Drilling and workover rigs use a drawworks to pull up on thetubulars deployed into a well. The drawworks is attached to amast or derrick, which in turn is supported by the ground or afloating vessel. The tubular’s weight is not transferred to thewellhead.Coiled Tubing uses an injector head, instead of adrawworks, to pull and push tubing in and out of a well. Theinjector is generally mounted directly onto the wellhead,unavoidably transferring some of the reactive loads to thewellhead.These loads can be very substantial. They not only includethe tubing’s weight in the well but also loads generated by theCoiled Tubing on surface, that tubing which is being bent andpulled sideways. Often additional support is required to atleast partially isolate these loads from the wellhead. Thispaper identifies the various loads that Coiled Tubing impartsto a wellhead and how support mechanisms provide protectionto the wellhead.
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