Polyoxymethylene Balls (POM/Acetal) for Valves and Precision Mechanisms
REDHILL supplies POM balls, also known as acetal or polyoxymethylene balls, in POM-H and POM-C grades. They combine low friction with stiffness and wear resistance. As a result, they suit valves, guides and lightly loaded bearings.
Key Technical Specifications
The values below describe typical unfilled materials. However, the grade, additives and test conditions affect the final properties.
- Material Options: POM-H homopolymer and POM-C copolymer.
- Structure: Semi-crystalline thermoplastic.
- Hardness: Approximately 80–85 Shore D.
- Density: Approximately 1.40–1.43 g/cm³.
- Typical Upper Service Temperature in Air: Around 90–110°C, subject to grade and load.
- Electrical and Magnetic Properties: Unfilled grades provide electrical insulation and show no magnetic response.
Choosing POM-H or POM-C
POM-H generally offers higher strength and stiffness than POM-C. Therefore, it suits mechanisms where rigidity and mechanical strength guide material choice.
POM-C generally offers better resistance to hot water and a wider range of chemicals. However, check each fluid and cleaning agent at the working temperature.
Low friction helps reduce sliding resistance. In addition, low moisture absorption helps limit changes in ball size.
Applications of POM Balls
For example, common applications include:
- Light-Duty Bearings: Rolling elements for low-load mechanisms.
- Valves and Dispensers: Check balls and closing elements.
- Pumps and Flow Meters: Moving parts for compatible fluids.
- Precision Mechanisms and Guides: Contact elements for controlled motion.
Also, confirm whether the material suits dry running at the intended load and speed. The mating surface and lubrication affect wear and service life.
Available Grades and Sizes
- Precision Classes: GI, GII and GIII, subject to the agreed tolerance specification.
- Diameter Range: 1/16 in–4 in, approximately 1.59 mm–101.6 mm.
Finally, send us the POM type, diameter, tolerance and quantity. In addition, include the fluid, load, speed and operating temperature. We can then confirm suitable options and lead time.