This standard specifies the product classification, technical requirements, inspection rules, marking and packaging of exhaust pipe steel flanges and gaskets with flange connection dimensions in accordance with GB 569 and GB 2501. This standard is applicable to stainless steel corrugated expansion joints and exhaust pipes of internal combustion engines with nominal pressures of 0.05 MPa and 0.10 MPa and operating temperatures not exceeding 550°C.