Quality of caprolon; what is the difference between caprolon A, B and C; caprolon properties

Since 2006, it has been producing cast polyamide (caprolon) and is currently one of the leading suppliers of engineering plastics in Russia. We offer a wide range of sizes of slabs, rods and bushings made of polyamide 6 block natural or dyed. Caprolon blanks are produced according to TU 2224-001-78534599-2006 and can be painted black, red and yellow without changing the properties of the material itself.

Caprolon (Polyamide 6 block, PA-6, PA-6) is a popular construction material that is obtained by anionic polymerization of caprolactam, which occurs directly in the injection mold in the presence of catalysts and activators.

The popularity of the material is due to its unique properties, which include:

excellent deformation-strength characteristics: polyamide 6 has high impact strength, combined with resistance to bending loads and rigidity; climate resistance: caprolon is resistant to temperature changes, moisture, sea water;
chemical inertness, resistance: PA 6 is immune to the action of weak acids, alkalis, ethers, ketones, alcohols and other hydrocarbons;
significant range of operating temperatures: constant operating temperature from -60 to 100°C, melting point - 220°C;
excellent dielectric properties;
high strength and wear resistance.

To improve the physical and mechanical characteristics, including antifriction properties, dispersed fillers (molybdenum disulfide, graphite) or a system of liquid oils are introduced into the polyamide matrix. This is how modified grades of caprolon are obtained: graphite-filled (MG), molybdenum-filled (MDM), oil-filled.

A little about the past of caprolon

The word “block” in the name “PA-6 block” is a term from the 60s of the last century, when caprolon was obtained only in the form of rectangular blocks . The blocks were cut into small pieces, and then the parts were sharpened. To produce small parts (for example, bushings), up to 90% of the block was thrown into chips .
And today, some enterprises store blocks from previous decades of production, fearing to send them into production, because... As a result of the primitive technology for producing caprolon, these blocks have internal stresses and tear when trying to cut them into blanks. The progressive method for the synthesis of caprolon blanks developed by NTO "Alvis" minimizes the occurrence of internal stresses in the material and makes it possible to obtain high-quality products.

Areas of application of caprolon (PA 6)

Thanks to the combination of the above properties, caprolon is widely used in almost all industries, including food and pharmaceutical. Caprolon's resistance to the action of hydrocarbons and petroleum products ensures its use in the oil production and oil refining industries, and resistance to gasoline and oils in auto, aircraft, and tractor construction.

The variety of products made from block polyamide 6 is due to its excellent anti-friction, dielectric properties, and high wear resistance. The material is used for the production of: bearings and other sliding parts; bypass and power pulleys, blocks and rollers of lifting mechanisms; housings, hubs, brackets and other parts operating under conditions of high shock loads; gear wheels, gears, chain sprockets, worm wheels and other elements of gear and chain transmissions; screws, separators, bushings, etc.

Physico-mechanical properties of caprolon

indicator name	meaning
density GOST 15139-69, g/cm3	1,145
tensile strength GOST 11262-80, MPa	80
relative elongation at break GOST 11262-80, %	>20
tensile modulus of elasticity DIN EN ISO 527, MPa	2800-3000
hardness Shore D GOST 24621-81	84
Impact strength according to Charpy GOST 4647-80, KJ/m2	without destruction
friction coefficient GOST 11629-75	0,39
water absorption to saturation in water ISO 62:1999, %	7
maximum temperature for short-term operation, C	+170
minimum temperature for short-term operation, C	-100
maximum constant operating operating temperature, C	+100
minimum constant operating operating temperature, C	-60
melting point, C	+220
fire rating UL 94, 3 mm	NV
specific volumetric electrical resistance GOST 6433.2-71, Ohm	1.00E+14
surface resistivity GOST 6433.2-71, Ohm*m	1.00E+13
coefficient of linear thermal expansion GOST 15173-70, 10-5	8
thermal conductivity GOST 23630.2-79, W/m C	0,26

comparative table of physical and mechanical properties of caprolon and its modified grades (MG, MDM, oil-filled) in PDF format.

Research

Caprolon grades “4-10” and “4-15” have a specific volume resistance of 70-90 MOhm•cm (at a voltage of 100 V), which ensures the drainage of static charge .
The material “caprolon-300” has electrically conductive properties. Glass-filled caprolon brand STP-20 produced by NTO "Alvis" has a thermal coefficient of linear expansion less than the special polymer polyetheretherketone with 30% fiberglass. For caprolon STP-20 - 0.000040, for polyetheretherketone with 30% fiberglass - 0.000075 (at +100°C).

NTO "Alvis" has created a new syntactic material - syntactic foam based on caprolon (grades SF-15, SF-25, etc.). The peculiarity of this material is its combination of high strength and low specific gravity.

NTO "Alvis" studied the water absorption of various grades of caprolon when in water for 4000 hours. For the M-40 brand, water absorption is 1.5-1.55% , for the Kaprolon-42 brand - 1.55-1.65%, for the base caprolon produced by NTO "Alvis" - 1.5-1.6% (according to reference books - 6-8%). These values can actually be considered equilibrium.

The physical and mechanical properties of caprolon produced by NTO Alvis are always slightly higher than the reference ones. Research conducted by Bryansk University has shown that the graphite-filled caprolon of the “Caprolon-42” brand we produce is superior in wear resistance to other domestic and foreign brands . It is not simply “tinted” with graphite (unlike the so-called “graphite-caprolone”). In “Caprolon-42”, graphite is evenly distributed throughout the workpiece, which ensures stable anti-friction, strength and electrical properties of the material.

