Taps and dies. Product purpose, features and choice
Tools > FITTING
There are a huge number of connections: welded, rivet, glued, keyed, splined and others. Some of them are one-piece; you can’t take them back apart. The parts are tightly attached to each other. In some cases this is a plus. But sometimes you need the ability to disassemble and reassemble elements without damaging them. Here it already makes sense to use detachable connections.
The most popular of them is threaded. Such connections are formed by bolts, screws, studs and other similar fasteners. The advantage is that the connection can withstand high loads, is suitable for high-performance processes, and has a low price. In addition, you can create carvings with your own hands. It is enough to buy suitable taps and dies , which can easily be used to prepare external or internal threaded connections of various types and calibrations.
What are these devices? How to choose them correctly for a workshop or garage?
A little about devices
The die is a nut with axial holes that form cutting edges. There are also recesses on the surface to remove the resulting chips. Usually the working part looks like an internal cone with 8-10 turns. The design can be solid, sliding or split. The last two options are considered universal, since you can change the diameter of the thread being created.
Alloy steel of different grades is used as the manufacturing material. High-speed metal and various hard alloys are also suitable. Such materials ensure high strength of the dies and their durability.
Taps are designed for internal threads. The tool looks like a regular fastener with grooves, like a screw or bolt. But the purpose of using taps is different: one end of them is attached to the machine, and the workpiece is put on the other side. As the tool rotates, threads begin to appear. The advantage is that taps can be used both manually and on a machine. So the device is used in various areas, including everyday life.
Choosing the right tools
Taps and dies may be sold separately. Buying tools individually is convenient for those who lack a certain product or do not need a set. If you have a workshop, it is better to take a set. Good kits are sold in various stores, including Lainer .
So, you select a set. To make the right decision, follow these simple tips:
- Determine exactly what tools you need. There are two accepted thread standards: metric and inch. The first one is used more often. The cutting edges of the metric die are characterized by the presence of conical blades. This tool is more common, so it's better to use it.
- Look carefully at the threads of the die. It is important that the last turns of the blades have a triangle-shaped profile. With such dies it is easier to make a thread into which a nut can be inserted without any problems.
- Taps and dies can be used manually or on special machines. Please note that the machine process is much faster.
- It is better to prefer solid dies to sliding ones. Although the latter can change the diameter of the thread, better processing is ensured by solid products.
Otherwise, the choice of dies and taps is simple. Especially for a specialist. If you are buying a set not for yourself, but as a gift, it is better to consult with a consultant.
262. What is soldering? Soldering is the process of creating a permanent joint between metals using an additive bonding material called solder, with the solder being brought to a liquid state during the soldering process. Melting temperature
SURFACE ROUGHNESS AND MANUFACTURING TOLERANCES
4. What is surface roughness? The surfaces of all parts after machining are not perfectly smooth, since the cutting edges of the tool leave marks on the surface in the form of certain irregularities and ridges
Source: https://msd.com.ua/slesarnoe-delo/metchiki-i-plashki-prednaznachenie-izdelij-osobennosti-i-vybor/
Application of metals and their alloys
The fact that the properties of metals change when they are fused became known back in ancient times. 5 thousand years ago, our ancestors learned to make bronze - a mixture of tin and copper. Bronze is harder than both metals in its composition.
The properties of pure metals, as a rule, do not meet the necessary requirements, therefore, in almost all spheres of human activity, not pure metals, but their alloys are used. This is a material that is formed as a result of the solidification of the melt of two or more separate substances. In addition to metals, their composition may also include non-metals, for example, carbon or silicon.
By adding admixtures of other metals and non-metals in a certain amount, you can obtain many thousands of materials with a wide variety of properties, including those that none of the elements that make up the mixture have.
Compared to the original metal, the alloy can be mechanically stronger and harder, with a significantly higher or lower melting point, more resistant to corrosion, more resistant to high temperatures, practically not change its dimensions when heated or cooled, etc.
