US3335987A - Adjustable oil well mast support - Google Patents
Adjustable oil well mast support Download PDFInfo
- Publication number
- US3335987A US3335987A US569339A US56933966A US3335987A US 3335987 A US3335987 A US 3335987A US 569339 A US569339 A US 569339A US 56933966 A US56933966 A US 56933966A US 3335987 A US3335987 A US 3335987A
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- substructure
- shoes
- shoe
- mast
- oil well
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- 239000003129 oil well Substances 0.000 title claims description 16
- 238000004873 anchoring Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 241000722946 Acanthocybium solandri Species 0.000 description 1
- 102000010029 Homer Scaffolding Proteins Human genes 0.000 description 1
- 108010077223 Homer Scaffolding Proteins Proteins 0.000 description 1
- 241000364021 Tulsa Species 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B15/00—Supports for the drilling machine, e.g. derricks or masts
Definitions
- This invention relates to supports for oil well masts, and more particularly to supports that can be adjusted to keep the masts level.
- masts Although only masts will be referred to herein, it is to be understood that this term is used in a broad sense to cover standard derricks as well.
- the foundation, base or substructure on which the mast rests sometimes settles unevenly so that the mast no longer is plumb over the Well. Due to the great weight of the entire rig, which may be as much as 400,000 pounds, it is very difficult to correct the situation by jacking up the low corner or side. It therefore has been the practice to adjust the mast only, because of-course it weighs only a fraction of the complete rig.
- shims are placed under the raised mast shoes and then the shoe anchor bolts are tightened again.
- FIG. 1 is a plan view of a substructure
- FIG. 2 is a side view thereof
- FIG. 3 is an enlarged plan view of a front shoe
- FIG. 4 is a vertical section taken on the line IVIV of FIG. 3;
- FIG. 5 is a horizontal section taken on the line V-V of FIG. 4;
- FIG. 6 is an enlarged plan view of a rear shoe
- FIG. 7 is a vertical section taken on the line VIIVII of FIG. 6;
- FIG. 8 is a horizontal section taken on the line VIII- VIII of FIG. 7;
- FIG. 9 is a side view, partly in section, of a modification.
- FIGS. 1 and 2 of the drawings a typical substructure 1 is shown, on which there are shoes 2 and 3 for the front feet of the mast stem 4 and the front and back feet of the mast gin pole 5.
- shoes 2 and 3 for the front feet of the mast stem 4 and the front and back feet of the mast gin pole 5.
- all of the shoes are firmly anchored to the substructure by means of anchor bolts 6 and 7.
- the base of each shoe rests on top of a vertical stem 8 in the form of a heavy reinforced short length of pipe. As shown in FIG.
- the stern extends down into a vertical passage in the substructure and is supported therein by its upper end, which extends radially outward like a flange to form a head 9.
- the passage that receives it may be formed by a piar of vertically spaced aligned openings 10 and 11 in parallel plates.
- the upper plate 12 rests on top of a pair of horizontal beams 13 3,335,987 Patented Aug. 15, 1967 forming part of the top of the substructure and is welded to them.
- the lower plate 14 is seated in recesses 15 in a pair of parallel vertical cross plates 16, the ends of which are welded to the adjoining beams.
- the shims may take various forms, but they should be bifurcated so that they can be inserted beneath the shoe astraddle of the stem as shown in FIGS. 3 and 5.
- the side of each shim opposite its open side preferably is provided with a projection having a notch 21 in it for receiving one of the anchor bolts that generally is removed before the shims are inserted beneath the shoes.
- that bolt can be left in place until after all of the shims have been installed, whereupon it can be removed, the shims all rotated to align their notches with the empty bolt holes, and then the missing bolt replaced. This locks the shims in place so that they cannot move away from the stern.
- a raised shoe will be free to remain in alignment with the mast leg as the shoe is raised so that no strain will be put on the connection between the mast and shoe. This is accomplished by making the head 9 of the stem spherical as shown in FIG. 4 and providing the bottom of the shoe with a spherical recess 23 that receives the head. This ball and socket type connection therefore allows the shoe to tilt in any direction on the stem as required in order to maintain alignment.
- a tilted shoe will not be parallel to the top of the substructure, it is desirable to provide the top of the shoe plate around each bolt hole with a spherical recess 25, in which a spherical washer 26 on the anchor bolt is seated.
