High-Quality Plastic Ring Exporters & Products

Utilizing our horizontal centrifugal monomer polymerization drums, SHUNDA can produce cast MC nylon rings up to an outer diameter (OD) of 2,200 mm with radial wall thicknesses ranging from 4 mm to over 150 mm. For POM-C, continuous extrusion rods and thick-walled tubes support machined ring diameters up to 500 mm.

Polyamide 6 naturally absorbs ambient moisture (up to 3.0% under normal humidity, reaching 8.5% at total saturation), expanding physical dimensions by 0.2% to 0.3% per 1% moisture absorption. For close-tolerance applications (ISO fit H7/f7), we perform water-conditioning pre-treatment prior to final CNC turning, or recommend dimensional offset programming or using chemically stable POM-C or PTFE.

Yes. We routinely supply split backup rings and piston guide rings with 30°/45° scarf cuts, lap/step joints, and standard straight radial butt cuts. Precision wire EDM and fine-blade high-speed indexing saw cutting ensure minimal kerf loss and pristine mating edges without heat deformation.

For rigid engineering thermoplastics like POM-C and PEEK, we reliably hold ±0.010 mm on inner/outer diameters and ±0.005 mm on axial heights. For large-diameter thin-walled cast nylon rings, we employ custom pie-jaw chucks and vacuum holding plates to counteract elastic deflection, achieving ISO 2768-mK or customer-specified GD&T circularity tolerances.

Standard polyurethanes and cast nylons can suffer from gradual hydrolytic attack in hot water-glycol solutions above 50°C. For these systems, we recommend our specialized high-crystalline POM-C (Polyacetal copolymer) or bronze-filled PTFE compounds, which offer indefinite hydrolytic stability and zero swelling in HFA, HFB, and HFC fluids.

Rapid prototyping or initial sampling is typically completed within 3 to 5 business days upon drawing signoff (STEP/DXF/PDF). Standard commercial production batches (500 to 50,000 units) ship in 12 to 18 calendar days, accelerated by our expansive raw tube and rod stock inventory located directly on site in our Hebei manufacturing complex.