High Pressure RD Circulating Valve Full H2S Service Well Testing DST Tool

Introudction of Multi Cycle Circulating Valve

Multi-cycle circulating valve is a kind of circulating valve, which is used in well testing service. The valve made of Inconel alloy steel is served in Full H2S well condition. The multi-cycle circulating valve is acceptable for the full-opening formation testing in cased hole, oil tube tradition perforation, tube string testing and cycle operation in the conjunction of perforation and full-opening formation testing. The multi-cycle circulating valve overcomes the shortcomings of some other circulating valve, at a certain position, can use the annulus pressure to operate other tools many times and there is no influence upon the multi-cycle circulating valve

Working principle of Multi Cycle Circulating Valve

Multi-cycle circulating valve completes the function by increasing and releasing the annulus pressure .

According to the construction features it can be learned when increasing the annulus pressure, the piston push the hydraulic oil to move to the left, and the hydraulic oil push the check valve assemblies to move to the left until to the upper dead point, then the hydraulic oil pass the passageway and push the floating piston in the nitrogen chamber, thus the pressure is saved in the nitrogen chamber.

When releasing the pressure, because the pressure in nitrogen chamber is above the annulus

pressure ,the nitrogen pressure push the floating piston in the nitrogen chamber and then to hydraulic oil move to the right, the check valve assemblies to move to the right under pushing of hydraulic oil until

to the lower dead point, the hydraulic oil make the nitrogen pressure equal to the annulus pressure.

Technical parameter of Multi-cycle circulating valve

Well Testing Multi Cycle Circulating Valve High Pressure Full H2S Service DST

HSE﹡Safety instructions:

* When running each pressure test, the pressure must be increased gradually. When the pressure is up

to 20MPa, hold on for one minute, then every 10MPa keep it for one minute until the rating pressure;

* During pressure testing, the DST tool should be placed in the test pit and cover the protecting board on

the pressure test plug.

* During the whole testing process, make sure the entire test operator keep away from plug and joint

which may lapse.

* Test area should set isolation, others except operator not allowed to enter test area.

* If there is anybody in the test area, it should set isolation, avoiding test production fly off the test area.