Cementing head
Cementing head is a device installed on the top of casing during cementing. During cementing operations, a cement plug for cementing is pre-placed in the cement head, including an upper plug and a lower plug. Put in the lower plug before injecting the cement slurry, and then put the upper plug on the upper plug after the predetermined amount of cement slurry is poured, and then substitute the mud or clear water to make the upper plug go down. When the lower plug is blocked by the supporting ring, the partition in the center hole is broken until the cement slurry is completely squeezed out of the casing. When the upper and lower plugs collide, the liquid channel is blocked, the pump pressure suddenly increases, and the cement is injected. End. After the cement injection, close the gate leading to the outside of the cement head and remove the connecting pipeline.
Cement casing head
When the lower cement plug is released, it rotates to exit and releases the lower stop pin. The lower cement plug leaves the inner cavity of the lower cement plug under the push of gravity and pumping liquid (the release indicator pin is shown), and is driven to the casing along the inner wall of the casing. On the floating hoop. When the cement plug is put on, rotate and exit to release the upper stop pin. The upper cement plug is pushed by gravity and displacement fluid to leave the inner cavity where the upper cement plug is located (the release indicator pin is shown), displace the cement slurry and clean the inner wall of the casing Until it coincides with the lower rubber stopper and hits it.
Liner cement head
The liner cement head is used for liner cementing. The stern tube cement head is composed of lifting pup joint, body, rotating bearing mechanism, drill rod stopper pin mechanism, ball throwing mechanism, drill rod connection pup joint and valve manifold, as shown in the figure. The stern tube cement head is mainly used for stern tube cementing, and the functions of the lifting sub and rotating bearing mechanism are the same as the corresponding mechanism of the drill pipe cement head. When the tail pipe hanger is seated, rotate the handle of the pitching mechanism, and the ejector rod will eject the ball from the inner cavity of the pitching mechanism. The ball is pushed by gravity and pumped liquid and falls on the hanger ball seat along the inner cavity of the drill rod. , Under the action of pump pressure, the tail pipe hanger can be seated. When releasing the tail pipe rubber plug, rotate the handle of the drill pipe stopper pin mechanism to retract the stop pin from the inner cavity of the drill pipe plug, and the drill pipe plug will leave the inner cavity of the drill pipe plug under the push of the pumped liquid and move along the drill pipe The inner wall falls on the rubber plug seat of the tail pipe, and the rubber plug of the tail pipe is cut and released under the action of the pump pressure.
