US2278050A - Well head closure - Google Patents

Description

H. ALLEN ET AL WELL HEAD CLOSURE 3 Sheets-Sheet 1 Filed June 7, 1938 3 2 mm m S QM mm w 6 mw m 5 ms mu nn m on r m on L QM .I I Q 3 IHNP mm QM MM on H m m a @m 3 F HERBERT ALLEN ED.L.LOREHN. I ENTORS TTORNEYS.

March 31, H ALLEN ET AL WELL HEAD CLOSURE s Shets-Sheet 2 Filed June '7, 1938 HERBERT ALLEN ED.L.LOREHN.

A TTORN E Y5.

March 31, 1942. H. ALLEN ET AL WELL HEAD CLOSURE 3 Sheets-Sheet 5 Filed June 7, 1938 HERBERT ALLEN ED.\ oREHN Patented Mar.3 1,1942

WELL HEAD CLOSURE I Herbert Allen and Edmond L. Lorehn, Houston,

Tex., assignors to Cameron Iron Works, a corporation or Texas Application June '1, 1938, Serial No. 212,242

Claims.

The invention relates to a well head closure device which is particularly adapted to maintain a seal while some member, such as a string of pipe or other device, is moved longitudinally in the well bore.

In many wells the drilling or producing operation must be carried on while the pressure in the well is confined. The movement of pipe sections which are connected together by couplings is diiilcult because of the enlarged diameter of the coupling. The present invention directs itself to the provision of a device which will maintain a seal with the well head and about a member movable in the well bore while permitting the passage of couplings or other enlargements upon the member being moved.

Another object of the invention is to provide a resilient sealing body for well closure devices wherein a pressure applied thereto will be distributed uniformly throughout the member to obtain a uniform sealing action.

Another object of the invention is to'provide a resilent sealing member with a curved surface which will be deformed by engagement against the part with which a seal is being effected so as to cause displacement of the sealing material.

A still further object of the 'inventionis to provide a pair of resilient sealing members which will interfit with each other and about an object a blowout preventer ram which will have a pre-' dominant pressure from the well bore tending to move it to closed position.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawings wherein:

Fig. l is aside elevation with certain parts in section and showing the ram members in open position.

Fig. 2 is a similar side elevation with the memhers closed about a string of pipe and illustrating a pipe coupling as passing through the sealing members.

Fig. 3 is a section taken on the line 3-3 of Fig. 1 and looking at the contact ng fac of the ram member.

body portion 3; which has the vertical passage 4 therethrough which is to be positioned in alignment with the well bore. Suitable openings 5 will receive attaching bolts so that the housing may be aifixed to the casing head.

A transverse chamber '7 intersects the passage fland extends through the housing 3 on each side of the central passage. Particular attention is directed to the peculiar shape of this transverse chamber 1, as best seen in Fig. 3. Such configuration has been provided in order to accommodate a larger body of sealing material at the sides of the passage dso as to assist in maintaining a seal. It will be noted that the side wall 8 of the housing 3 bulged outwardly so as to provide a generally elliptical shape in cross section for the chamber 1. These bulged portions also tend to hold the resilient portion of the ram against vertical displacement.

The end of each chamber is enlarged to form a' piston chamber l0 and the ends of the housing 3 are closed by the end plates I I.

A suitable opening I2 is provided at the inner end of the chamber III to receive a pipe by which pressure may be applied to the inner end of the chamber to move the ram I3. A second opening I4 is provided at the outer end of the chamber to receive a pipe to apply pressure to effect closing of the ram l3. The pipes which are connected to these openings may or may not be connected to the well bore by means of the opening l6 seen in Fig. 3. It is preferable, however, that the pipe entering the opening l4 shall be connected to the well bore so that any pressure occurring in the well bore will also be available on the back side of the piston l5 and will tend to move the ram l3 to closed position. It should be noted that the area of the piston I5 is greater than, the forward end of the ram so that there would be an available differential pressure tending to close the ram. In this manner the ram would automatically move to closed position when the differential pressure exceeded'the frictional resistance necessary to move the ram.

