US3884519A - Safety latch for well pipe elevators - Google Patents
Safety latch for well pipe elevators Download PDFInfo
- Publication number
- US3884519A US3884519A US393085A US39308573A US3884519A US 3884519 A US3884519 A US 3884519A US 393085 A US393085 A US 393085A US 39308573 A US39308573 A US 39308573A US 3884519 A US3884519 A US 3884519A
- Authority
- US
- United States
- Prior art keywords
- latch
- door
- arm
- lever
- latch arm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000037431 insertion Effects 0.000 claims description 2
- 238000003780 insertion Methods 0.000 claims description 2
- 230000007246 mechanism Effects 0.000 description 10
- 210000000078 claw Anatomy 0.000 description 8
- 230000001052 transient effect Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 241000282693 Cercopithecidae Species 0.000 description 1
- 101100229963 Drosophila melanogaster grau gene Proteins 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 210000005069 ears Anatomy 0.000 description 1
- 239000004519 grease Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 230000009528 severe injury Effects 0.000 description 1
Images
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
- E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
- E21B19/02—Rod or cable suspensions
- E21B19/06—Elevators, i.e. rod- or tube-gripping devices
Definitions
- a well pipe elevator has hinged body parts allowing the elevator to be opened and closed, one of the body parts having a pivoted latch engageable with latch lugs on the other body part, the latch being spring loaded to a latching position, and said other of the body parts having an operating handle provided with a safety lock for holding the latch in a latching position.
- the operating handle is spring loaded to a latch locking position and is manually shiftable to release the lock and to cam the latch open.
- Well pipe elevators of the type here involved generally comprise a pair of hingedly interconnected body parts which cooperateto form a circular structure adapted to be applied to and removed from a well pipe, such as a well drilling pipe, to support the well pipe by the hoist equipment in the derrick.
- the elevator is opened and closed by workmen on the platform and on a monkey board in the derrick.
- latching and latch locking mechanisms have heretofore been provided, whereby, when the elevator body parts are closed and latched, a latch lock must be released before the latch can be opened.
- the latch and latch lock mechanisms have been incorporated in the structures requiring that the workmen utilize both hands in opening the elevator, but in some instances the elevator may be opened by one hand, the other hand in some instances being needed only to stabilize the elevator.
- Such latch and latch locking arrangements have heretofore been either complicated in construction, uncertain in use or difficult to manipulate.
- latch operating mechanism is accidentally operated upon contact with some structure. or equipment in the derrick, since the latch operating mechanisms are generally exposed.
- the present invention provides a simple well pipe elevator with a latch and latch locking mechanism combined with a latch operating mechanism, whereby the latch is positively held in a latched condition when the latch is closed, but the latch is opened easily by the operating member following release of the latch lock which is incorporated as a part of the operating member.
- the invention provides an elevator with a latch arm pivotally carried by one body part and adapted to latch with lugs formed on the companion body part, automatically upon closure of the elevator.
- the latch is opened by an operating member pivotally carried by the second mentioned body part, by a camming action which reduces the manual force required to overcome the latch closing spring.
- the latch operating member has integral therewith a latch lock which is automatically positioned relative to the latch to prevent the latch from opening, until such time as the operating member is purposely manipulated to open the latch.
- the latch and latch lockin'g arrangement is such that any tendency of the latch to open, which may be caused by vibrationor transient forces during use, causes the operating member to be held more forcefully in its latch locking position.
- the elevator and. the latch operating means are constructed and arranged so that the operating means is disposed close to the elevator body in a location protected against accidental contact with struc-' ture or equipment in the derrick.
- FIG. 1 is a top plan of a well pipe elevator shown in a closed condition and made in accordance with the invention
- FIG. 2 is a side elevation of the elevator of FIG. 1;
- FIG. 3 is a fragmentary top plan showing the latch released and the elevator partially opened
- FIG. 4 is an enlarged fragmentary side elevation of the safety latch mechanism as seen in FIG. 2;
- FIG. 5 is an enlarged fragmentary top plan showing the safety latch mechanism in a latched and locking condition
- FIG. 6 is a view corresponding to FIG. 5, but showing the safety latch mechanism in a latched but unlocked condition
- FIG. 7 is a view corresponding to FIGS. 5 and 6 but showing the latch released, just prior to opening of the elevator.
- the invention is incorporated in a well pipe elevator of the so-called side door type, wherein the elevator has a major body part 1 and a minor companion body part or door 2, hingedly interconnected together.