- the bottom of the supporting plate 12 is provided with a spherical recess 27 around each bolt hole for receiving a spherical washer 28 supported by the head of the bolt beneath it.
- each shoe 3 is seated on the spherical head 30 of a vertical stem 31 that is adjustable vertically in plates 32 and 33 supported by a pair of horizontal beams 34 forming part of the top of the substructure.
- the shoes can be shimmed up, as indicated in FIG. 2, by shims 35 like front shims 20.
- the upper end of the stem 40 is rigidly secured to the shoe 41.
- the substructure passage formed by the opening 42 through plate 43 must be oversize to permit the stem that it receives to tilt in it when it is necessary for the shoe to be tilted relative to the substructure 44 in order to stay in line with the derrick leg connected to it.
- Plate 43 is Welded to the substructure.
- the shims 46 that are placed between the shoe and the substructure to hold the shoe in a raised position remain parallel to the bottom of the shoe plate because they rest on a washer 47 that encircles the stem and has a spherical bottom seated in a spherical recess 48 around the opening through the substructure plate 43. It will be seen that this washer will tilt with the shoe and therefore remain parallel to it.
- the anchor bolts 49 can be supplemented or even dispensed with by providing the stem 40 with a screw thread and screwing a large retaining nut 50 onto it up against the bottom of plate 43.
- the top of the nut should be spherical in order to engage the plate around the stern even though the stem is tilted. It is not always necessary that the stem be capable of tilting, because a self-aligning connection between the foot of the derrick and the shoe can be employed to allow a change in alignment of the shoe and derrick.
- An adjustable oil well mast support comprising a substructure, shoes on the substructure for the feet of a mast, a central stern extending down from the bottom of each shoe, the substructure being provided with vertical passages slidably receiving the stems, means holding the shoes in place, said stems being elevatable in said passages to raise the shoes above the substructure after said means have been loosened, whereby shims can be placed between the shoes and the substructure to support the raised shoes.
- An adjustable oil well mast support according to claim 1, including bifurcated shims straddling at least one of said stems between the shoe thereon and the substructure.
- An adjustable oil Well mast support according to claim 4, in which said holding means are bolts anchoring the shoes to the substructure, and the shims on a stem are provided with notches receiving at least one of said boits to help hold the shims in place.
- each of said stems has a spherical head
- the bottom of each shoe is provided with a spherical recess receiving the underlying stem head to permit the shoe to be tilted on the stem
- said holding means are bolts anchoring the shoes to the sub structure.
- each of said passages is formed from a plurality of vertically spaced members provided with aligned openings therethrough receiving a stem to keep it from tilting.
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- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
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Description
g 15, 1957 H. J. WOOLSLAYER ETAL 3,335,987
ADJUSTABLE OIL WELL MAST SUPPORT Filed Aug. 1, 1966 4 Sheets-Sheet 1 Fig 2 INVENTORS. HOME/P J. WOOLSL/i YER (EC/L JE/V/(l/VS ATTORNE V6 Aug. 15, 1967 H. J. WOOLSLAYER ETAL 3,335,937
ADJUSTABLE O IL WELL MAST SUPPORT 4 Sheets-Sheet 2 Filed Aug. 1, 1966 YER ATTOR/Vl-VS IN \"ENTORS. HOME? J. 14/001544 B Y (EC/L JEN/(0V5 TE m Y LWM m w //K \m i w A u K T 1111 TE 6 1967 H. J. WOOLSLAYER ETAL 3,335,987
ADJUSTABLEOIL WE'LL MAST SUPPORT Filed Aug. 1, 1966 4 Sheets-Sheet a INVENTURS. HOMER J. WOOLSZAYER (EC/L JEN/(INS AQTTORNEVS.
g- 1957 H. J. WOOLSLAYER ETAL 3,335,987
ADJUSTABLE OIL WELL MAST SUPPORT 4 Sheets-Sheet 4 Filed Aug. 1, 1966 YER INVENTORS. WOOLSLA HOME/Q J.
ATTOR/VEKS.
United States Patent 3,335,987 ADJUSTABLE OIL WELL MAST SUPPORT Homer 3. Woolslayer and Cecil Jenkins, Tulsa, Okla., as-
signors to Lee C. Moore Corporation, a corporation of Pennsylvania Filed Aug. 1, 1966, Ser. No. 569,339 8 Claims. (Cl. 248-23) This invention relates to supports for oil well masts, and more particularly to supports that can be adjusted to keep the masts level.
