US3365175A - Travel limiting device for the travelling block of hoisting installations provided with pneumatic controls - Google Patents
Travel limiting device for the travelling block of hoisting installations provided with pneumatic controls Download PDFInfo
- Publication number
- US3365175A US3365175A US442465A US44246565A US3365175A US 3365175 A US3365175 A US 3365175A US 442465 A US442465 A US 442465A US 44246565 A US44246565 A US 44246565A US 3365175 A US3365175 A US 3365175A
- Authority
- US
- United States
- Prior art keywords
- valve
- inlet
- orifice
- pneumatic
- outlet
- 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
- 238000009434 installation Methods 0.000 title claims description 12
- 230000007246 mechanism Effects 0.000 claims description 6
- 238000004353 relayed correlation spectroscopy Methods 0.000 claims 6
- 238000005553 drilling Methods 0.000 description 11
- 230000009471 action Effects 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 2
- 230000000740 bleeding effect Effects 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D67/00—Combinations of couplings and brakes; Combinations of clutches and brakes
- F16D67/02—Clutch-brake combinations
- F16D67/04—Clutch-brake combinations fluid actuated
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
- B66D1/00—Rope, cable, or chain winding mechanisms; Capstans
- B66D1/02—Driving gear
- B66D1/08—Driving gear incorporating fluid motors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
- B66D1/00—Rope, cable, or chain winding mechanisms; Capstans
- B66D1/02—Driving gear
- B66D1/14—Power transmissions between power sources and drums or barrels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
- B66D2700/00—Capstans, winches or hoists
- B66D2700/01—Winches, capstans or pivots
- B66D2700/0125—Motor operated winches
- B66D2700/0133—Fluid actuated
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
- B66D2700/00—Capstans, winches or hoists
- B66D2700/01—Winches, capstans or pivots
- B66D2700/0125—Motor operated winches
- B66D2700/0158—Hydraulically controlled couplings or gearings
Definitions
- This invention relates to a limiting device for the travel of the travelling block used in conjunction with drilling rigs, hoists and similar installations.
- a travel limiting device for the travelling block of draw works is already known in the art.
- the stopping operation is effectuated by means of an air valve (mounted on the derrick floor) and actuated directly by the travelling block, by means of a cable line.
- This known device presents the disadvantage of having the control valve mounted on the derrick floor and close to the rotary table of the derrick, which causes it to be exposed to bad weather and to the corrosive action of the water and drilling fluid. Since this device is idle most of the time, the valve can easily become stuck. Thus, conditions can occur when the valve counterweight is not great enough to actuate a stuck valve of the device.
- the connecting cable line being quite thin, it has been found to be prone to be carried away by the drilling line, which causes it to enter between the travelling block sheaves and wire rope, thus damaging the device.
- travelling block travel limiting device which can be mounted in the drilling rig derricks.
- This known device has a safety valve attached to the draw works, and is actuated-at a preselected moment-by the layers of drilling line spooled onto the hoisting drum.
- the safety valve of this known device stops the travelling lock at a safe level in the derrick, by actuating the hoisting drum brake and simultaneously therewith disengaging the power groups from the draw works.
- This known device presents the shortcoming that in case of an irregular spooling of the drilling line which can happen quite frequently, the layers of drilling line can get interpenetrated (wraps belonging to the upper layer can get inbetween the lower layer wraps) and, consequently, the device can stop the travelling block too early, or too late, the latter case being quite dangerous.
- This invention relates to a travel limiting device for travelling blocks belonging to hoisting installations and comprises a threaded rod with a nut mounted thereon which is driven by the hoisting drum shaft; a pneumatic stop valve which actuates a control relay, by means of which, and depending on the nut position on the threaded rod, the air passage to the hoisting drum clutch is opened or closed, and concomitantly therewith the hoisting drum is accordingly started or stopped.
- This hoisting drum stoppage is effectuated by means of the pneumatic drum brake, which is activated by means of a switch valve and a brake release valve which brings out of action the hoisting drum and respectively stops automatically the travel- "ice ling block at a safe height established by an initial adjustment.
- This adjustment consists of conveniently rotating the aforementioned threaded rod until the nut, which is moving on it, trips the pneumatic stop valve at the desired moment.
