Jiangsu PP Flat Flange Wholesale - Price - Manufacturer Phone Number [Jiangsu Jiayuan Pipe Valve Fitting Co., Ltd.] Material: PP flat flanges are mainly made of polypropylene (PP). Polypropylene is a thermoplastic material with excellent chemical resistance, heat resistance, and mechanical strength, suitable for manufacturing various pipeline fittings. Features: PP flat flanges are corrosion-resistant, acid and alkali-resistant, and can withstand high temperatures (generally within the range of -7℃ to 100℃), meeting the usage requirements under various harsh conditions.