The API external-upset-end (EUE) tubing pipe is broadly used due to the fact that is a good, serviceable interconnection in the majority of wells.

Without the need of modifying the actual thread shape, the joint dimension will increase because of  upsetting procedure. The EUE joint features a designed joint strength in tension and pressure strength much higher than that of the pipe overall body and, as a result, is considered a 100% joint effective connection.

To enhance  seal efficiency of API EUE tubing in high-pressure system, a grooved coupling, which accepts nonmetallic seal rings, is quite often applied in the coupling (see API Spec. 5CT SR 13).

API EUE joints come in OD sizes of 1.050 to 4.500 inch.

Specifications

Tolerances

Mechanical Properties

Inspection

Physical properties are checked and each length hydrostatically tested, normally to only 3,000 psi in the plain end (unthreaded) condition. The following are also checked:

• Dimensions
• Weights
• Straightness
• Lengths

Part of this inspection is to drift all lengths.
Despite all the American Petroleum Institute (API) specifications and testing, some tubing defects are still found after delivery; thus, some operators do further inspection.

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