Differences Between API 5CT N80-1 and N80Q
POSTED ON 2017-07-12
Main difference for API 5CT N80-1 and N80Q.
In API 5CT specification, for grade N80 there are two different level N80-1 and N80Q. The same part is both N80-1 and N80Q casing pipe have same tensile strength. The different part is impact properties and delivery condition. N80-1 delivery condition is normalizing. The final hot rolled temperature is higher than critical temperature Ar3, and after stretch reducing and air cooling, so could use hot rolled process replace the normalizing. Impact test properties and Non-destructive test is not required.
API 5CT N80 casing manufacturing processes
Like other grades of API 5CT, manufacturing processes includes hot rolled in seamless and ERW welded. In most of the cases the casing pipe adopts the seamless type.
Connection type, ends and Couplings
N80 casing pipe connection type usually refer to BTC, which is buttress thread marked with BC symbol; Other than this type there are short round and long round thread types, corresponding marked as SC or LC symbol. Octal also specialized in supplying premium connections in different types, air proof casing connections. And in case client required, we could customize connection threads and couplings.
Inspection Method
Size and surface inspection
NDT and pressure test and third party certication
Hydrostatic
Drifting test
Physical and chemicail analysis
Hardness and pressure test.
Electromagnetic
Magnetic particle
Ultrasonic
Oilfield API 5CT Casing Pipe L80-1, L80-9Cr, L80-13Cr.
Grade L80 casing pipe, divided in L80-1, L80-9Cr, and L80-13Cr, their mechanical strength and delivery condition is the same. The different part is on the application, production processes, cost and price. L80-1 is the general type, L80-9Cr and L80-13Cr are of the high resistance to rot, production processes is complicated and cost high, generally usually used at the oil well with heavy corrosion.
