How are PVC profiles for plastic-steel doors and windows produced?

Plastic-steel door and window profiles are mainly produced by PVC extrusion. Raw materials are mixed first, then plasticized, shaped by mould, cooled, pulled, cut and inspected to get finished products. Due to complex cross-section, dimension control is critical. Stable equipment, mould and process ensure quality. Buyers should focus on long-term batch stability to improve processing efficiency.