CN2293641Y - Inner hole plug for maintaining wellhead device gate valve - Google Patents

Abstract

The utility model belongs to a gate valve maintenance tool-inner hole plug for a wellhead device of an oil and gas field. The plug includes fixing head with flange, casing, propelling screw pair, expanding ring type plug head and its control rod, pressure testing and releasing mechanism, and it uses the inlet port channel of the gate valve as the blocking point, and after being blocked, the gate valve may be maintained without need of killing well and stopping production. Not only saves financial resources and material resources, shortens the maintenance time, but also avoids sequelae of well killing maintenance and the like. Therefore, the device has the characteristics of simple structure, convenient use, safety, reliability, low construction cost, short time, maintenance without stopping production and the like.

Description

Wellhead assembly gate valve maintenance endoporus blanking plug

The utility model belongs to oil (gas) field oil recovery (gas) wellhead assembly duty maintenance gate valve endoporus blanking plug, also can be used for the maintenance that underground water is gathered gate valve in the wellhead assembly.

Oil (gas) field (gas) wellhead assembly that recovers the oil, it is the master switch of oil recovery (gas) well well head, it is by tubing head, little four-way and some gate valves are formed, wherein be in 1,2, No. 3 valve on the tubing head of key position if leakage is arranged, no matter be that spool, valve gap or joint ring leak, all can make whole well head be in no-console condition.Heavy then cause the well head accident, prestige association well site and personal safety gently then cause subterranean resource waste, contaminated environment.Because wellhead assembly is the collection (switching) that directly control is in high-pressure state and interior oil (gas), promptly in running order after installing, thereby keep in repair, handle very difficult, someone once imagined respectively processed one group of maintenance process screw thread in advance in tubing head side mouth, in order to maintenance, use when changing valve.Promptly in maintenance, adopt special tool that a kind of obstructions delivered to this screw thread from the gate valve endoporus when changing valve, screw that (the stream body carries out maintenance process again to block oil.The disadvantage of this kind method is: preprocessing maintenance process screw thread in tubing head side mouth, its diameter of thread must be less than the gate valve diameter of bore, thereby form a thin neck structure in passage, the age of a draught animal is fragile and ineffective under the effect that also the inner high voltage fluid constantly washes away; Sand in this outer fluid and other impurity also easily are deposited on screw thread in the age of a draught animal, corrode screw thread and make it ineffective when maintenance, thereby this kind method is unreasonable owing to the maintenance process screw thread is provided with the position, stop up the bad solution of process mesohigh sealing problem in addition, and the maintenance dependability is poor, thereby cannot apply always.And the general at present method that adopts is pressure and changes valve, maintenance, promptly changes and injects mud earlier in well before valve keeps in repair, and makes mud column pressure be slightly larger than OIH (gas) pressure, changes valve again after waiting to keep stablizing; Tubing flow displacement then, resume production.Should employ by the construction of this method and to put human and material resources greatly, must stop production again and carry out; And owing to mud impurity in the construction stops up formation pore, often to reduce after the kill-job, the high yield step-down is produced, even cause stripper well to become dried-up well by (gas) output.Thereby this method exists investment big, long and easy oil, the disadvantages such as the output of gas well of reducing of maintenance interval.

The objective of the invention is to design a kind of blocking device simple in structure, reliable, easy to use, this device can be kept under the situation that continues to produce at well head, stops up oil-feed, the gas passage of waiting to keep in repair gate valve, and gate valve is carried out maintenance process.With the efficient that improves maintenance wellhead assembly gate valve and safety, reliability, reach maintenance, change that gate valve does not stop production and safety, convenience, reliably, the wasting of resources and the environment pollution of minimizing maintenance sites are keeped in repair purposes such as existing disadvantage thereby overcome kill-job.

