Heavy-walled drill pipes

Warranty period - 1 year.
Service life is 4 yrs.
Average MTBF 400 screws - unscrews.
Average life before the first re-cutting is not less than 3000 hours, including re-cutting not less than 18000 hours.
Mechanical properties:
TBT and TBTP with diameter of coupling and nipple dropouts up to and including 175 mm
Tensile strength not less than 965 MPa
Yield strength not less than 758 MPa;
Relative elongation not less than 13%
Impact toughness KCU value not less than 600 J/sq. m
Impact work KV value not less than 54 J
TBT and TBTP with socket and nipple diameters over 175 mm
Tensile strength not less than 931 MPa
Yield strength not less than 689 MPa;
Relative elongation not less than 13%
Impact toughness KCU value not less than 600 J/sq. m
Impact work KV value not less than 54 J
The hardness of TBT pipes shall be 302...364HB at a length of at least 550mm from the ends and 285...364HB at the rest of the pipe.
The hardness of TBTP pipes shall be 302...364HB at a length of at least 200mm from the ends and 285...364HB on the rest of the pipe.