Product specifications: diameter (8~400mm) × length (optional)
Product level: Level A
POM rod (Polyoxymethylene rod, also known as acetal rod) is a high-performance engineering plastic profile made of Polyoxymethylene, which is divided into two types: homopolyoxymethylene (POM-H) and copolymerized polyoxymethylene (POM-C). Its core product characteristics are as follows:
1. Physical properties
Density: approximately 1.41-1.43 g/cm³, heavier than nylon (PA) and PP, but with higher mechanical strength.
Temerature resistance: It can withstand short-term temperatures up to 100-140℃, and for long-term use, the temperature range is approximately -40℃ to 100℃ (the temperature resistance of homopolymethylene is slightly higher than that of copolymethylene).
Color and specifications: Commonly available in white, black, or beige, with customization options;
Dimensional stability: Low water absorption (water absorption rate < 0.2%), with minimal dimensional changes in humid environments.
2. Chemical properties
Solvent resistance: Resistant to organic solvents such as hydrocarbons, alcohols, and esters, but sensitive to strong acids (such as concentrated sulfuric acid and nitric acid), strong alkalis, and chlorinated hydrocarbons (such as trichloroethylene).
Oil resistance: Excellent resistance to grease and lubricating oil, suitable for mechanical lubrication environments.
Weather resistance: Long-term exposure to ultraviolet light is prone to aging, necessitating the addition of UV stabilizers.
3. Mechanical properties
High strength and rigidity: The tensile strength is as high as 60-70 MPa (even higher for homopolyoxymethylene), and the hardness is close to that of metal, far exceeding that of polypropylene (PP) and nylon.
Wear resistance: With an extremely low friction coefficient and excellent self-lubricating properties, it is suitable for high-load and high-speed components such as gears and bearings.
Fatigue resistance: It maintains stable performance under cyclic stress and exhibits outstanding creep resistance.
Impact resistance: It maintains good toughness even at low temperatures (-40℃) without the risk of brittle fracture.
4. Processing performance
Workability: It can be precisely processed through turning, milling, drilling, etc., but the cutting speed needs to be controlled (to avoid overheating and melting).
Injection molding: Requires high temperature (190-230℃) injection molding, with good melt flowability, suitable for complex structural parts.
Bonding and welding: Solvent bonding or hot plate welding can be used, but the bonding strength is relatively low.
5. Application areas
Precision machinery: high-precision wear-resistant components such as gears, bearings, cams, pump valves, etc.
Automotive industry: fuel system components, seat belt buckles, and window regulators.
Electronic appliances: gear transmission mechanism, connector, insulating parts.
Daily necessities: zippers, spray nozzles, sports equipment accessories.
6. Limitations
Poor acid resistance: It is prone to corrosion in strong acid and oxidizing environments.
Easy to decompose at high temperatures: Formaldehyde gas may be released when processed or used at temperatures exceeding 140°C (ventilation required).
High cost: The price is higher than that of PP and some nylon models, but lower than that of special engineering plastics (such as PEEK).