Solution of the present utility model is to select to wait to keep in repair the fluid inlet stomidium road of gate valve as stopping up point, blanking plug is fixed on the flange of this gate valve port of export by bolt, joint ring, then with the obstruction head on the blanking plug after valve outlet stomidium road, spool are sent into valve body entrance point duct, by the packing that stops up on the head this channel seal is stopped up again, after this just can be carried out maintenance process (comprise and change valve gap, flashboard, joint ring etc.) this valve.After maintenance finished, the packing that will stop up earlier on the head unclamped, and plug is retreated in the valve outlet stomidium road, and closing gate valve unloads blanking plug after pressure testing is qualified, load onto blind flange or afterwards valve just can recover operate as normal.Therefore, the utility model comprises obstruction head and propulsive mechanism thereof, and key is that its obstruction head is a packing formula sealing obstruction head; Propulsive mechanism is the thread bush of augering screw and band handwheel thereof; Blanking plug housing after this blanking plug also comprises a fixing body of a flanged dish and is positioned at this body tail, and the packing control lever of being located at the band packing pressure head of augering screw inner chamber; Packing is located between the packing pressure head and augering screw end of control lever head; Flexibly connect by screw thread between packing control lever and the augering screw inner chamber; The augering screw front portion is connected with a fixing intracoelomic cavity with flat key by the keyway on the sealing ring and the body of rod, and inner walls then is fixed in versatilely by thread bush and bearing and pressure ring thereof in the rear portion.For the ease of in the pressure testing that will stop up after the obstruction after the back of head overbottom pressure releases and keeps in repair, in a fixing body of blanking plug, also be provided with pressure release, pressure testing oil, air flue, also be provided with the needle-valve of a pressure meter and band relief hole on fixing head, this pressure meter and needle-valve and pressure release, pressure testing are tightly connected and are integral with oil, air flue.Between packing pressure head and augering screw end and packing, and the gasket ring that is equipped with a band conical surface between packing and the packing, the tapering of its conical surface generally is advisable with 5 °～10 °.

The utility model is owing to adopt the packing formula to stop up head, and will stop up and a little be selected in the high-pressure fluid entrance point, wait to repair on the flange of the gate valve port of export and the sealing of whole blanking plug is anchored on, thereby realized that maintenance wellhead assembly gate valve, replacing valve gap, flashboard, joint ring etc. do not need kill-job, do not stop production, financial resources had both been saved, material resources have shortened maintenance time greatly.Adopt this its operating expenses of blanking plug maintenance wellhead assembly gate valve generally to change 1/10th of valve, also can not cause sequelae such as environment pollution and obstruction down-hole formation hole less than kill-job.Therefore, the utlity model has simple in structurely, easy to use, safe and reliable property height is used to keep in repair short and non-environmental-pollution of well head gate valve operating expenses time low, that return to normal production and stops up the characteristics such as sequelae of down-hole formation hole.

Accompanying drawing and description of drawings

When Fig. 1 uses for the utility model structure and maintenance with wait to repair gate valve annexation schematic diagram (double dot dash line is gate valve to be repaiied among the figure);

Fig. 2 be the utility model site operation and when construction respectively with wellhead assembly in 1,2, No. 3 gate valve correlation schematic diagram.

Among the figure: 1, the blanking plug housing, 2, blanking plug is fixed a body, 3, fixing head flange dish, 4, sealing ring, 5, joint ring, 6, stop up head, 7, gate valve to be repaiied, 8, the packing pressure head, 9, gasket ring, 10, packing, 11, (pressure release, pressure testing) oil, air flue, 12, connector, 13, needle-valve, 14, the pressure release bolt, 15, pressure meter, 16, flat key, 17, lock-screw, 18, bearing, 19, bearing pressure ring, 20, handwheel, 21, thread bush, 22, lock nut, 23, augering screw, 24 packing control levers, 25, tubing head, 26～28: be respectively 1,2, No. 3 gate valves, 29, blanking plug.

