High Strength Welded HWDP

According to the feedback from oil field,   there are so many problems such as operating environment contain hydrogen sulfide , bad wear feature, short retirement period and so on, JSH manufacture high strength welded heavy weight drill pipe. Yield strength and hardness range can be controlled, lower C,  S content, be more suitable for environments which containing hydrogen sulfide.

High strength welded heavy weight drill pipe friction welded by 4130M pipe body and 4145H/4137/4130 tool joints. Pipes and tool joints needing quenching and tempering treatment, heat treatment carry out in whole welded zone. In accordance with the yield strength, it can be divided into 75, 90 S, 95, 110 and 120 grade.

The feedback are very good after application by Sinopec and some oilfields. 

Chemical composition requirements of HWDP and tool joint

Tensile Requirement of HWDP body,   tool joint and welding zone

Impingability Requirement of HWDP body,   tool joint and welding zone

Requirement of hardness

The hardness of tool joint surface-after final heat treatment,   hardness grooving shall taken on each joint’s surface then carry out the hardness test on the surface,  hardness range should be 285-341HB.   

The hardness of wall thickness-In accordance with ASTM A370 standard,   to take a radial cross section from the body /tool joint ,   the section need turning or grinding flat. 

Rockwell / Brinell hardness test taken on outer,   middle and inner. Maximum of wall thickness is HRC22,  tool joint hardness should be 293-331HB.

The hardness for both welding zone and cross section should  be less than HRC37,  and  no more than HRC5 when the hardness in the same section along the thickness direction.

Requirement of metal microstructure

Grain should be 6 or higher ( in accordance with ASTM E112 standard ) , not allowed to exist untemper Martensite and coarse overheated structure, various  non-metallic inclusion microanalysis level ( in accordance with the ASEM E45 A method ) should be less than Level 2.5