- FIG. 1 is a schematic illustration of a travelling block travel limiting device according to this invention, attached to a. drilling rig, without an automatic hoisting drum stop
- FIG. 2 is a schematic illustration of the same device, as illustrated in FIG. 1, but with an automatic hoisting drum stop.
- Example I The device, according to the invention and illustrated in FIG. 1 comprises a driving wheel 1, coaxially attached to the hoisting drum shaft 2, which in turn drives a threaded rod 5 by means of a chain 3, a sprocket wheel 4 and a transmission arrangement 6 (bevel gear, helical gear, worm gear, etc., transmission).
- a driving wheel 1 coaxially attached to the hoisting drum shaft 2 which in turn drives a threaded rod 5 by means of a chain 3, a sprocket wheel 4 and a transmission arrangement 6 (bevel gear, helical gear, worm gear, etc., transmission).
- the sprocket wheel 4 is secured to its supporting shaft by means of a cone, which is used for adjusting the device in accordance with the number of travelling block lines, respectively in accordance with the maximum allowable height.
- the structure of the adjusting cone is stand ard and, consequently, well known in the art and has not been illustrated in detail.
- the installation includes also a nut 7 which can be shifted, without rotating it, along the threaded rod 5.
- a pneumatic stop valve A which is actuated by a pivotable control lever 8 having a roller at its free end, and a main relay B, both of which are connected together by means of the air lines 9 and are also connected to the main compressed air system 10 for the device.
- the pneumatic stop valve A comprises a housing 11 having a vent opening at one end thereof, a valve member 12 axially movably mounted therein, a spring 13, urging the valve member 12 into a closed position, and a valve member 14 with a control rod, which cooperates with the lever 8.
- the housing 11 is provided with a compressed air supply inlet orifice 15 and an outlet orifice 16, which allows the air to pass towards the main relay B.
- the main relay B comprises a housing 17 composed of three compartments and a lid 18.
- a rubber diaphragm 19 is mounted between the lid 18 and the lower ends of the outer walls of the housing 17.
- the diaphragm 19 is urged upwardly by a coil spring 20.
- valve member 22 Inside the housing 17 there is mounted a valve member 22 which cooperates with the valve seat member 21 and the valve seat 21a.
- a valve closing spring 23 acts on the valve member 22.
- the housing 17 is provided with an orifice 24 through which the air is entering from the stop valve A.
- An orifice 25 in the wall of housing 17 serves as an inlet for the air supply, and an orifice 26 in the wall of housing 17 provides an outlet for the air to pass towards the clutch (not shown).
- An orifice 27 in the housing 17 permits a bleeding off of the air from the clutch. The compressed air passing through opening 27 is released into the atmosphere.
- the device of this invention operates as follows:
- the travelling block is brought to the upper limit position, the sprocket wheel 4 is loosened and the shaft is rotated by means of a wrench (not shown) 3 until the nut 7-which is shifted along the threaded rod 5 by means of the drive 6strikes the control lever 8, thereby tripping the device. in this position, the sprocket wheel 4 is again fastened onto its corresponding supporting shaft by means of its locking cone and lock nut.
- the nut 7 shifts along the rod 5 in one direction or another without striking the control lever 8; the compressed air from the main line 11 can not pass towards the relay B, through the orifice 24, because the valve member 12 from the stop valve A is in its closed position, but it can pass through the relay B orifice 25, and because the valve member 22 is in its open position, the air can pass freely through the orifice 26 towards the reverser or hoisting drum clutch (not shown) and, consequently, the drum is placed in its working position.
- valve member 12 closes the passage for the compressed air towards the space in communication with the orifice 16. It should also be noted that during the operation of the device the orifice 15 never comes directly into communication with the atmosphere, which would result in unnecessary losses of compressed air.
- the orifice 16 communicates with the atmosphere via the space between the right hand plate 12b of the valve member 12 and through the central passage 14a of the valve member 14 and through the vent opening 11a at the right end wall of the valve housing 11.
- valve member 14 When the valve member 14 is pushed inwards, it meets first the right hand plate 12b of valve member 12 thereby closing the communication between the orifice 16 and the atmosphere. Continuing its inward stroke, valve member 14 pushes valve member 12 toward the left thereby lifting the left hand plate 12a from its valve seat and placing orifice 15 in communication with orifice 16.