Embodiment

Present embodiment is with maintenance

The time, 35～60MPa wellhead assembly flashboard is an example: blanking plug housing 1, and external diameter  176mm, middle part internal diameter  136mm, the two ends internal thread is M145 * 3mm, front end and the fixing long 60mm of a body 2 mating parts, rear portion and the long 38mm of bearing pressure ring mating part; Bearing 18 adopts two dish thrust ball bearings, and model is 8218; Thread bush 21, cover body diameter  90mm, middle front part boss external diameter  132mm, wide 20mm, internal thread are T60 * 8-2 left hand thread, and afterbody and handwheel 20 points of attachment are positive 6 side's bodies, and the back is by lock nut 22 lockings on the handwheel sleeve; A fixing body 2 front end flange dishes 3 advance with corresponding gate valve, and outlet(discharge) flange dish external diameter is identical with bolt hole size and position; Oil (gas) road 11 section diameters of offering on this body flange 3 perpendicular to axial direction are  6mm, and the bottom direct-axis is  3mm to part; The seat hole of connector 12 is M20 * 1.5, dark 22mm; Needle-valve 13 is for carrying the needle-valve of relief hole, and model is KQ600; Sealing ring 4, present embodiment adopt three groups of sealing rings, and the termination is 2 polytetrafluoroethylene V-type circle lap seal, and model is:  77 * 60 * 8mm, and compress by threaded pressure ring; O type rubber ring is all adopted for two groups in the back, and model is  72 * 5.8mm; Blanking plug and wait to repair the joint ring adopted between the gate valve 75 and be the concentric reducer steel loop, model is  110 * 88.7mm, axial high 22mm, two collar extensions add the glue ring of  110mm and  88.7mm respectively during installation.Augering screw 23 is the hollow loop bar of band internal and external screw thread, and length overall 690mm holds external diameter  62mm greatly, and the male thread portion direct-axis is to also being provided with a guiding keyway, the long 388mm of keyway; The present embodiment internal and external screw thread all adopts trapezoidal thread, and external screw thread is T60 * 8-2, and left-handed long 380mm, internal thread are T27 * 3-2, long 50mm, and external screw thread cooperates with thread bush 21, and internal thread then cooperates with packing control lever 24; Flat key 16 adopts the Type B flat key; Packing control lever 24 length overall 830mm, with the long 150mm of augering screw 23 mating part screw threads, screw thread also is T27 * 3-2; Left end packing pressure head 8 external diameter  62mm, its end face diameter  58mm; Stop up 6 and is made up of metal gasket ring group 9 and packing group 10, present embodiment adopts 3 road packings and 4 gasket rings is set at interval, packing employing butyronitrile rubber circle, and thick 14mm, external diameter  46mm, ring body shaft section are for trapezoidal, and the inclined-plane tapering is 9 °; Metal gasket ring 9 external diameter  62mm, the ring body shaft section is a trapezoid, the thick 7mm of annular inner portion, the thick 4.5mm of peripheral edge portion.

During use, at first will wait to repair the closing gate of gate valve 7, take off gate valve port of export blind flange or back level valve body, and load onto this blanking plug as shown in Figure 1 and it is anchored on the flange of gate valve 7 by bolt.Rotate handwheel 20 then augering screw 23 is axially sent in the valve outlet, stop up 6 thereupon prior to entering (this moment, packing was in relaxation state) in the valve outlet passage; Again brake gate door is opened, be rotated further handwheel 20, after driving augering screw 23 plug 6 being passed spool and sends in the valve body intake channel, rotate packing control lever 24, drive packing pressure head 8 moves right and pushes packings 10 by gasket ring 9, make it expanded radially, the sealing of valve body intake channel is stopped up, block the high-pressure fluid of down-hole.After this, open needle-valve 13, the overbottom pressure that will stop up in the 6 rear portion valve body by its relief hole releases (also can check simultaneously and stop up effect), just can carry out maintenance process to gate valve.After maintenance process is finished, the pressure testing on force (forcing) pump and the needle-valve 13, relief hole are connected pressure testing under a little more than well press strip spare; After pressure testing is qualified, backward rotation handwheel 20 will stop up head and retreat to the gate valve exit passageway, and the closing gate valve valve is to the whole valve body pressure testing, can take off blanking plug after qualified, and first-class blind flange or back one-level valve body can return to normal production.

Claims (3)

1, the endoporus blanking plug is used in a kind of wellhead assembly gate valve maintenance, comprises and stops up head and propulsive mechanism thereof; The obstruction head that it is characterized in that this blanking plug stops up head for the sealing of packing formula; Propulsive mechanism is the thread bush of augering screw and band handwheel thereof, the blanking plug housing after this blanking plug also comprises a fixing body of a flanged dish and is positioned at this body tail, and the packing control lever of being located at the band packing pressure head of augering screw inner chamber; Packing is located between the packing pressure head and augering screw end of control lever head; Flexibly connect by screw thread between packing control lever and the augering screw inner chamber; The augering screw front portion is connected with a fixing intracoelomic cavity with flat key by the keyway on the sealing ring and the body of rod, and inner walls then is fixed in versatilely by thread bush and bearing and pressure ring thereof in the rear portion.

2, by the described wellhead assembly gate valve maintenance of claim 1 endoporus blanking plug, it is characterized in that in a fixing body of this blanking plug, also being provided with pressure release, pressure testing oil, air flue, also be provided with the needle-valve of a pressure meter and band relief hole on a fixing body, this pressure meter and needle-valve and pressure release, pressure testing are tightly connected and are integral with oil, air flue.

3, by the described wellhead assembly gate valve maintenance of claim 1 endoporus blanking plug, it is characterized in that between packing pressure head and augering screw end and the packing, and the gasket ring that is equipped with a band conical surface between packing and the packing, the tapering of its conical surface generally is advisable with 5 °～10 °.

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