Although only masts will be referred to herein, it is to be understood that this term is used in a broad sense to cover standard derricks as well. During the drilling of oil wells, the foundation, base or substructure on which the mast rests sometimes settles unevenly so that the mast no longer is plumb over the Well. Due to the great weight of the entire rig, which may be as much as 400,000 pounds, it is very difficult to correct the situation by jacking up the low corner or side. It therefore has been the practice to adjust the mast only, because of-course it weighs only a fraction of the complete rig. When the low side of the mast is raised to level it, shims are placed under the raised mast shoes and then the shoe anchor bolts are tightened again.
In order to provide satisfactory stability, large shims have been required, which weigh several thousand pounds. Another objection to them is that they have made it diflicult to maintain proper alignment of the mast foot, due to the extended length of the shoe anchor bolts.
It is among the objects of this invention to provide an adjustable oil well mast support which requires only small and relatively light-weight shims when a shoe is raised to level the mast, which maintains proper alignment of the raised mast foot, and on which the mast remains stable.
The invention is illustrated in the accompanying drawings, in which:
FIG. 1 is a plan view of a substructure;
FIG. 2 is a side view thereof;
FIG. 3 is an enlarged plan view of a front shoe;
FIG. 4 is a vertical section taken on the line IVIV of FIG. 3;
FIG. 5 is a horizontal section taken on the line V-V of FIG. 4;
FIG. 6 is an enlarged plan view of a rear shoe;
FIG. 7 is a vertical section taken on the line VIIVII of FIG. 6;
FIG. 8 is a horizontal section taken on the line VIII- VIII of FIG. 7; and
FIG. 9 is a side view, partly in section, of a modification.
Referring to FIGS. 1 and 2 of the drawings, a typical substructure 1 is shown, on which there are shoes 2 and 3 for the front feet of the mast stem 4 and the front and back feet of the mast gin pole 5. Originally, all of the shoes are firmly anchored to the substructure by means of anchor bolts 6 and 7. However, provision is made for raising any one or more of the shoes in case the substructure settles and throws the mast out of line with the well. To permit the front shoes to be raised and shimmed up, the base of each shoe rests on top of a vertical stem 8 in the form of a heavy reinforced short length of pipe. As shown in FIG. 4, the stern extends down into a vertical passage in the substructure and is supported therein by its upper end, which extends radially outward like a flange to form a head 9. To prevent the stem from tilting in the substructure, the passage that receives it may be formed by a piar of vertically spaced aligned openings 10 and 11 in parallel plates. The upper plate 12 rests on top of a pair of horizontal beams 13 3,335,987 Patented Aug. 15, 1967 forming part of the top of the substructure and is welded to them. The lower plate 14 is seated in recesses 15 in a pair of parallel vertical cross plates 16, the ends of which are welded to the adjoining beams.
If it becomes desirable to raise one of the front shoes as indicated in FIG. 2, the nuts on its long anchor bolts 6 are loosened the necessary amount or, in case the bolts are short they are removed and replaced by longer bolts. Then a jack (not shown) is placed beneath the stem and operated to jack up the stem and shoe and the mast and gin pole legs attached to it. When the shoe reaches the desired height where it is level with the other shoes, shims 20 are placed between the shoe and the substructure and then the nuts on the anchor bolts are tightened to hold the shoe firmly in place. 1
The shims may take various forms, but they should be bifurcated so that they can be inserted beneath the shoe astraddle of the stem as shown in FIGS. 3 and 5. As it is desirable to lock the shims in place by means of one of the anchor bolts, the side of each shim opposite its open side preferably is provided with a projection having a notch 21 in it for receiving one of the anchor bolts that generally is removed before the shims are inserted beneath the shoes. However, that bolt can be left in place until after all of the shims have been installed, whereupon it can be removed, the shims all rotated to align their notches with the empty bolt holes, and then the missing bolt replaced. This locks the shims in place so that they cannot move away from the stern.
Another feature of this invention is that a raised shoe will be free to remain in alignment with the mast leg as the shoe is raised so that no strain will be put on the connection between the mast and shoe. This is accomplished by making the head 9 of the stem spherical as shown in FIG. 4 and providing the bottom of the shoe with a spherical recess 23 that receives the head. This ball and socket type connection therefore allows the shoe to tilt in any direction on the stem as required in order to maintain alignment.