- the body part 1 has vertically spaced ears 3 between which a hinge portion 4 on the door 2 is disposed and pivotally or hingedly mounted on a pin 5.
- a grease fitting 6 is preferably provided to enable lubrication of the hinge connection.
- the body parts 1 and 2 cooperate to form a circular pipe opening 7 circumscribed by a shoulder 8 adapted to support a well pipe by engagement beneath a tool joint shoulder or upset on the pipe, as is well known.
- the body 1 has outstanding arms 9 and 10 spaced vertically to form openings 1 1 adapted to receive a pair of elevator links, which, as is also well known, are adapted to suspend the elevator from the usual hook, whereby the usual hoist mechanism raises and lowers the elevator in the derrick.
- Link blocks 12 are pivotally connected at 13 and bolted at 14 to the link arms 9 and 10 to removably retain the links in the openings 11.
- latch means L and latch operating and locking means 0 are provided for releasably latching and locking the door 7 2 in the closed position, as seen in FIGS. 1, 2, 4 and 5, the operating means 0 being operable to unlock the latch means L and actuate the same to the open position as seen in FIGS. 3 and 7, :so that the door 2 can be opened as seen in FIG. 3.
- the latch means L comprises a latch arm 15 having cars 16 which are straddled by upper and lower pairs of vertically spaced lugs 17, and the ear and lugs 16 and 17, respectively, receive a pivot pin 18, whereby the latch arm 15 is pivotally supported.
- a coiled torsion spring 19 is disposed about the pivot pin 18 and acts upon the latch arm 15 in a direction tending to close the latch means L, that is, in a counterclockwise direction.
- the spring 19 has one end 20 which abuts with the body 1, and another end 21 which abuts with a spring anchor lug 22 formed on the lever 15.
- the latch arm 15 has upwardly and downwardly projecting latch lugs 23 and 24, respectively, and a vertical web 25.
- latch lugs 23 and 24 cooperate with companion latch lugs 26 and 27 which project from the door 2 so as to be engaged by the latch lugs 22, 23 and 24, as best seen in FIGS. 1 and 4, so that the door is precluded from swinging open until the latch arm 15 is moved in a clockwise direction about the pivot 18.
- the lugs 26 and 27 have camming surfaces 28 engageable with arched confronting edge surfaces 29 on the latch lugs 23 and 24, so that when the door 2 is closed the companion surfaces 28 and 29 cam the latch arm 15 in a clockwise direction until the lugs 26 and 27 pass the latch lugs 23 and 24, at which time the spring 19 will bias the latch arm 15 to the latched position of FIGS. 1, 4 and 5.
- the operating means comprises a lever 30 having a handle 31.
- the lever 30 is pivotally mounted upon a hinge pin 32 which extends through vertically spaced horizontal flanges 33 on the door 2 which project outwardly from the door to provide a space 34 in which the lever 30 is recessed when the elevator is closed, so as to be protected from accidental operation by contact with equipment in the derrick.
- the lever 30 comprises a lever section 35 at one side of the pivot pin 32 and having at its free end the handle 31, whereby the lever may be actuated to overcome the normal bias of a coiled torsion spring 37 which is disposed about the pivot pin 32 and at one end engages a vertical side surface of the door 2 and at its other end engages a portion 36 on the lever 30.
- the lever section 35 is provided with means engageable with the latch arm to open the latch means I. in response to pivotal movement of the operating means 0 about the pivot pin 32 in a clockwise direction. More particularly, a roller 38 is rotatably mounted upon a pin 39 which extends vertically between a pair of spaced lugs 40 formed on the lever, the roller 38 being engageable with the web 25 of the latch arm 15, as seen in FIGS. 6 and 7, to progressively cam the latch arm 15 to the unlatched position of FIG. 7, from the latched position of FIG. 6.
- the operating means 0 includes latch locking means in the form of a claw 41 integral with the lever 30, and located at the other side of the pivot pin 32 from the handle 31, so that when the operating means 0 is actuated, the locking claw 41 is first moved to an unlocked position, before the latch 15 is opened.
- the claw 41 includes a recurved or hook-like free end 42 having an internal surface 42a which is adapted to confront an external surface 254 of the latch web 25, as seen in FIG.
- the operating means 0, the claw 41 and the web 25 of the latch arm 15, are arranged and constructed in such a way that the confronting surfaces 42a and 25a on the claw and on the web, respectively, are located at the opposite sides of the pivot 32 from the handle 31, whereby any force tending to inadvertently open the latch induces a counterclockwise force on the lever 30, thereby assisting the spring 37 in holding the lever 30 in the latch locking position, with an internal stop lug 30a of the lever 30 engaging a side wall of the door, as seen in FIG. 5.
