CN87210737U - Step-support type casinghead - Google Patents

Abstract

The utility model relates to a step-support type casing head belonging to a sealing device which is used between a surface casing and a lining casing of an oil and gas well head, comprising a bearing plate, a slip bowl, a wedge hinge type clamping mechanism, a seal ring, an upper washer and a lower washer. The device can not only make the free pipe at the optimum verticality so as to prevent the harm of the torsional deformation, but also can efficaciously cancel the defect of the rotary motion of the interior jacket tube string when landing joint is disassembled. The utility model has the advantages of light weight, small size, simple structure, convenient installation and low cost.

Description

Step-support type casinghead

The utility model belongs to a kind of oil gas well wellhead assembly, is the step support formula casing head that is used for plaing between surface pipe and the inner layer sleeve sealing effect.

At present, oil gas well well head surface pipe connects and sealing with inner layer sleeve, extensively adopts doughnut-shaped steel plate welding and first two method of slip-type casing tube.The doughnut-shaped steel plate welding is to utilize doughnut-shaped steel plate that surface pipe and inner layer sleeve is integrally welded securely, adopts this method, and the intensity at inner layer sleeve weld bond place is reduced, and easily ruptures, and causes the distortion of free pipeline section.The slip-type casing tube head is to be connected with the surface pipe box cupling by pipe nipple, utilizes the taper slips to block inner layer sleeve, is connected with production tree by counter flange.Though this device has the intensity height, good seal performance, the advantage that the inner layer sleeve damage is very little, when dismounting connected epimerite, because the slips clamping force is not enough, inner layer sleeve often rotated along with connecting epimerite.And this device is high more than one meter, and weight reaches 1.2 tons, and these bring a lot of inconvenience to well cementing operation.

Task of the present utility model provides a kind of employing step support inner layer sleeve load, by the step support formula casing head of gravity self-locking sealing and anti-rotation clamping body.The slip spider and the surface pipe of this device are welded into one, and inner layer sleeve is sitting in by its TC on the bearing plate of casing head and hangs, avoided because of welding to the harm that inner layer sleeve brings, overcome the disadvantage of free pipeline section easy deformation.Especially the wedge shape hinge type clamping body that adopts of this device, the inner layer sleeve string is with the hidden danger of changeing when having eliminated dismounting effectively and connecting epimerite, and this is the distinctive feature that this device is superior to the slip-type casing tube head.

The utility model is to realize like this, now in conjunction with the accompanying drawings, illustrated: it by bearing plate 2, taper jackscrew 3, slip spider 4, wedge shape hinge clamping body 5, sealing ring 7, put and press hole 8, lower gasket 9, upper gasket 10, positioning checkpoint 11, set bolt 13, technology backing plate 14 to form.When inner layer sleeve during down to last root, with bottom's (reserving the elevator position) that bearing plate 2 and upper gasket 10 are inserted in this casing coupling 1, with a technology clamp, the bottom of being close to upper gasket 10 is stuck on the inner layer sleeve 15, so that hold upper gasket 10 and bearing plate 2.The company's of connecting epimerite 12 is also mentioned the lower tube string, and bearing plate 2 and packing ring 10 are moved on to casing coupling 1 place of getting out of a predicament or an embarrassing situation, along with pipe is gone here and there in the lower going-into-well.After the well cementation, determine step support formula casing head installation site according to well-log information, unnecessary surface pipe is sliced off, then backing plate 14 is placed on the cross section of surface pipe 6, the two halves slip spider 4 of symmetry is placed on the technology backing plate 14, and conical screw 3 and wedge shape hinge type clamping body 5 transferred to the inoperative position, and align slip spider 4, put into lower gasket 9, chucking positioning checkpoint 11, tighten set bolt 13, the joint along two halves slip spider 4 welds it.Sealing ring 7 is packed in the annular space of slip spider 4 and inner layer sleeve 15, take out technology backing plate 14, slip spider 4 is put into surface pipe 6.Then slip spider 4 and surface pipe 6 are welded along groove.At this moment, dismantle and be used for holding the technology clamp of upper gasket 10 and bearing plate 2.Transfer inner layer sleeve, bearing plate 2 and upper gasket 10 are seated in the slip spider 4 under action of gravity, compresses seal 7 seals the inner layer sleeve 15 and the annular space of slip spider 4, and 15 ° of step places of bearing plate 2 external surfaces are sitting on 15 ° of steps of slip spider 4 inner surfaces simultaneously.Continue to transfer inner layer sleeve 15 until whole load are pressed on the bearing plate 2, bearing plate 2 is welded along external diameter and slip spider 4, so far this device installs.If have the release phenomenon to take place in process of production, but cone governor shape screw 3 forced seals.During dismounting landing joint 12, earlier the lead screw 5-a in the wedge shape hinge type clamping body 5 is screwed, make slips sheet 5-C block inner layer sleeve 15, unload landing joint 12 again.If casing pressure when too high, can press hole 8 put pressure by putting.

