Black Pom Plastic Sprocket Wheel Plastic Gear

Black POM plastic sprocket wheels are chain-drive sprocket gears machined or injection-moulded from black POM (Delrin / Acetal / Polyacetal) — the engineering thermoplastic renowned for its dimensional stability, excellent wear resistance, and very low friction coefficient. POM plastic sprocket wheels engage roller chains at the sprocket tooth profile, transmitting torque in conveyor, agricultural, and industrial drive applications. POM's near-zero water absorption (0.17–0.20% at 23°C) ensures the sprocket tooth pitch remains accurately matched to the chain pitch in wet conveyor environments; its black carbon-black formulation provides UV stabilisation for outdoor applications and superior fatigue resistance under cyclic loading. Self-lubricating, corrosion-free, lightweight — POM plastic sprocket wheels are a direct replacement for steel and cast-iron sprockets where noise reduction, chemical resistance, and elimination of lubrication maintenance are the operational priorities.

Korea Ever-Power's black POM sprocket wheels are custom-made per drawing or sample. Quote within 24 hours. Mould lead time 25–35 days (simple: 15 days). Start from sample if no drawing. Video QC inspection with dimensions, surface, and packaging detail before delivery. As Korea Ever-Power's plastic gear range supplier, all products target the highest quality with comprehensive service.

Black POM Sprocket

UHMW-PE Sprocket

Large Sprocket

Moulding Shrinkage — Tooth Pitch Compensation

POM injection-moulded sprockets shrink approximately 0.022 mm/mm during cooling — a POM sprocket with a mould pitch diameter of 50 mm shrinks to 48.9 mm after moulding. Korea Ever-Power compensates for this shrinkage in the mould tool design by scaling the mould cavity dimensions to produce the specified pitch diameter after shrinkage. Correct shrinkage compensation is critical: under-compensated tooth pitch causes the chain link to ride high on the sprocket tooth tip rather than seating correctly in the tooth root, increasing tooth wear and chain elongation rate. Korea Ever-Power's mould engineering team applies the correct shrinkage factor for each POM grade and sprocket geometry.

Backlash — Below 0.5% for Long Life

For POM sprocket wheel and rack / chain drive applications, the backlash (clearance between chain link and sprocket tooth) should be maintained below 0.5% of the chain pitch to avoid premature wear. Excess backlash causes the chain link to impact the sprocket tooth flank on engagement rather than smoothly engaging — the impulse load is amplified and the tooth root stress exceeds the design allowable, accelerating fatigue crack initiation. Korea Ever-Power specifies and inspects tooth profile geometry on production samples to confirm backlash compliance before series production.

Load-Carrying Capacity — Curved Tooth Profile

The rack design must ensure the highest load-carrying capacity and reduce frictional heat — the same principle applies to sprocket tooth design. The curved tooth profile of a correctly designed POM sprocket distributes the chain link contact force over a larger tooth flank area than a flat-face profile, reducing peak contact stress and frictional heat generation. Load-sharing between multiple chain links simultaneously in contact with the sprocket further reduces the force per tooth. Korea Ever-Power applies standard sprocket tooth form BS/ISO standards for the specified chain pitch, ensuring correct load distribution geometry.

Circular Rack vs Rectangular Rack — Installation Notes

For circular POM sprocket racks (where teeth are cut on a rod so the sprocket rolls on a straight rack), these are generally weaker than rectangular rack configurations and require careful design. They should be installed with sleeve bearings or other radial supports, as they are unsuitable for continuous rotation under high radial loads without support. Korea Ever-Power supplies sleeve bearings and support bushings in compatible POM or UHMW-PE material as matched-component sets for circular rack and sprocket assemblies where bearing support is part of the system design.

Material Suitability — POM vs Acetal Voids

Some plastic materials may be detrimental to sprocket durability and performance. Acetal (POM homopolymer / Delrin) is known to be prone to voids in thick cross-sections — large-diameter, thick-face sprockets moulded from POM-H homopolymer may develop internal voids at the section centre if mould cooling is uneven. Korea Ever-Power uses POM copolymer (POM-C) as the standard grade for sprocket wheels, which is significantly less prone to void formation in thick sections. For very large or thick sprockets, CNC machining from POM-C extruded rod eliminates void risk entirely. Korea Ever-Power selects the correct POM grade for each sprocket geometry.

UV Stability of Black POM — Outdoor Applications

Natural (white) POM degrades under prolonged UV exposure — outdoor agricultural, marine, and construction machinery chain drive sprockets should always use black POM (carbon-black masterbatch formulation). Carbon black at 2–3% concentration in POM provides UV-absorption that extends outdoor service life from 6–12 months (natural POM) to > 5 years (black POM) under direct sunlight exposure in temperate climates. Korea Ever-Power's black POM sprocket wheels use UV-stabilised carbon-black POM-C as standard for all outdoor-rated sprocket orders.

Industrial Chain Conveyors

Black POM sprocket wheels as drive and tail sprockets in roller chain conveyor systems for automotive parts, consumer goods, and industrial component handling. The black UV-stable POM suits both indoor and outdoor conveyor installations; self-lubrication eliminates chain lubricant maintenance; noise reduction improves working environment compliance. Drop-in replacement for steel sprockets — same chain pitch and tooth count, significantly quieter and maintenance-free.

