COILED TUBING HAVING MULTIPLE STRINGS OF SMALLER TUBING EMBEDDED THEREIN

摘要

A single tractor unit (10) is provided for pulling a trailer (20), in which the tractor (10) itself drives a plurality of hydraulic motors which control a crane unit (46), a coiled tubing injection unit (44), and the pumps and moto rs associated with a liquid nitrogen system (38) which is used for injecting gaseous hydrogen into a workover well with coiled tubing. In an alternative mode, the liquid nitrogen system is replaced with one or more nitrogen generators (fig. 5) which gather nitrogen from the earth~s atmosphere to be pumped through the coiled tubing into the well being treated. Coiled tubing (306) is described which embeds one or more stainless steel tubes (302, 304) for transporting gas, liquid or other fluids therethrough and also includes the use of one or more cords (308, 310) which are used to assist in maintaining the coiled tubing as having a circular cross-section, with such cords either being electrical or non-electrical in nature.