MANUFACTURING OF PA PRODUCTS
The polyamides (PA) are macromolecules characterized by the presence of the amide CO – NH group. The range of existing polyamides is vast: the most widely used are the homopolymers and polyamides, which are distinguished in the macromolecules of the “AB” type (PA 6, PA 11 and PA 12) and in the macromolecules of the type “AA / BB” (PA 46, PA 66, PA 69, PA 610 and PA 612). The numbers in the abbreviations always refer to the number of carbon atoms present in the basic molecules. Then there are the copolymers polyamides (PA 66/6, PA 6/12 and PA 66/6/610), special polyamides (PA NDT / INDT, PA 6-I, PA 6-T, T-PA 9 and PA 6-6-T) and aromatic polyamides (PMPI and PPTA). A note of relief deserves the casting polyamides (PA 6 and PA 12-G-G), which have higher molecular weight and greater rigidity.
CHARACTERISTICS AND APPLICATION FIELDS
For polyamides are allowed all common processing systems to thermoplastic materials, so they can be printed, extruded, blown and worked mechanically. Rotary products are usually made by casting and by centrifugation, those cables. During the solidification the withdrawal amounts to 4-7%, during machining can get to 3%. Also you can submit of shrinkage cavities within the material. PAs are weldable by fusion and can be pasted; They are also particularly suitable for the machining with chip removal.
The various types of PA have generally similar characteristics. Dry (immediately after the thermoplastic processing) are hard and rather brittle; following the absorption of water become more tough and abrasion resistant (water absorption also leads to an increase of the size). The PA have excellent sliding properties and wear, are insensitive to dirt and are chemically resistant. The softening temperature is relatively low and consequently the PA can not be exposed to continuous loads, although they can be used at temperatures near the melting point. Increasing the temperature and the percentage of water, the electrical and mechanical characteristics worsen; decreasing the capacity of water absorption, also it decreases the permeability to steam. The PA are resistant to solvents, oils, greases, fuels, to just concentrated alkaline solutions, ketones and boiling water. They are not resistant to strong alkaline or acid concentrations. The PA can be added various substances (glass fibers, carbon fibers, gypsum, molybdenum sulfide, aluminum, copper, bronze, iron, zinc, nickel) which can improve the strength, elasticity, heat stability, the sliding behavior and wear. They can also be added dye.
The PA are used in all applications in which they are required high performance in terms of abrasion resistance, toughness, chemical resistance and creep behavior. PAs ensure low noise, low vibration and high fluidity. They are used for the production of technical articles such as bearings, gear wheels, rollers, screws, gaskets, sealing rings, gears, bearings, pulley, washers and caps. They must not forget the fittings elements, components for pumps, parts for carburetors, intake manifolds, for the electrical parts, pipes, coatings for cables, membranes, propellers, reservoirs and films.
Shown below are the most common PA trade names available at LIMA
|LM301||PA 6 + MoS2|
|LM311||PA 6 + 20% CARBON FIBER|
|LM303||CAST PA 6|
|LM304||CAST PA 6 + MoS2|
|LM305||CAST PA 6 + OIL|
|LM312||CAST PA 6 + GREEN PE|
|LM310||PA 6 XAU|
|LM307||BLACK PA 66 + 30% GLASS FIBER|
|LM308||PA 66 + MoS2|
|LM309||CAST PA 12|
|LM331||BLACK DEVLON V|
PA – TRADE NAMES
Shown below are the most common trade names for the PA material.
Please remember that LIMA can provide both generic materials and materials covered by trademark (ie that show the TM or ® endorsements), based on the requirements of the customer. If the customer wishes to details made of plastic material covered by trademark, LIMA will stock up directly by the holding company of the said trademark.