The utility model is simple in structure, and intensity height, supporting capacity can reach 50 tons, 25 centimeters of heights, and 85 kilograms of weight are convenient to install, and cost only is 1/10 of a slip-type casing tube head.Use this device can make free section sleeve pipe be in best plumbness, overcome the yielding disadvantage of free pipeline section, the inner layer pipe string is with the hidden danger of changeing when having eliminated the dismounting landing joint effectively.

Accompanying drawing is a structure chart of the present utility model.

The utility model is provided by following examples in conjunction with the accompanying drawings.

Slip spider 4 is that the two halves by symmetry are welded, in adorn two semicircle lower gaskets 9, the cross section is the sealing ring 7 of V-arrangement, annular upper gasket 10 and external surface have the annular bearing plate 2 of 15 ° of steps.Bearing plate 2 internal diameters cooperate with inner layer sleeve 15 external diameters, and its external diameter cooperates with slip spider 4 internal diameters.Under action of gravity, sealing ring 7 is compressed to when a certain amount of, and 15 ° of step places of bearing plate 2 external surfaces just occupy stably on 15 ° of steps of slip spider 4 inner surfaces, the weight of the whole inner layer pipe string of support.At even three screwed holes that distribute of slip spider 4 upper side, to penetrate three conical screws 3, when sealing ring 7 sealing performancies are bad, rely on conical screw 3, force upper gasket 10 to compress sealing ring 7 downwards, strengthen the sealing of inner layer sleeve 15 and slip spider 4.At two through holes of slip spider 4 lower side symmetrical distribution, comprise lead screw 5-a, hinge 5-b, the wedge shape hinge type clamping body 5 that slips sheet 5-c forms penetrates wherein.When dismounting connected epimerite 12, turn lead screw 5-a made four circular arc wedge-shaped card tile 5-c along its track chucking inner layer sleeve 15, made it can not be with commentaries on classics.The material of slips sheet 5-c is the 45# steel, and its tooth is after hard surfacing, and hardness is HRC40-45.Slip spider 4 has puts pressure hole 8, and its function is the pressure of regulating between surface pipe 6 and the inner layer sleeve 15.

Claims (2)

1, a kind of sealing device-step support formula casing head that is used between oil gas well well head surface pipe and the inner layer sleeve, comprise bearing plate 2, conical screw 3, slip spider 4, wedge shape hinge clamping body 5, sealing ring 7, lower gasket 9, upper gasket 10, technology backing plate 14, it is characterized in that: place a slip spider 4 on the described technology backing plate 14, in the through hole of two symmetries of slip spider 4 lower side, be placed with the wedge shape hinge clamping body of forming by screw 5-a, hinge 5-b, slips sheet 5-c 5 respectively, uniform three screwed holes of the upper side of slip spider 4.

2, device according to claim 1 is characterized in that:

The described slips sheet of A 5-c is the circular arc wedge-type shape.

The material of the described slips sheet of B 5-c is the 45# steel.

Tooth on the described slips sheet of the C 5-c is HRC40-45 through hard surfacing hardness.

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