Use as structural materials
The alloys used to make various structures must be strong and easy to process. In construction and mechanical engineering, mixtures of iron and aluminum are most widely used. Iron alloys such as steel are characterized by high strength and hardness. They can be forged, pressed, welded.
Cast iron is used to make massive and very durable parts. For example, central heating radiators and sewer pipes used to be cast from cast iron; boilers, railings and bridge supports are still made today. Cast iron products are made using casting.
Aluminum alloys used in structures, along with strength, must be lightweight. Duralumin and silumin are aluminum compounds; they are indispensable in aircraft, carriage and shipbuilding. Some aircraft components use magnesium mixtures, which are very light and heat-resistant.
In rocket science, lightweight and heat-resistant compounds based on titanium are used. To improve impact resistance, corrosion resistance, and wear resistance, alloys are alloyed - special additives are introduced. The addition of manganese makes the steel impact resistant. To obtain stainless steel, chromium is added to the mixture.
Tool alloys
Designed for the manufacture of cutting tools, dies and parts of precision mechanisms. Such connections must be wear-resistant and durable, and their strength should not decrease significantly when heated. Such requirements are met, for example, by stainless steels that have undergone special processing (hardening).
Adding substances to alloys that improve their properties is called alloying. To impart the necessary properties, tool steels are usually alloyed with tungsten, vanadium or chromium.
Application in the electrical industry, electronics and instrumentation
Alloys serve as an indispensable material in the manufacture of particularly sensitive and high-precision instruments, various kinds of sensors and energy converters. For example, a mixture of nickel is used to make transformer cores and relay parts. Individual parts of electric motors are made from cobalt compounds. An alloy of nickel and chromium - nichrome, which has high resistance - is used to make heating elements for stoves and household electrical appliances.
Of the copper compounds in the electrical industry and instrument making, the most widely used are brass and bronze. Brass is indispensable in the manufacture of devices, parts of which are shut-off valves. Such devices are used in gas and water supply networks. Bronze is used to make springs and spring contacts.
Application of low-melting alloys
The main required property is a specified low melting point. This property is, in particular, used for soldering microcircuits. In addition, these compounds must have a certain density, tensile strength, chemical inertness, and thermal conductivity.
Low-melting mixtures are made from bismuth, lead, cadmium, tin and other metals. Such alloys are used in temperature sensors, thermometers, fire alarms, for example, Wood's alloy.
And also in foundry for the production of lost wax models, for fixation of bones and prosthetics in medicine. The sodium-potassium compound (melting point –12.5 °C) is used as a coolant for cooling nuclear reactors.
Low-melting mixtures are used in foundry and are indispensable in fire alarm sensors
Application in jewelry
The use of pure precious metals in jewelry is not always justified and advisable due to their high cost, physical and chemical characteristics. To make gold jewelry more hard and wear-resistant, alloys with other metals are used. The best additives are silver (lowers the melting point) and copper (increases hardness). Pure gold is used very rarely, as it is too soft and easily deformed and scratched.
Nozzles for laboratory instruments are made from a mixture of gold with 10–30% other noble metals (platinum or palladium), and jewelry and electrical contacts are made from compounds with 25–30% silver.
Alloys in art
Tin bronze (a mixture of copper and tin) is one of the first metal compounds mastered by man. Compared to pure copper, it has greater hardness, strength and is more fusible. Bronze is successfully used to produce castings with complex configurations, including art casting. The classic brand of bronze is bell bronze.
One of the new trends in art is the production of artistic cast iron products. Cast iron products are significantly superior in quality to forged products. Cast iron is a much more brittle metal and not as malleable as steel.
But even from such a seemingly rough material, real works of foundry art can be obtained by casting, for example, cast stairs or window bars.
Such products are subject to only surface corrosion and do not require careful maintenance.
Information taken from the site: yaklass.ru
Source: https://m-splav.ru/primenenie-metallov-i-ih-splavov/