Since a tilted shoe will not be parallel to the top of the substructure, it is desirable to provide the top of the shoe plate around each bolt hole with a spherical recess 25, in which a spherical washer 26 on the anchor bolt is seated. Likewise, the bottom of the supporting plate 12 is provided with a spherical recess 27 around each bolt hole for receiving a spherical washer 28 supported by the head of the bolt beneath it. With this arrangement, there is no tendency to bend the bolts when the shoe is not parallel to the substructure.
The arrangement of the rear shoes 3 is similar to the front shoes, except the rear shoes are fastened rigidly to the lower ends of the gin pole rear legs 5. As shown in FIG. 7, each shoe 3 is seated on the spherical head 30 of a vertical stem 31 that is adjustable vertically in plates 32 and 33 supported by a pair of horizontal beams 34 forming part of the top of the substructure. The shoes can be shimmed up, as indicated in FIG. 2, by shims 35 like front shims 20.
The construction just described permits a shoe to be raised to a desired level and then be supported there by small light-weight shims in a manner that does not reduce the stability of the mast. At the same time, misalignment of the shoes and mast is prevented and undue strain is not put on the connection between them.
In the modification shown in FIG. 9, the upper end of the stem 40 is rigidly secured to the shoe 41. In View of this, the substructure passage formed by the opening 42 through plate 43 must be oversize to permit the stem that it receives to tilt in it when it is necessary for the shoe to be tilted relative to the substructure 44 in order to stay in line with the derrick leg connected to it. Plate 43 is Welded to the substructure. The shims 46 that are placed between the shoe and the substructure to hold the shoe in a raised position remain parallel to the bottom of the shoe plate because they rest on a washer 47 that encircles the stem and has a spherical bottom seated in a spherical recess 48 around the opening through the substructure plate 43. It will be seen that this washer will tilt with the shoe and therefore remain parallel to it.
With this construction, the anchor bolts 49 can be supplemented or even dispensed with by providing the stem 40 with a screw thread and screwing a large retaining nut 50 onto it up against the bottom of plate 43. In such a case, the top of the nut should be spherical in order to engage the plate around the stern even though the stem is tilted. It is not always necessary that the stem be capable of tilting, because a self-aligning connection between the foot of the derrick and the shoe can be employed to allow a change in alignment of the shoe and derrick.
According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.
We claim:
1. An adjustable oil well mast support comprising a substructure, shoes on the substructure for the feet of a mast, a central stern extending down from the bottom of each shoe, the substructure being provided with vertical passages slidably receiving the stems, means holding the shoes in place, said stems being elevatable in said passages to raise the shoes above the substructure after said means have been loosened, whereby shims can be placed between the shoes and the substructure to support the raised shoes.
2. An adjustable oil well mast support according to claim 1, in which said stems are rigidly connected to the shoes and are threaded, and said holding means are nuts screwed onto the stems.
3. An adjustable oil well mast support according to claim 1, in which said stems are rigidly connected to the shoes, said passages are large enough to permit said stems to be tilted therein, the substructure around the upper end of each passage is provided with a concave recess, and a spherical washer is slidably mounted on each stem and seats in the underlying recess.
4. An adjustable oil well mast support according to claim 1, including bifurcated shims straddling at least one of said stems between the shoe thereon and the substructure.
5. An adjustable oil Well mast support according to claim 4, in which said holding means are bolts anchoring the shoes to the substructure, and the shims on a stem are provided with notches receiving at least one of said boits to help hold the shims in place.
6. An adjustable oil well mast support according to claim 1, in which the upper end of each of said stems has a spherical head, the bottom of each shoe is provided with a spherical recess receiving the underlying stem head to permit the shoe to be tilted on the stem, and said holding means are bolts anchoring the shoes to the sub structure.
7. An adjustable oil well mast support according to claim 6, in which each of said passages is formed from a plurality of vertically spaced members provided with aligned openings therethrough receiving a stem to keep it from tilting.
8. An adjustable oil well mast support according to claim 6, including washers mounted on each bolt and having spherical inner surfaces seated in corresponding recesses in the shoes and substructure.
