Drilling and workover rigs use a drawworks to pull up on the tubulars deployed into a well. The drawworks is attached to a mast or derrick, which in turn is supported by the ground or a floating vessel. The tubular's weight is not transferred to the wellhead. Coiled Tubing uses an injector head, instead of a drawworks, to pull and push tubing in and out of a well. The injector is generally mounted directly onto the wellhead, unavoidably transferring some of the reactive loads to the wellhead. These loads can be very substantial. They not only include the tubing's weight in the well but also loads generated by the Coiled Tubing on surface, that tubing which is being bent and pulled sideways. Often additional support is required to at least partially isolate these loads from the wellhead. This paper identifies the various loads that Coiled Tubing imparts to a wellhead and how support mechanisms provide protection to the wellhead.
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