... 8", 3 1/2", 4" ,4 1/2", 5", 5 1/2" ,6 5/82.Steel grade: E75,X95,G105,S135 3.Certificates ... : API 5DP,NS-1 4. Length: R1: 5.3-7.9m ... R2: 8.5-11.5m R3:11.5-14.5m 5.Internal Coating : ... be carried out as per customer demand. In line with NS-1requirement. Proprietary product——Tool Joint 1.DPDS——Double Shoulder ...