| 摘要 |
The device is to be used in the drilling and operating of various wells, and also in the construction and operation of surface pipeline systems. The device comprises a body 1, a stop valve 2, a potential energy accumulator 3 and a holding-lowering mechanism 5. The accumulator 3 is in the form of a spring, and the mechanism 5 is immovably fixed in the body 1 and is equipped with fixing elements 6. The valve 2 comprises a seat 7 and a disc 14 in the form of a drum. The outer surface 17 of the disc 14 has a conical groove 18 for the fixing elements 6. A lubricant-filled cavity 25 for the mechanism 5 is formed between the body 1 and surface 17, filled with a lubricant. On the inside the disc 14 has a through passage for a flow 19 with a surface of conical shape 22, which expands from the inlet 20 to the outlet 21, and with a surface of cylindrical shape 23 at the outlet 21. The disc 14 comprises a replaceable connecting piece 24, installed in the passage 19, on the inlet 20. The seat 7 comprises circulation passages 9 on an annular part 8 and has a boss 10, which is formed by a cylindrical surface 11 and by a spherical surface 12 with a spherical end 13. The technical solution provides maximum normative intensity of flow pass-through, controls closing and opening of the cut-off device, improves reliability of the cut-off device for safe operation and widens its applicability. 2 subclaims, 1 illustration. |