Main advantages and properties of polyamide 6 block

Products made from caprolon are not inferior to their metal counterparts and even surpass them in a number of characteristics. While metal parts are susceptible to corrosion, have significant mass, and conduct electricity and heat well, polyamide products are distinguished by:

Low specific gravity with sufficient strength (polymers are 2–3 times lighter than aluminum and 5–8 times lighter than steel). This property is especially valuable when creating aircraft, shipbuilding, etc.
High corrosion resistance. Allows the use of products made from caprolon 6 block under conditions of environmental influence (moisture, sea water, for example, stern tube bearings), as well as exposure to aggressive environments (alcohols, ethers, dilute acids, solvents).
Vibration resistance. Polymers absorb vibrations 20 times better than aluminum and 100 times better than steel. Parts made from caprolon work well under high dynamic and shock loads.
Noise absorption and soundproofing. Another valuable property of polyamide 6 as a structural material. Parts made from it not only do not create additional noise, but also absorb it to some extent. For example, when replacing metal high-speed gears with plastic ones in gearboxes, noise is almost completely eliminated.
High dielectric properties. Polyamides, unlike most thermoplastics, have spark-extinguishing properties and resistance to galvanic corrosion, making them suitable for the manufacture of connectors, coils, switches and relays.
Cleanliness and ease of machining (milling, turning, drilling, grinding). Provides variety and complexity of manufactured parts, and also reduces time and other costs for their production. In addition, caprolon does not contain asbestos or other components hazardous to health released during mechanical processing.
Color variety. Changing the color of the material is possible by adding a color pigment during the production process, rather than by painting the finished product, as is the case with metal parts.
Low friction coefficient values. Provides the ability to use caprolon parts in the operation of friction pairs without additional lubrication, significantly reducing wear and labor intensity of maintenance.
Environmental friendliness. Under normal operating conditions, the material is safe for humans and the environment.
Long service life. Even under constant mechanical load, parts made of block polyamide 6 last many times longer than metal.
Low cost. The difference in the cost of polymer materials and metals is about 50%.

GOSTs and specifications for caprolon

On the Internet, people often search for “caprolon GOST 7850”. Caprolon is not produced according to GOST standards! Since Soviet times, norms and rules for the production of PA-6 (polycaproamide, polyamide-6) have been established by technical requirements (TU). And according to GOST 7850 (or rather, GOST 7850-2013), caprolactam (cyclic lactam (amide) of ε-aminocaproic acid) is produced. Caprolactam is a colorless crystalline powder or liquid composition; it is from caprolactam that caprolone is produced.

You can buy caprolon manufactured according to: TU 2224-001-78534599-2006, technical specifications TU 2224-036-00203803-2012, TU 2224-003-39046337-04, TU BY 690686201.001-2010 and others.

Caprolon sheets

Sheet caprolon – polyamide PA-6 in the form of a plate with a rectangular cross-section. Widely used in industry for the production of bearings, shafts, rollers, liners, bushings and other equipment elements. The sheets vary in thickness, weight, and dimensions. You can buy sheet caprolon with a thickness from 6 to 250 millimeters, sheet size 1000*1000 mm, 1000*2000 mm, 500*700 mm, and other sizes. The weight of the sheet depends on its dimensions and thickness, for example, the weight of one sheet of polyamide 6, 10 mm thick, 1000*1000 mm in size is about 11.7 kg, and 40 mm thick with the same size is about 49.3 kg.

You should not strike sheet caprolon with a hammer or other objects, because the surface is slippery and smooth, elastic. You should only handle the sheets with gloves; the sharp edges can damage your skin. Mechanical processing is carried out on standard metalworking machines with tools made of carbon steel or, during long-term work, with special tips made of tungsten carbide or diamond-coated. When producing complex parts, it is advisable to distribute the scope of work into several simple operations in order to avoid damage and cracking of the semi-finished product.

When storing sheet caprolon in the cold (cold rooms) before putting it into production, it is necessary to keep the sheets for about 5 - 7 days at a higher temperature (warm rooms).

Caprolon or fluoroplastic

The technical characteristics of fluoroplastic and caprolon are very similar. These two materials are harmless to humans, therefore they are often used in medicine and the food industry. The chemical resistance of both plastics is also excellent.

Application

Due to the unique properties and technical characteristics of PA-6 polyamide, many different types of products are made from it for a wide variety of industries and human activities. These are rollers, pulleys, liners, caprolon bushings, elements of sliding and rolling bearings.

The ability to absorb dynamic loads, noise and vibration makes this type of plastic in demand for covering guides, wheels, blocks, as well as in the manufacture of gears (for example, in a household electrical appliance such as an electric meat grinder).

PA-6 is also used for the manufacture of parts for lifting mechanisms, high-pressure gearboxes, friction units subject to high loads, etc. It is used to produce impellers, pump blades, gears, rollers for conveyor belts, and housings. At food industry enterprises you can often find cutting boards made of PA-6.

Why do we recommend purchasing caprolon from us?

produces and offers for sale:

caprolon rod with a diameter of 50 to 500 mm, length 500, 1000, 3000 m;
caprolon sheet thickness from 6 to 120 mm, dimensions 1000x1000 mm, 1000x2000 mm;
pipes (bushings) made of caprolon with an external diameter from 50 to 1000 mm and a custom internal diameter.

It is possible to buy caprolon wholesale and retail from our warehouses in Moscow, Klin, Moscow region and Dzerzhinsk, Nizhny Novgorod region.

In addition, it has special equipment and carries out mechanical processing and cutting (cutting) of polymer plastics according to agreed upon schemes (drawings).

We will be happy to provide you with more detailed information by calling toll-free tel: 8-800-505-59-55 or email [email protected] Our specialists will answer all your questions, help with the choice of material, organize delivery in Moscow and other cities of Russia.