Wash pipe is a tool string component used along with a burn shoe for operations involving wash over. Wash pipe generally has a comparatively bulky interior diameter and has a tubular shape. It can be washed over a fish that is in preparation for attracting the fish and thereon retrieving it.
Under the standard drilling conditions the mud pressure is generally up to 3,000 PSI. In such conditions the traditional wash pipe along with the packing lasts for as many as 800 hours at the maximum. On the other hand, as pressure keeps rising above 5,000 PSI, the traditional wash pipe systems may fail in under 100 hours only which can often go down to a 50 hours as the pressure continues to rise at a very fast rate. Wash pipes system of the hydrodynamic kind are on the other hand capable of operating at pressures up to 7,500 PSI in the midst of noticeably prolonged service life, thereby going for fewer operation suspensions, lessening the danger to crew members who have to take part in the change out. In accordance with that the outmoded lubricator circuit, the downtime preservation can be planned at a further opportune process rather than the closing down of the drilling and thereon pulling out of the hole to replace a failed seal in the pipe.
In case of the traditional modes of the common packing arrangements, each and every seal in the pipe does its entire work until it fails and the tuck breaks off. In such a situation the entire working effort is passed on to the next seal on the pipe. Wash pipes have hydrodynamic packing box where in every seal performs the same carve up of the work from the very launch, ensuing in a longer lasting seal. Wash pipe system that is hydrodynamic in nature helps reduce the entire force drop across the length of the seals by pumping in the oil that is kept under pressure into the hollow space following the seal.
Pipe pressure on the rear side of the seal is in fact higher than the force on the drilling liquid side of the seal. Wash seal itself is intended to “glide” on the oil, a lot like the tyres of a car that hydroplane on a wet road. As a result there is a trivial quantity of oil seeping beneath the seal. Pipe safety is ensured this way as the drilling fluid does not approach into contact with or mortify the seal itself any more.
Pipe of this kind that are used for washing purposes gain a prolonged service life thanks to the cautious application of the leak that plays an immensely effective role all together.