- the operating means are shrouded or sheltered in the space 34 between the door flanges 33.
- a workman in the derrick or on the derrick floor need merely grip the handle 31 and pull outwardly thereon to initially release the latch lock claw 41, as seen in FIG. 6, before the roller 38 commences to cam the latch about its pivot pin 18 to the open position, as seen in FIG. 7, at which the respective latch lugs 23 and 24 are disengaged from the lugs 26 and 27 on the door 2.
- the door can then be pulled open to the position of FIG. 3.
- the camming surfaces 28 leading to the lugs 26 and 27 on the door 2 engage the latch lug surfaces 29 to pivot the latch arm 15 out of the way, as the lugs 26 and 27 pass inwardly to a position at which the latch arm can reengage with the door.
- the closing action obviously requires that the operating means 0 be activated from its normal position, as seen in FIG. 5, so that the claw 41 reengages the web 25.
- the latch spring 19 is stronger than the latch lock spring 37, so that the operating means is automatically activated.
- the present invention provides a simple, rugged safety latch for well pipe elevators having few parts, so structurally arranged that the operating means for releasing the latch lock and opening the latch can not be inadvertently operated and are protected against damage or operation by engagement by equipment in the derrick.
- a well pipe elevator comprising: an arcuate body having means engageable by elevator links for supporting the elevator in the hoist apparatus of a derrick, a side door pivotally mounted on said body and forming a circular structure for surrounding a well pipe upon closure of the door, latch means for releasably holding said door closed, said latch means including a latch arm pivoted on said body, spring means biasing said latch arm in a latching direction, and latch arm engaging means on said door, latch operating means on said door for actuating said latch arm to a released position, said latch operating means including a unitary lever pivotally mounted on said door, an operating handle on said lever at one side of the pivotal mounting for said lever, latch locking means on said lever at the other side of the pivotal mounting for said lever, said latch locking means including a hook-like end section on said lever and providing aflocking surface disposed within the curve of said hook-like end section adjacent to the free end thereof, said latch arm having a portion adapted to be opposed by said locking surface, and spring means biasing said lever to
- a well pipe elevator comprising: an arcuate body having means engageable by elevator links for supporting the elevator in the hoist apparatus of a derrick; a side door pivotally mounted on said body and forming with said body a circular structure for surrounding a well pipe upon pivoting of said door into closed position, and, upon pivoting of said door into open position, providing a doorway for the lateral insertion into and the lateral removal from said body of a well pipe; latch means for releasably holding said door in said closed position, said latch means including a lug on said door, a latch arm pivoted on said body and pivotable into engagement with said lug when said door is in closed position for holding said door in said closed position; first spring means biasing said latch arm into engagement with said lug, said latch arm being pivotable to a position released from engagement with said lug to permit said door to pivot to open position; an operating lever; pivot means for mounting said operating lever on said door, said operating lever having a first arm extending in one direction from said pivot means and a second arm unitary with said
- a well pipe elevator as defined in claim 4 having cam members on said latch arm and on said hook-like end section that cooperate, as said latch arm is being pivoted into engagement with said lug, to pivot said operating lever into a position in which said internally facing locking surface is in an out-of-the-way position from which it can move into a position confronting said externally facing locking surface upon pivoting of said operating lever in the opposite direction.
