API-5CT N80 oilfield casing pipe containsN80-1 and N80-Q types. Those two materials are absolutely consistent regarding the chemical composition and mechanical attributes, they are
just various in the heat treatment.
During heat treatment, N80-1 steel is treated by normalizing and tempering, while N80Q steel is treated by quenching and tempering.
Therefore, the collapsing strength and internal pressure strength of N80Q are higher than that of N80-1. N80-1 or N80Q should be clearly shown by the designer when N80 casing is selected.
As its mechanical properties are higher than J55 and K55 types, it may very well be utilized to certain a little more challenging
formations. With deeper downhole depth than J55 and K55 types, it can be applied for the exploitation of middle-level oil and gas.
Due to the high capability of N80 material, those API-5CT casing pipes are broadly applied in natural gas as well as coal bed
methane extraction, and geothermal wells.
API 5CT N80 Casing Tubing Features
●API 5CT N80 Casing Tubing is offered with a free length range from 8 to 13m on basis of
the SY/T6194-96 norm. However, it is also available no less than 6m length and its quantity should be no more than 20%
●Any deformation such as crease, hairline, separation, crack or scab is not acceptable
on both inner and outer surfaces of the product. All these defects should be completely removed, and the removed depth must not exceed 12.5% of nominal wall thickness.
●Deformations which mentioned above are not allowed to appear on the outer surface of API
5CT N80 Casing Tubing coupling
●The surface of thread of coupling and API 5CT N80 Casing Tubing should be smooth without
any burr, tear or other defects that may have a negative impact on the strength and close connection.