “c” (MR-3s) indicates the use by the manufacturer of a rutile coating containing special ionizing additives.
If we compare these two types of electrodes in terms of characteristics, then these are the same MP-3 electrodes.
Welding material MP-3 simplifies the arc ignition process due to the presence of special additives in the coating when using low-power welding machines with a voltage of about 50 V.
In addition, they are more preferable than conventional MP-3 electrodes due to higher sanitary and hygienic indicators . Welding carried out using such elements is accompanied by the release of no more than 0.6 g of manganese.
When using conventional MP-3 electrodes, 1.25 g of the substance is released.
In addition, MP-3 elements allow for more uniform seams, which has a positive effect on the mechanical characteristics of the joint.
Design and material of manufacture
For the production of MP-3 electrodes, wire of different sections can be used. The manufacturing technology requires applying a special rutile coating to each product. The filler material may differ in length, which can be 300–450 mm, and in outer diameter, its value varies in the range of 2–6 mm.
This design allows the use of welding material MP-3 for welding work on unprepared surfaces that have dirt and traces of rust. During storage, it is necessary to maintain optimal humidity in the room. For rutile coating, it should not exceed 1.5%, otherwise, before use, the electrodes must be calcined for at least 60 minutes at a temperature of +180 degrees.
During welding, it is necessary to focus on the nominal characteristics that a high-quality weld . Subject to the requirements of the working process technology, the connection must have a tensile strength of 46 kgf/mm². The limit of weld deposition coefficient is 8.5 g/A*h. To determine the required number of electrodes, the mass of the deposit during welding must be taken into account. For MP-3 electrodes this parameter is 1.7 kg/hour.
To obtain reliable welded joints, it is necessary not only to have welding skills, but also to use suitable consumables. Among the electrodes that have proven themselves well, it is especially worth highlighting the electrodes of the MP-3 brand. They have a lot of useful properties, among which it is especially worth noting that they are undemanding to the quality of the surfaces of the metals being welded.
This filler material can be used for welding joints of parts containing moisture, dirt and oxides on the surface. Moreover, the end result does not suffer from this in any way.
These electrodes also have other positive properties that are well known to experienced welders.
However, it must be taken into account that MP-3 electrodes are a highly specialized filler material that is suitable for welding only low-alloy and carbon steels with a carbon content of 0.25%.
Therefore, it is necessary to know the features of the use of these welding elements in order to comply with all the requirements of the welding process. This is especially true for the magnitude of the operating current, on which the quality of the weld largely depends.
Source: https://tokar.guru/svarka/elektrody/tehnicheskie-harakteristiki-mr3-elektrodov.html
Convert how many amperes a kW has online. Calculator for converting current amperes to power watts
Power in an electrical circuit represents the energy consumed by a load from a source per unit time, indicating the rate at which it is consumed. The unit of measurement is Watt [W or W].
The current strength displays the amount of energy passed over a period of time, that is, it indicates the speed of passage. It is measured in amperes [A or Am].
And the voltage of electric current flow (potential difference between two points) is measured in volts. Current strength is directly proportional to voltage.
To independently calculate the Ampere / Watt or W / A ratio, you need to use the well-known Ohm's law. Power is numerically equal to the product of the current flowing through the load and the voltage applied to it. Determined by one of three equalities: P = I * U = R * I² = U²/R.
Therefore, to determine the power of the energy source when the current in the network is known, you need to use the formula: W (watts) = A (amps) x I (volts). And to make the reverse conversion, you need to convert the power in watts to the current consumption in amperes: Watt / Volt. When we are dealing with a 3-phase network, we will also have to take into account the coefficient of 1.73 for the current strength in each phase.
How many Watts are in 1 Ampere and amperes in a cotton wool?
To convert Watts to Amps at alternating or direct voltage you will need the formula:
I = P/U, where
I is the current strength in amperes; P – power in watts; U – voltage in volts, if the network is three-phase , then I = P/(√3xU), since it is necessary to take into account the voltage in each of the phases.
The root of three is approximately equal to 1.73.
That is, in one watt there is 4.5 mAm (1A = 1000 mAm) at a voltage of 220 volts and 0.083 Am at 12 volts .
When it is necessary to convert current into power (find out how many watts are in 1 ampere), then use the formula:
P = I * U or P = √3 * I * U, if calculations are carried out in a 3-phase 380 V network.
This means that if we are dealing with a 12-volt automotive network, then 1 ampere is 12 Watts, and in a 220 V household electrical network, this current strength will be in an electrical appliance with a power of 220 W (0.22 kW). In industrial equipment powered by 380 Volts, as much as 657 Watts.
Ampere – Watt conversion table:
Source: https://etlib.ru/calc/amps-watts-conversion