Agricultural Machinery Chain Drives

Black POM sprocket wheels in combine harvester grain elevator drives, seed drill chain mechanisms, and irrigation system drives. UV stabilisation ensures long outdoor service life; resistance to fertilisers, pesticides, and herbicides prevents the corrosion that limits steel sprocket life in direct agricultural chemical exposure; the elimination of chain lubrication maintenance reduces field service requirements for machinery operating far from service facilities.

Packaging and Printing Machinery

Black POM sprocket wheels in packaging line infeed/outfeed drives, printing press chain drives, and labelling machine timing drives. The black colour avoids product contamination detection issues (black particles from wear are not visible on white product surfaces — for food contact, white POM sprocket wheels are recommended). The self-lubrication and near-zero water absorption suit the varied operating environments of packaging and printing facilities.

Marine and Offshore Chain Drives

Black UV-stable POM sprocket wheels in yacht windlass drives, marine deck equipment chains, and offshore platform auxiliary chain drives. Salt water, UV exposure, and temperature cycling that rapidly corrode carbon steel sprockets have no degradation effect on POM. The elimination of grease lubrication (which washes off in water environments) and the corrosion-free property make black POM sprocket wheels the practical choice for marine chain drives where steel sprocket maintenance is prohibitively difficult.

DIY, Hobby, and Light Industrial

Black POM plastic sprocket wheels for home repairs, DIY models, and hobby chain drive mechanisms. Plastic gear sets are simple and powerful tools for making toys and hobby projects; black POM sprocket wheels are suitable for smaller hobby projects and for teaching gear reduction concepts in chain-drive electric equipment models. Many DIY and hobby products rely on sprocket wheels to function — Korea Ever-Power supplies both production industrial quantities and small sample orders for development and prototype use.

Light Vehicle and Bicycle Mechanisms

Black POM sprocket wheels in electric bicycle chainring assemblies, cargo bike drive components, and light vehicle chain drive mechanisms. POM's stiffness and dimensional stability suit the precision chain pitch alignment required for efficient bicycle-type chain drives. The UV stability of black POM suits outdoor cycling applications; the self-lubrication is particularly valued for chain drives in sealed hub or internally-routed cable housings where re-lubrication is not practically possible.

Is black POM (acetal) or UHMW-PE the better choice for a plastic sprocket wheel?

The choice depends on application requirements. Black POM (acetal) is better when: dimensional precision is critical (POM has the highest stiffness and lowest water absorption of standard engineering plastics — maintaining tooth pitch accuracy); temperature stability to 90°C continuous is required; or a hard, rigid sprocket surface is preferred for precise chain engagement. UHMW-PE is better when: maximum wear resistance is the priority (UHMW-PE wears 2–5× slower than POM under abrasive conditions); food-grade FDA compliance with chemical wash resistance is required; or the chain drive operates in a highly abrasive environment (grain dust, soil particles). Korea Ever-Power confirms the optimal material for your specific application — contact with chain speed, load, duty cycle, and environment details.

Can Korea Ever-Power supply matching black POM sprocket wheels for both sides of a conveyor (drive and idler)?

Yes — Korea Ever-Power supplies matched drive and idler black POM sprocket wheel sets with consistent tooth profile, pitch diameter, and bore/keyway specifications from the same production run. Matched sets ensure the chain tracks consistently across both sprockets without the pitch error misalignment that occurs when mixing sprockets from different manufacturers or different production batches. Korea Ever-Power can also supply different tooth counts (different-ratio sprockets) for drive and idler positions if speed reduction across the conveyor length is required. Contact Korea Ever-Power with your chain pitch, required sprocket sizes, and quantity for a comprehensive quotation.

"We manufacture agricultural trailers and replaced carbon steel chain drive sprockets with black POM sprockets from Korea Ever-Power on our grain unloading conveyor. After 2 seasons of field use: zero sprocket wear measurement. Chain elongation at season 2 end: 0.4 mm/m — within replacement limit. Lubrication eliminated: no mid-season re-greasing required in the field. UV stability confirmed: no surface crazing or chalking after outdoor storage. Cost per sprocket: 40% below equivalent stainless option that was previously used for its corrosion resistance."

Kim Tae-yang  |  Agricultural Equipment Design Engineer, Incheon Farm Machinery Co.  ·  Q2 2026

"We build chain conveyor systems for automotive parts factories and source black POM sprocket wheels from Korea Ever-Power for our standard conveyor range. Korea Ever-Power machines all our sprocket sizes (8 different pitch/tooth count combinations) from a single supplier. Dimensional check on incoming inspection: all within ±0.04 mm on pitch diameter. Chain tracking performance: no lateral drift at 0.8 m/s chain speed — confirming tooth pitch accuracy. Noise comparison: 8 dB(A) below steel sprockets at same conveyor speed. Korea Ever-Power's 24-hour quote response and 28-day delivery fit our project schedule reliably."

Lee Byeong-jun  |  Conveyor Systems Engineer, Gyeonggi Industrial Systems Co.  ·  Q4 2025