The roundness of the eccentric reducer should not exceed 1% of the corresponding outer diameter at the ends, with an allowable deviation of ±3mm. The material of the eccentric reducer complies with SY/T5037, GB/T9711, GB/T8163, ASME ASTM A106/A53 GRB, API 5L, APT5CT, ASTM A105, ASTM A234, ASTM A106, DIN German standards, and customer-specified standards. The eccentric reducer (reducer bushing) is a type of pipe fitting used at pipe diameter changes. The commonly used forming processes include necking down, expanding, or a combination of both. For certain specifications, stamping forming can also be applied.