Specifications Material:20# 45# 16Mn 27SiMn   ST52,BK+S,DIN2391,ASTM A 106 or according to your requirement. Standard: GB/T8713-88 GB/T3639-2000 DIN 2391 EN10305 or according to your requirement. Straightness:0.3~0.8mm/m or according to your requirement Elongation: 14%-25% or according to your requirement. ID tolerance:H7-H8 Application: Mining industry,   machinery processing,  natural gas oil transportation exploitation etc.   Process: Cold-drawn, cold-rolled, honed, SRB Delivery condition: BKS or according to customer's requirement Equipment: Cold drawn machine,honing machine,SRB machine,Point straightening machine,roller straightening machine,lathe