Delrin is a brand name for an engineered thermal plastic. Celcon and Hostaform are similar brand names for slightly different formulas of the same material, Polyoxymethylene (POM). Delrin is used in precision fittings requiring high stiffness, low friction and excellent dimensional stability.
Wiki reports the following advantages of Delrin of Fittings.
• High abrasion resistance
• Low coefficient of friction
• High heat resistance
• Good electrical and dielectric properties
• Low water absorption
Wiki reports the following disadvantages, many of which can be engineered around. “, it is susceptible to polymer degradation catalyzed by acids, which is why both polymer types are stabilized. Both homopolymer and copolymer have chain end groups (introduced via end capping) which resist depolymerization. With the copolymer, the second unit normally is a C2 (ethylene glycol) or C4 (1,4-butanediol) unit, which is introduced via its cyclic acetal (which can be made from the diol and formaldehyde) or cyclic ether (e.g. ethylene oxide). These units resist chain cleavage, because the O-linkage is now no longer an acetal group, but an ether linkage, which is stable to hydrolysis. POM is sensitive to oxidation, and an anti-oxidant is normally added to molding grades of the material.” The point is this: engineered plastics are designed with specific applications in mind. The life of your fitting will be impacted by how the plastic is engineered, and it may be longer or shorter, depending on the application and how it is engineered.
Wiki reported Uses of Delrin:
Mechanical gears, sliding and guiding elements, housing parts, springs, chains, screws, nuts, fan wheels, pump parts, valve bodies.
Electrical Engineering: insulators, bobbins, connectors, parts for electronic devices such as televisions, telephones, etc.
Vehicle: Fuel sender unit, Light stock (including shifter for light, turn signal), power windows, door lock systems, articulated shells.
Model: Model Railway parts, such as bogies and handle bars. POM breaks under load slightly less than ABS, but in bright translucent colors, and not paintable.
Medical: insulin pen, Metered dose inhalers (MDI)
Furniture: hardware, locks, handles, hinges.
Construction: Structural Glass - pod holder for point
Packaging: aerosol cans, vehicle tanks.
Sports: Paintball accessories. It is often used for machined parts of paintball markers that do not require the strength of aluminum, such as handles and reciprocating bolts. POM is also used in airsoft guns, in order to reduce the noise of the piston.
Music: picks, Irish flutes, Bagpipes, Practice chanters, harpsichord plectra, tuba mouthpieces.
Dining: Fully automatic coffee brewers; knife handles (particularly folding knives)
The Food and Drug Administration has approved Delrin for use in the food industry.
Horology: Watch bracelets (e.g. IWC Porsche Design 3701)