Cast Nylons are a range of polyamides produced by a casting process involving the anionic polymerisation of caprolactum. This process allows the production of semi-finished plate, rod, tube and custom castings that are largely free of internal stresses. Natural Cast Nylon is the basic grade from which all other grades of Cast Nylons stem. Generally accepted as the primary engineering polymer, Natural Cast Nylon is suitable for virtually any plain bearing application not to mention a huge range of other applications for which this versatile grade finds a use. By varying the conditions of polymerisation the mechanical properties of Cast Nylon may be altered to suit specific applications and the addition of various additives, fillers, lubricants and colorants.
Compared with extrusion grades of polyamide (Nylon 66), Cast Nylons stand out with their improved mechanical, thermal, and chemical resistance properties. Specifically the material has a higher tensile, compressive and impact strength as well as an improved resistance to creep and heat ageing. The reasons for these improved characteristics are high crystalinity and a remarkably higher molecular weight. Due to low water absorption, mechanical properties and dimensions are more stable making it suited for components that have to meet closer tolerances. Cast Nylon has the ability to operate effectively without the need for lubricants and has an increased resistance to wear of over 5 times that for plain bearings manufactured from non-ferrous metals. As is the case with virtually all Nylons it is easy to machine, pleasant to work with and relatively light weight - 1/8 that of brass - making the handling and fitting of large components manufactured in Cast Nylon a relatively easy matter.