References Cited UNITED STATES PATENTS 596,280 12/1897 Short 24823 2,739,773 3/1956 Rougernont 248--13 3,021,100 2/1962 Verhota 248-23 3,235,206 2/1966 Luketa 248-23 JOHN PETO, Primary Examiner.
Claims (1)
1. AN ADJUSTABLE OIL WELL MAST SUPPORT COMPRISING A SUBSTRUCTURE, SHOES ON THE SUBSTRUCTURE FOR THE FEET OF A MAST, A CENTRAL STEM EXTENDING DOWN FROM THE BOTTOM OF EACH SHOE, THE SUBSTRUCTURE BEING PROVIDED WITH VERTICAL PASSAGES SLIDABLY RECEIVING THE STEMS, MEANS HOLDING THE SHOES IN PLACE, SAID STEMS BEING ELEVATABLE IN SAID PASSAGES TO RAISE THE SHOES ABOVE THE SUBSTRUCTURE AFTER SAID MEANS HAVE BEEN LOOSENED, WHEREBY SHIMS CAN BE PLACED BETWEEN THE SHOES AND THE SUBSTRUCTURE TO SUPPORT THE RAISED SHOES.
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US569339A US3335987A (en) | 1966-08-01 | 1966-08-01 | Adjustable oil well mast support |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US569339A US3335987A (en) | 1966-08-01 | 1966-08-01 | Adjustable oil well mast support |
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US3335987A true US3335987A (en) | 1967-08-15 |
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US569339A Expired - Lifetime US3335987A (en) | 1966-08-01 | 1966-08-01 | Adjustable oil well mast support |
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Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3452953A (en) * | 1967-09-22 | 1969-07-01 | Combustion Eng | Base leg connector |
US4108407A (en) * | 1975-07-14 | 1978-08-22 | Rca Corporation | Adjustment device |
US4784364A (en) * | 1987-09-17 | 1988-11-15 | Arrow Support Systems Corp. | Heat-barrier chock and sole plate system |
US5016338A (en) * | 1988-09-21 | 1991-05-21 | Rowan Jr Robert L | Method for adjusting the vertical position of a frame on a foundation |
US5110082A (en) * | 1988-09-21 | 1992-05-05 | Rowan Jr Robert L | Adjustable apparatus for supporting machinery or other load |
US20060108176A1 (en) * | 2003-02-26 | 2006-05-25 | Tomas Funes Gavilan | Safety equipment for building sites |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US596280A (en) * | 1897-12-28 | Foundation for g en erator-fram es | ||
US2739773A (en) * | 1952-02-13 | 1956-03-27 | Reed Prentice Corp | Self-adjusting support for machine tool beds |
US3021100A (en) * | 1960-09-02 | 1962-02-13 | Robert J Verhota | Support |
US3235206A (en) * | 1962-12-31 | 1966-02-15 | Frank J Luketa | Trawl winch mounting |
-
1966
- 1966-08-01 US US569339A patent/US3335987A/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US596280A (en) * | 1897-12-28 | Foundation for g en erator-fram es | ||
US2739773A (en) * | 1952-02-13 | 1956-03-27 | Reed Prentice Corp | Self-adjusting support for machine tool beds |
US3021100A (en) * | 1960-09-02 | 1962-02-13 | Robert J Verhota | Support |
US3235206A (en) * | 1962-12-31 | 1966-02-15 | Frank J Luketa | Trawl winch mounting |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3452953A (en) * | 1967-09-22 | 1969-07-01 | Combustion Eng | Base leg connector |
US4108407A (en) * | 1975-07-14 | 1978-08-22 | Rca Corporation | Adjustment device |
US4784364A (en) * | 1987-09-17 | 1988-11-15 | Arrow Support Systems Corp. | Heat-barrier chock and sole plate system |
US5016338A (en) * | 1988-09-21 | 1991-05-21 | Rowan Jr Robert L | Method for adjusting the vertical position of a frame on a foundation |
US5110082A (en) * | 1988-09-21 | 1992-05-05 | Rowan Jr Robert L | Adjustable apparatus for supporting machinery or other load |
US20060108176A1 (en) * | 2003-02-26 | 2006-05-25 | Tomas Funes Gavilan | Safety equipment for building sites |
US7273200B2 (en) * | 2003-02-26 | 2007-09-25 | Tomas Funes Gavilan | Safety equipment for building sites |
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