API 5CT J55 and K55 Oil Casing Tubing

API 5CT J55 and K55 Oil Casing including short round thread casing (STC), long round thread casing (LTC) and buttress thread casing (BTC). STC and LTC both feature a non–runout design of round threads

• STC (Short Thread Coupled)
• BTC (Buttress Thread Coupled)
• LTC (Long Thread Coupled)
• EUE (External Upset End)
• NUE (Non Upset End)
• LP (Line Pipe)
  casing pipes of grades J55, K55 are a popular choice for wells without stringent anti-corrosion or strength requirements.In this article we will introduce the difference between K55 and J55.Tubing: PSL1, J55 and K55 have no requirement; PSL2 J55 and K55 require minimum impact work 20J of full size specimen, and minimum impact work 27J of full size specimen.

  ●Chemical composition and physical properties

  API grade K55 has the same Chemical composition as grade J55 ,they both has the same yield , but its minimum tensile strength is about 26% higher compared to J55.

  J55

  Yield strength: 379-552 MPa (55-80 ksi),

  Minimum tensile strength: 517 MPa (75 ksi)

  K55

  Yield strength: 379-552 MPa (55-80 ksi),

  Minimum tensile strength: 665 MPa (95 ksi)

  ●Heat treatment (PSL2 and PSL1 are different)

  API 5CT J55 PSL1 and API 5CT K55 PSL2 is the same (Rolling delivery);

  API 5CT J55 and K55 Oil Casing is mainly used for shallow oil and gas extraction, especially in natural gas and coal bed methane exploitation. It is also most often used in shallow wells, geothermal wells, and water wells.