摘要 |
FIELD: oil and gas industry. ^ SUBSTANCE: invention refers to oil and gas producing industry, particularly to block of back valves of system for pumping grout for cementing oil or gas wells. The block consists of a case with two parallel valve cavities, which from one side are closed with covers, while from the other side they communicate with cavities of inlet openings. In the middle part of each cavity of valves there are made conic seats for replaceable saddles. In a zone between the covers and seats the parallel valve cavities communicate between them and with the cavity of the outlet opening made in the case. The block of back valves is made removable and is designed to operate reliably when cement grout is used as a working body. ^ EFFECT: increased reliability of operation and serviceability due to possibility to replace worn details. ^ 6 cl, 3 dwg |