Methods and apparatus for introducing a pig into a fluid system

摘要

A method and apparatus for introducing a pig into a fluid system is provided. The method comprises providing a coupling in a fluid system. The coupling itself can include a sleeve coupled to a pipe and an end cap. The end cap may include a collar handle and at least one engagement member. The engagement member facilitates selective engagement of the end cap with the sleeve. The end cap is rotated relative to the sleeve to disengage the engagement member from the groove and to open the end cap relative to the sleeve. The groove is configured so that the engagement member can be opened only when the line is de-pressurized. A pig is inserted through the sleeve and into the pipe. The end cap is then coupled to the sleeve by engaging the engagement member with the sleeve and rotating the end cap relative to the sleeve.