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Elevator Door Apparatuses (AREA)
Abstract
Description
Claims (8)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US393085A US3884519A (en) | 1973-08-30 | 1973-08-30 | Safety latch for well pipe elevators |
CA206,009A CA1010441A (en) | 1973-08-30 | 1974-07-31 | Safety latch for well pipe elevators |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US393085A US3884519A (en) | 1973-08-30 | 1973-08-30 | Safety latch for well pipe elevators |
Publications (1)
Publication Number | Publication Date |
---|---|
US3884519A true US3884519A (en) | 1975-05-20 |
Family
ID=23553209
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US393085A Expired - Lifetime US3884519A (en) | 1973-08-30 | 1973-08-30 | Safety latch for well pipe elevators |
Country Status (2)
Country | Link |
---|---|
US (1) | US3884519A (en) |
CA (1) | CA1010441A (en) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070062688A1 (en) * | 2005-09-20 | 2007-03-22 | Mike Schats | Support link for wellbore apparatus |
US20070062705A1 (en) * | 2005-09-20 | 2007-03-22 | Mike Schats | Wellbore rig elevator systems |
US20080150305A1 (en) * | 2006-12-05 | 2008-06-26 | Tesco Corporation | Oilfield elevator |
US20090152409A1 (en) * | 2006-04-28 | 2009-06-18 | Lutzhoeft Jens | Device for Vertically Holding Pipes |
US20130104367A1 (en) * | 2011-10-31 | 2013-05-02 | Forum Us, Inc. | Safety latch lock |
RU2507369C1 (en) * | 2012-09-20 | 2014-02-20 | Закрытое акционерное общество "Научно-производственное предприятие "СибБурМаш" | Elevator for two pipe strings trip |
US20140056647A1 (en) * | 2012-08-27 | 2014-02-27 | Southeast Directional Drilling, Llc | Pipe Retriever |
US20140265389A1 (en) * | 2013-03-15 | 2014-09-18 | T&T Engineering Services, Inc. | Blowout Preventer Lifting Apparatus |
US8979150B1 (en) | 2012-08-31 | 2015-03-17 | Gearench | Tubing elevator latch |
WO2016008668A1 (en) * | 2014-07-18 | 2016-01-21 | Mhwirth Gmbh | Device for holding a pipe segment |
WO2016008669A1 (en) * | 2014-07-18 | 2016-01-21 | Mhwirth Gmbh | Device for holding a pipe segment |
RU2641803C1 (en) * | 2017-03-06 | 2018-01-22 | Публичное акционерное общество "Татнефть" имени В.Д. Шашина | Case elevator |
USD936111S1 (en) * | 2019-03-14 | 2021-11-16 | Forum Us, Inc. | Pipe lifting elevator ear |
US20220136342A1 (en) * | 2020-11-03 | 2022-05-05 | Huangshan Huaneng Petrochemical Machinery Co., Ltd. | Hydraulic rotary side-swing elevator |
US11846145B2 (en) | 2021-04-19 | 2023-12-19 | Gregory Wiedmer | Locking clamp and tubular elevator assembly |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1864864A (en) * | 1930-10-06 | 1932-06-28 | Byron Jackson Co | Friction grip elevator |
US2067663A (en) * | 1935-09-16 | 1937-01-12 | Byron Jackson Co | Elevator and latch construction |
US2257120A (en) * | 1939-10-03 | 1941-09-30 | Byron Jackson Co | Well pipe support |
US2567044A (en) * | 1946-08-09 | 1951-09-04 | Wilson William Webster | Safety latch for elevators |
US2957724A (en) * | 1958-02-03 | 1960-10-25 | Web Wilson Oil Tools Inc | Tool safety latch |
-
1973
- 1973-08-30 US US393085A patent/US3884519A/en not_active Expired - Lifetime
-
1974
- 1974-07-31 CA CA206,009A patent/CA1010441A/en not_active Expired
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1864864A (en) * | 1930-10-06 | 1932-06-28 | Byron Jackson Co | Friction grip elevator |
US2067663A (en) * | 1935-09-16 | 1937-01-12 | Byron Jackson Co | Elevator and latch construction |
US2257120A (en) * | 1939-10-03 | 1941-09-30 | Byron Jackson Co | Well pipe support |
US2567044A (en) * | 1946-08-09 | 1951-09-04 | Wilson William Webster | Safety latch for elevators |
US2957724A (en) * | 1958-02-03 | 1960-10-25 | Web Wilson Oil Tools Inc | Tool safety latch |
Cited By (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070062705A1 (en) * | 2005-09-20 | 2007-03-22 | Mike Schats | Wellbore rig elevator systems |
WO2007034234A2 (en) * | 2005-09-20 | 2007-03-29 | National Oilwell Varco, L.P. | Elevator for handling pipe |