- valve member 14 On the other hand when the valve member 14 is again pushed outwardly by the springs 12c and 13, the valve member 12 follows, due to the action of the spring 13, thereby cutting off the connection between the orifices 15 and 16 by repositioning the plate 12a on its valve seat.
- the valve member 14, which continues its outward movement, can no longer be followed by the valve member 12 and, consequently, the right hand plate 12b lifts off the opening for the passage 14a thereby establishing a communication between the orifice 16 and the atmosphere.
- the main relay B works as follows when the stop valve A assumes the aforedescribed two positions:
- both the relay B and the stop valve A operate similarly in principle i.e. first the flow path between the orifice 25 and the atmosphere is closed and only afterwards the flow path between the source of compressed air and the orifice 26 is opened. This is due to the similar operation of the valve member pairs 12, 14 and 21, 22.
- valve member 22 closes the entrance of the compressed air towards the clutches (not shown); the air from the drum and reverser clutches is bled off into the atmosphere through the central orifice of the valve seat member 21 and through the bleeder orifice 27, thereby uncouples the hoisting drum from its drive. Simultaneously with the drum uncoupling the travelling block is stopped.
- the above mentioned safety device uncouples all the rig clutches including those provided for the engines, and in this case it insures the complete protection of the rig even in the case when due to diverse reasons, the drawworks and reverser clutches got stuck.
- Example II The device according to this invention illustrated in FIG. 2 comprises a driving wheel 28 attached to a hoisting drum shaft 29, which in its turn is driving by means of a chain 30, a sprocket wheel 31, which is fastened onto its supporting shaft by means of a cone which is used for the adjustment of the device.
- the adjustment is made in accordance with the number of cable lines on the travelling block, respectively in accordance with the maximum height allowed for the travelling block travel.
- the structure of the adjusting cone is standard and consequently well known in the art and has not been illustrated in detail.
- gear 32 (which can be cylindrical, bevel, helical or worm gear) there is driven the gear wheel 33 which is axially secured to the threaded rod 34.
- the device includes also a nut 35, which can be longi tudinally shifted-without rotatingalong a threaded rod 34.
- a pneumatic stop valve C is actuated in its turn by a control lever 36 having a roller at its free end.
- the device further includes main relay D, a releasing valve E, a switch valve F, a hoisting drum control valve G and a control valve H for the hoisting drum pneumatic brake, all of which form part of the device and are operatively connected to each other in an arrangement that will be set forth below.
- the pneumatic stop valve C comprises a valve body 37, a control and unload valve member 38 axially movably mounted in the valve body 37.
- a spring 39 is mounted inside a cavity of the valve body 37.
- a stop valve member 40 actuated by a valve spring 41 is mounted inside a valve seat member 42.
- a threaded guide member cover 43 is axially mounted in the lower end of the valve body 37 and seals a compartment situated therein and serves also to guide the valve member 40.
- the valve body 37 is provided with an inlet orifice 44 for compressed air feeding, and an orifice 45 for letting air pass towards the main relay D.
- the main relay D comprises a valve housing 46, a valve member 47 axially movably mounted therein, a double valve seat 48 mounted inside the housing 46.
- a coil spring 49 urges the valve member 47 downwardly into a closed position.
- a threaded lid 50 having a central bore is threadably mounted into the upper end of the housing 46.
- the housing is provided with an orifice 51 for air inlet from the stop valve C; an orifice 52 for compressed air feeding from the main compressed air feeder line 67, an orifice 53 for permitting air to pass towards the hoisting drum clutch and the aforementioned orifice 54 for air bleed-off into the atmosphere.
- the release valve E comprises a valve cylinder 55, in which there is axially movably mounted a distribution piston 56.
- a button lid 57 is secured to the lower end of the piston 56.
- a reset spring 58 urges the button lid 57 downwardly.
- the valve cylinder is provided with an orifice 59 which acts as an air inlet for air coming from the switch valve F; an orifice 60 which acts as an air outlet for air passing towards a pneumatic brake for the hoisting drum; and an orifice 61 for bleeding ofi the air into the atmosphere.
- the switch valve F is composed of a body 62 and a switch piston 63 axially movably mounted therein.
