| 摘要 |
This invention relates to releasable couplings for long lengths of tube and rod, in particular for coupling long-length flexible tubes (coiled tubing), long-length flexible rod, and also for boring and casing pipes, production tubing and collapsible pipelines. The present releasable coupling for flexible long-length tubes consists of threaded nipples, mounted on the ends of tubes that are to be connected, with projections on the end of one nipple and corresponding grooves on the end of another nipple, and a threaded sleeve, wherein the thread on the two nipples has a different pitch and the threaded sleeve has two threaded portions, wherein the pitch of the thread on each of these portions corresponds to the pitch of the thread of the corresponding nipple for the mutual coupling thereof, and the thread on all of the connected coupling elements is oriented in the same direction, wherein the nipple with the larger pitch is provided with a runout in the form of a cylindrical groove or non-threaded portion of the nipple, the length of which plus the distance through which the tubes to be connected mutually advance until a tight connection occurs is greater than the length of the larger-pitch thread on the sleeve. The result is an increase in the reliability, durability and tightness of the coupling. |