WO2007034235A2 (en) * | 2005-09-20 | 2007-03-29 | Varco I/P, Inc. | A link for supporting a wellbore apparatus and a method for handling pipe |
WO2007034234A3 (en) * | 2005-09-20 | 2007-05-18 | Varco Int | Elevator for handling pipe |
WO2007034235A3 (en) * | 2005-09-20 | 2007-05-18 | Varco Int | A link for supporting a wellbore apparatus and a method for handling pipe |
US7303021B2 (en) | 2005-09-20 | 2007-12-04 | Varco I/P, Inc. | Wellbore rig elevator systems |
US20070062688A1 (en) * | 2005-09-20 | 2007-03-22 | Mike Schats | Support link for wellbore apparatus |
EP2028339A1 (en) * | 2005-09-20 | 2009-02-25 | National Oilwell Varco, L.P. | Elevator for handling pipe |
US8079627B2 (en) * | 2006-04-28 | 2011-12-20 | Blohm + Voss Repair Gmbh | Device for vertically holding pipes |
US20090152409A1 (en) * | 2006-04-28 | 2009-06-18 | Lutzhoeft Jens | Device for Vertically Holding Pipes |
US7866721B2 (en) | 2006-12-05 | 2011-01-11 | Tesco Corporation | Oilfield elevator |
US20080150305A1 (en) * | 2006-12-05 | 2008-06-26 | Tesco Corporation | Oilfield elevator |
US9109409B2 (en) * | 2011-10-31 | 2015-08-18 | Forum Us, Inc. | Safety latch lock |
US20130104367A1 (en) * | 2011-10-31 | 2013-05-02 | Forum Us, Inc. | Safety latch lock |
WO2013066693A1 (en) | 2011-10-31 | 2013-05-10 | Forum Us, Inc. | Safety latch lock |
AU2012332940B2 (en) * | 2011-10-31 | 2017-04-27 | Forum Us, Inc. | Safety latch lock |
EP2773840A4 (en) * | 2011-10-31 | 2016-01-27 | Forum Us Inc | Safety latch lock |
US20140056647A1 (en) * | 2012-08-27 | 2014-02-27 | Southeast Directional Drilling, Llc | Pipe Retriever |
US8851796B2 (en) * | 2012-08-27 | 2014-10-07 | Southeast Directional Drilling, Llc | Pipe retriever |
US8979150B1 (en) | 2012-08-31 | 2015-03-17 | Gearench | Tubing elevator latch |
RU2507369C1 (en) * | 2012-09-20 | 2014-02-20 | Закрытое акционерное общество "Научно-производственное предприятие "СибБурМаш" | Elevator for two pipe strings trip |
US9010820B2 (en) * | 2013-03-15 | 2015-04-21 | T&T Engineering Services, Inc. | Blowout preventer lifting apparatus |
US20140265389A1 (en) * | 2013-03-15 | 2014-09-18 | T&T Engineering Services, Inc. | Blowout Preventer Lifting Apparatus |
WO2016008668A1 (en) * | 2014-07-18 | 2016-01-21 | Mhwirth Gmbh | Device for holding a pipe segment |
WO2016008669A1 (en) * | 2014-07-18 | 2016-01-21 | Mhwirth Gmbh | Device for holding a pipe segment |
RU2641803C1 (en) * | 2017-03-06 | 2018-01-22 | Публичное акционерное общество "Татнефть" имени В.Д. Шашина | Case elevator |
USD936111S1 (en) * | 2019-03-14 | 2021-11-16 | Forum Us, Inc. | Pipe lifting elevator ear |
US20220136342A1 (en) * | 2020-11-03 | 2022-05-05 | Huangshan Huaneng Petrochemical Machinery Co., Ltd. | Hydraulic rotary side-swing elevator |
US11598162B2 (en) * | 2020-11-03 | 2023-03-07 | Huangshan Huaneng Petrochemical Machinery Co., Ltd. | Hydraulic rotary side-swing elevator |
US11846145B2 (en) | 2021-04-19 | 2023-12-19 | Gregory Wiedmer | Locking clamp and tubular elevator assembly |
Also Published As
Publication number | Publication date |
---|---|
CA1010441A (en) | 1977-05-17 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: HUGHES TOOL COMPANY, P.O. BOX 2539, HOUSTON, TX. 7 Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BJ-HUGHES INC.,;REEL/FRAME:004098/0273 Effective date: 19821231 |
|
AS | Assignment |
Owner name: BAKER HUGHES INCORPORATED, TEXAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:HUGHES TOOL COMPANY;REEL/FRAME:005050/0861 Effective date: 19880609 |
|
AS | Assignment |
Owner name: HUGHES TOOL COMPANY-USA, 5425 POLK AVE., HOUSTON, Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BAKER HUGHES INCORPORATED;REEL/FRAME:004944/0763 Effective date: 19880718 Owner name: HUGHES TOOL COMPANY-USA, A DE CORP.,TEXAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BAKER HUGHES INCORPORATED;REEL/FRAME:004944/0763 Effective date: 19880718 |
|
AS | Assignment |
Owner name: VARCO INTERNATIONAL, INC., A CA. CORP., CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:HUGHES TOOL CONPANY-USA;REEL/FRAME:005013/0843 Effective date: 19880929 |