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TRUE-TAPER XR Enhancement
TRUE-TAPER XR coiled tubing string comprises individually tapered strips of steel, facilitating the welding of equal gauge material. This reduces stress concentrations, yielding improved fatigue performance.
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Description
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Resources
TRUE-TAPER XR is currently available for QT-900 through QT-1400 grades.
Recently, we have worked closely with our steel suppliers to develop shorter TRUE-TAPER XR taper sections that allows us to more precisely distribute the coiled tubing string weight in the lateral. Horizontal wells with long laterals require heavy-wall tubing in the vertical section to beyond the heel into the lateral. Once in the lateral, the string wall transition needs to go from heavy to light wall as quickly as possible. Quicker transitions may also result in a reduction of overall string weight, which is always welcome in today's ever-changing and demanding market.
As horizontal wells are consistently being drilled with longer laterals, it has become more challenging for coiled tubing to reach total depth (TD). Changes in coiled tubing string designs have shown that the use of shorter taper sections is essential in getting better results.
Working closely with a customer, we were able to reduce the total tapered section lengths of a 2⅜-in. QT-900 coiled tubing string design by 64.5% compared to a conventionally tapered design.
With conventional tapers, going from 0.224 to 0.134 in. would require four taper sections, and the total average length of the tapers going from 0.224 to 0.156 in. is approximately 4,315 ft.
- Taper one: 0.224 to 0.203 in.
- Taper two: 0.203 to 0.175 in.
- Taper three: 0.175 to 0.156 in.
- Taper four: 0.156 to 0.134 in.
With our new TRUE-TAPER XR tapers, going from 0.224 to 0.134 in. only requires two taper sections, and the total average length of the XR tapers going from 0.224 to 0.156 in. is approximately 1,530 ft.
- Taper one: 0.224 to 0.156 in.
- Taper two: 0.156 to 0.134 in
Advantages
- Internal wall steps at the bias weld eliminated, producing a smoother inside diameter (ID)
- Welding similar gauge material eliminates stress concentrations
- Higher usage to pipe in high-cycle and deviated well conditions due to fewer bias welds needed
- Achieves better reach in longer laterals
- Lighter overall coiled tubing string weight