Caprolon

Caprolon — buy cast polyamide-6 at Pipeline Systems of Ukraine

Caprolon is a cast polyamide-6 engineering plastic, poured as a block and then turned, milled or cut. Bushings, pads, rollers, guides, gears and washers for sliding joints are machined from the stock. It is lighter than bronze, runs with little lubrication or on water and does not spark.

The polymer resists oils, hydrocarbons, alcohols and weak alkalis. Concentrated mineral acids, phenols, formic and acetic acid attack it — use PTFE there. Caprolon absorbs moisture: dimensions drift, which matters on close fits and in open air. The working temperature band depends on the grade and the maker’s specification and must not be copied from one datasheet onto the whole group.

Typical forms are rods, sheets, slabs and ready bushings; oil-filled and graphited grades exist for heavier sliding duty. When selecting, specify diameter or thickness, stock length and whether a stress-relief anneal is needed before finish machining. Exact figures depend on the maker, size and design and must be checked against the datasheet of the specific product.

You can order caprolon from the Pipeline Systems of Ukraine online store.

Caprolon is a structural PA6 polyamide supplied in rods and sheets in accordance with Technical Specifications TU 20.16.54-001-39823025-2019. It is used as a substitute for bronze, brass and laminated phenolic material in friction assemblies, including plain bearings, bushings, gears, rollers, support components and gaskets.

The product range includes rods from 20 to 250 mm in diameter and 1 m in length, as well as sheets from 5 to 50 mm thick in a standard size of 1000 × 2000 mm. The material is available in its natural milky-white colour or in a graphite-modified black version with improved antifriction properties.

Available Forms

Applications

Sliding assemblies. Bushings, bearings and slide blocks used instead of BrAZh bronze. Caprolon reduces component weight by a factor of 6–7, requires no lubrication and does not damage the mating shaft under dry-friction conditions.

Gear drives. Gears and sprockets for low-speed drives. The material operates quietly and absorbs impact loads.

Rollers and wheels. Conveyor and lifting equipment, trolleys and roller conveyors.

Gaskets and seals. Used in mechanically loaded assemblies where soft TMKSh rubber or compressed fibre gasket material is unsuitable.

Housing and support components. Inserts for metal structures, impact-absorbing components and protective liners.

Technical Properties

• Operating temperature: −40 to +100°C, with short-term exposure up to +120°C.

• Density: 1.15–1.16 g/cm³ — approximately seven times lighter than bronze and 1.5 times lighter than aluminium.

• Tensile strength: 70–90 MPa; compressive strength: up to 100 MPa.

• Coefficient of friction against steel: 0.2–0.3 without lubrication and 0.04–0.08 with oil.

• Water absorption over 24 hours: up to 1.5%. Moisture absorption affects the dimensions of finished components and must be considered when specifying precision fits.

• Dielectric strength: breakdown voltage of 30–40 kV/mm.

• The material is not intended for contact with food products or drinking water. Food-grade polypropylene or PTFE F-4 should be used for these applications.

Frequently Asked Questions

What is the difference between Caprolon and PA6 polyamide?

Caprolon is PA6 polyamide produced by the anionic, or casting, polymerisation of caprolactam. Casting technology makes it possible to manufacture larger blocks and blanks with a more uniform structure than extruded polyamide. The industrial names Caprolon V, cast polyamide 6 and PA6G refer to the same material.

Should I choose a sheet or a rod?

The choice depends on the shape of the finished component. For rotational components such as bushings, gears and rollers, choose a rod with a diameter 10–20 mm greater than the finished part. This reduces the machining allowance and the amount of material removed as swarf.

For flat components such as gaskets, guides and liners, choose a sheet of the appropriate thickness. Cutting flat components from a rod is uneconomical, while machining a bushing from a sheet is not practical.

Can Caprolon be used in wet environments?

Yes, provided that water absorption is taken into account. During the first 24 hours of contact with water, Caprolon absorbs up to 1.5% moisture, which increases the component dimensions by approximately 0.3–0.7%. Fits for bearings and bushings used in submerged assemblies must be calculated with this expansion in mind.

Caprolon is unsuitable for chemically aggressive environments, including acids, alkalis and petroleum products at temperatures of +80°C and above. PTFE F-4 should be used under these conditions.

Can Caprolon replace bronze in plain bearings?

Caprolon can replace bronze in assemblies with sliding speeds of up to 2 m/s and specific loads of up to 10 MPa, provided that the operating temperature does not exceed +100°C. It requires no lubrication, does not produce abrasive wear debris and does not damage the steel shaft.

BrAZh or BrOTsS bronze remains the preferred material for high-speed, impact-loaded or high-temperature assemblies.