The leithand side of Fig. 1 shows an opening II on the inner end or the chamber 10 and another opening l8 on the outer end thereof. Suitable connections may be made at these openings to apply steam, mud or other pressure to accommodate the ram |3. This pressure may be used either independently or simultaneously with the well pressure which may be applied to the openings I2 and I4. The ram l3 includes the body portion which is in the nature of a. spool having the enlarged piston |5 on one end and the outstanding flange 2| on the inner end. The rear of the body is threaded at "to receive the spindle 23 by which the ram may be moved inwardly by rotation of the spindle. The spindle has an enlargement 24 thereon to abut against an anti-friction bearing 25 which is carried in the end plate I l. A pressure backing 25 may be positioned about the spindle in the end plate to prevent leakage and in addition a stufling box 21 may also be provided about the spindle. The end plate is held upon the housing by the bolts 29.

v The resilient sealing member is in the form of a body of rubber or other suitablematerial and is best seen in perspective in Fig. 5. This body is substantially elliptical in-cross section so as to fit within the chamber I. The main portion of the body is generally cylindrical on each side thereof, as seen in Fig. 4. g

The rear' of this body is provided with a plurality of recesses 33 which extend into the body a substantial distance as seen in the section of Fig. 1. These recesses are provided so that when pressure is applied to the face 34 of the body it will be capable of yielding under such pressure. These recesses 33 may be filled with cork or other compressible substance or particles of cork may be distributed in the body of rubber so as to afford an elasticityto feed the rubber forward in event of wear and to maintain a seal.

A plurality of openings 35 are arranged to receive the attaching bolts36 by which this resilient body is held upon the flange 2| of the ram l3.

In order to suitably reenforce the body 30 a frame 40 has been provided and is seen in perspective in Fig. 6.. This frame includes a base 4| which carries the openings 42 through which the bolts 36 are arranged to pass. This frame, as seen in Fig 1, is spaced from the flange 2| by the rear portion of the body 30 and the body movement of the ram member to force the removed to the elevation of the sealing member the 30 is molded therein so that the frame is fioating with the body and is movable relative to the flange 2|. It should be noted that the bolts 36 are slidable in the flange 2| so that when the resilient material is compressed the frame may move toward the flange 3| as seen in Fig. 2.

This frame is of peculiar construction because of the configuration of the body 30. On opposite corners of the frame are forwardly extending fingers 44 which extend forwardly in the body to reenforce the ears 55 thereon. On the opposite corners these arms are of lesser length so that they will not interfere with the movement of the ram. It should be noted that the top 45 and the bottom 46 are cut away at the sides to leave an open area which is spanned by the post 41. v a

As above noted the body 30 is molded upon the frame so that it may be fixed to the flange 2| by the bolts 36.

The forward face 34 of the ram body is curved at 50 on a vertical arc, as seen in Fig. 1. Thus when the body is moved toward a pipe such as 5| in Fig. 2 the central portion of the arc 50 will be the first to contact the pipe. Continued rubber of the sealing member will not be pulled along with the coupling because the coupling will engage this curved portion 52 and will thus move into the central part of the sealing member, as shown in Fig. 2.

The top and bottom of this are 50 are also cut away at the sides as at 54 so that when the two resilient sealing members are moved into engagement they will cooperate together-to form a beveled socket at both the top and the bottom of the seal.

In order that the sealing members will form a positive seal at the sides of the housing the lobe portions 3| have been provided to furnish an abundance of resilient material and on the forward faces these lobes are cut away to provide the ears 55. Each body portion has two of these ears on opposite corners, and the ears are arranged to be complementary to the corresponding ear on the opposite sealing member. Each ear has an inclined face 51 which is arranged to slide into contact with the similarly inclined face 51 on the opposite ram, so as to form a transverse seal and each ram has a forwardly inclined face 58 which will cooperate with a similar face 59 on the body of each ram at the base of the car. It seems obvious that these ears will interfit with each other as seen from the construction in Fig. 5.

