NC38 Inside blowout control tools 3~3/8" Upper / Lower kelly valves
Product information
Kelly cock valve is a manual control valve in the drill string circulation system and is one of the effective tools to prevent blowout; it is upper Kelly valve and lower Kelly valve which is assembled the upper end and lower end of drill pipe.
The kelly valve can be opened on or closed off by the specoal operating spanner at 90 degrees according to the indicatong dorection.
| Model | O.D. | I.D. | Connection | WP |
mm(inch) | mm(inch) | API | 35MPa 70MPa 105MPa |
Upper Kelly Valve | XS197 | 197(7-3/4) | 76.2(3) | 6-5/8REG LH |
XS146 | 146(5-3/4) | 44.4(1-3/4) | 4-1/2REG LH |
Lower Kelly Valve | XS111 | 111(4-3/8) | 38(1-37/64) | NC31 |
XS121 | 121(4-3/4) | 44.4(1-3/4) | NC38 |
XS146 | 146(5-3/4) |
XS165 | 165(6-1/2) | 71.4(2-13/16) | NC50 |
XS178 | 178(7) | NC50 |
XS184 | 184(7-1/4) | 5-1/2FH |
The kelly valve has simple structure, convenient operation and reliable use. It has become an important part of the blowout prevention system in the drilling string and is widely used in the field.
There are three main failure modes of the kelly plug valve:
①The strength failure is mainly caused by the early fatigue fracture of the valve body. The reason for the strength failure is the unreasonable structure size, poor material, and improper heat treatment;
②The ball of the valve fails to rotate. This is because the frictional torque between the ball and the valve seat is too large, severely rusted, the valve seat is plastically deformed and the sealing surface is stuck with solid particles. The root cause of the rotation failure is the gap between the ball and the valve seat. Caused by excessive friction;
③Seal failure, the sealing structure of the plug valve consists of three parts, of which the main seal between the ball and the upper valve seat is particularly important. If it fails, the function of the plug valve as a stop valve will be completely lost. For this reason, on the basis of failure analysis, measures to reduce the above three types of failures are proposed.
production name:kelly valves
Style and size: OD5 3/4", 4 1/2IF , 5000PSI
Connection: NC38
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Company introduce
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KSQ Technologies (Beijing) Co. Ltd. is a company that shall cater to the needs of the construction and mining industries, with consideration on providing solutions to the following unique problems:
- Hazardous environment
- Acts, regulations, and other government guidelines that has to be followed
- Significant differences in the way people work, mostly due to physical constraints
- Avoiding downtime on major equipment which can cost tens of thousands of dollars per hour. The best solution with the most reasonable cost is a significant driver.
Company Information
KSQ Technologies (Beijing) Co. Ltd. has significant experience and know-how in the supply of materials, components, finished goods, specially designed/engineered equipment, and services from China. The company caters to medium to large scale clients who are doing projects and capital expansion, as well as to firms who require support with consumable products, maintenance, and repair operations.