Each of the cars is provided with a recess 59 in order to provide resiliency and there are also openings 60 in the body which extend to the forward portion thereof.

In actual operation as the members are moved to closed position the ears will interfit with each other and be forced firmly into engagement.

The inclined faces 51, 58 and 59 will abut with each other and as continued movement of the rams is had then these parts will tend to apply a pressure to each other and this pressure will be distributed uniformly throughout both of the resilient bodies 30. Of course, the arc face 50 will be pressed about the pipe 5| to maintain a seal. The periphery of the body 30 and the lobes 3| will be pressed against the inside faces of the chamber 1 of the housing 3 and in every direction the pressurewill be uniform due to the resilient nature of the body 30.

If the pipe 5| is moved in the well bore if a coupling or other enlargement 53 arrives at the elevation of the sealing members it will be guided into the sealing members by the inclined faces 52 and 54 and will cause additional compression of the resi-ient body 30. This additional compression is possible due to the provision of the recesses 33 and, as seen in Fig. 2, these recesses have become constricted due to this additional pressure caused by the enlargement 53.

When the blowout preventer orstripper is positioned on the well bore and the pipe in the opening l4 connected to the well bore, then any pressure occurring in the well bore will be available in the chamber l0 behind the piston l5. The size of this piston will be so designed that if a pressure above a predetermined amount occurs in the well bore then the differential pressure will automatically close the ram and the greater the pressure in the well bore the greater will be the tendency of the ram member to form a seal.

If it is desired to move the ram by other pressure it may be applied through the opening I8 or the ram may be closed manually by manipulation of the spindle 23.

Where the ram is merely held in closed position by the differential pressure in the well the whole ram member may yield when a coupling is to be passed. On the other hand, the ram can be locked in closed position by manipulation of the spindle 23.-

Broadly the invention contemplates a stripper or blowout preventer for well heads wherein the closure may be accomplished automatically or mechanically and wherein an abundance of sealing material is provided at the sides of the closure in order to maintain a seal and further wherein a uniform pressure is applied to all of the parts due to the resiliency of the sealing body.

What is claimed is:

1. A ram construction for well strippers comprising a metal skeleton frame, a body of resilient material molded into and about said frame, said resilient material including a lobe portion at each side of the frame, each of said lobe portions having a forwardly extending ear, the body of material being recessed and convexly contoured between said ears.

2. A resilient ram member for stripper heads including a metal skeleton having upper and lower portions, struts connecting said portions, a pair of outward projections from the ends of a diagonal across the front of the skeleton, and a body of resilient material carried by said skeleton and having outwardly extending ears encasing said projections.

3. A resilient ram member for stripper heads including a metal skeleton having upper and lower portions, struts connecting said portions, a pair of outward projections disposed on the ends of a diagonal across the front of the skeleton, and a body of resilient material carried by said skeleton and enclosing said projections said body having a convexly curved surface intermediate said projections. g

4. A stripper head for wells including a housing, lateral chambers therein, said chambers being substantially circular in cross section with a lobe portion at each side thereof, a ram in each chamber, a resilient sealing member on each ram of a configuration to fit and slide in said chamher, a recessed surface on the front face of said member, between said lobes so that an increased body of resilient material is provided by said lobes.

5. A stripper head for wells comprising a body having a through passage and opposed chambers laterally thereof, each of said chambers communicating with said passage and comprising a substantially circular central portion and a lobular enlargement at each side thereof, opposed rams movably fitting in said chambers, each of said rams including a pair of complementary ears projecting forwardly from the lo-bular portion of the ram so that the opposed ears move into interfitting relation and form a substantially circular opening within said passage, and means for moving said rams toward and from each other.

HERBERT ALLEN. EDMOND L. LOREHIN.

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