- the body 62 is provided with the orifices 64, 65 and 66, the functions of which will be set forth below.
- the stop valve C, the main relay D, the release valve E, the switch valve F and the control valves G and H are connected together by a series of lines through which the compressed air is effectuated from the main pipe line 67.
- the device operates as follows:
- the travelling block is brought to its upper limit position; the sprocket wheel 31 is loosened and the shaft 34 is turned by means of a wrench (not shown), until the nut 35 strikes the control lever 36, thereby tripping the device.
- the sprocket wheel 31 is fastened onto its corresponding shaft, by means of the locking cone and lock nut.
- the nut 35 is shifting, in one direction or another, along the threaded rod 34 without striking the control lever 36; while the control lever 36 is not tripped the compressed air from the main line 67 can not pass towards the relay D through the orifice 51, because the valve member 40 of the stop valve C remains in its closed position; however, the compressed air can pass during this time through the orifice 52 and relay D, and from there through the double valve seat 48 and orifice 53, the air then being further directed towards the hoisting drum clutch, through the intermediary control valve G, thus placing the drum in its working position.
- valve member 38 of the stop valve When the nut 35 strikes the lever 36, the valve member 38 of the stop valve is pushed towards the interior by the lever 36, thus shutting off the air release into the atmosphere of air passing along valve member 38. Concomitantly therewith the valve member 40 is opened and the compressed air coming from the orifice 44 now passes through the orifices 45 and 51 towards the relay D. Consequently, the valve member 47 shuts off the air entering from the main line 67 (through orifice 52) by moving upward the valve member 47 and seating it on the lower seat of the double valve seat 48.
- the drum 29 is uncoupled because the air from the clutch is bled off into the atmosphere via the valve G, the orifice 53, the upper 6 seat of the double valve seat 48 and finally through the orifice 54.
- the restarting of the hoisting drum 29 requires the following operations to be performed:
- the unloading valve E button is pushed, thereby blocking orifice 59, and the air from the hoisting drum pneumatic brake can then be bled off into the atmosphere, passing first through orifice 60, then around the distribution piston 56 annular space and finally through the atmosphere through orifice 61.
- the drum can be unwound (the drum brake being manually controlled) until the contact between the nut 35 and control lever 36 is broken.
- the stop valve C by the action of spring 41, closes the air entrance towards the main relay D (the valve member 40 is seated on its seat 42) opening at the same time to the atmosphere the compressed air in the air line 68, through the orifice 45 and the valve member 38 central exhaust port.
- a travel limiting mechanism including a drum for spooling a cable thereon which is operatively mounted in said installation; a pneumatically actuated clutch operatively connected to said drum; stop valve means having an inlet and outlet; a first valve member reciprocally mounted in said stop valve means and responsive to rotation of said drum; pneumatic relay Valve means having a first inlet, a first outlet, a second inlet, and a second outlet; the first inlet of said pneumatic relay valve means being in communication with the outlet of said stop valve means, the inlet of said stop valve means being in communication with said pneumatic source of power and the first outlet of said pneumatic relay valve means being in communication with said pneumatically actuated clutch and with said second inlet; said second inlet being in communication with said pneumatic source of power; a second valve member reciprocally mounted in said relay valve means; said first and second valve members being adapted to respectively cooperate with the inlets and outlets of said stop valve means and pneumatic
- a travel limiting mechanism as set forth in claim 1, including pneumatic brake means operatively connected to said drum, a distributor valve pneumatically connected on the one hand to said pneumatic source of power and further being pneumatically connected to said stop valve means and said pneumatic brake, whereby when said stop valve means is actuated it also effects a pneumatic communication of said pneumatic brake with said pneumatic source of power via said distributor valve, thereby activating said pneumatic brake and braking the movement of said drum.
- a travel limiting mechanism as set forth in claim 2, including means operatively connecting said drum to said first valve member, said means comprising adjustable gear means operatively connecting said drum, a lever pivotally mounted in said travel mechanism adjacent to said pneumatic stop valve means, said lever being adapted to be tripped by said first valve member, a threaded rod rotatably mounted adja: cent to said lever and being operatively connected to said adjustable gear means so as to be rotated by them, a nut threadably mounted on said rod and adapted to move to and fro on said rod depending on the direction of rotation thereof, said nut being adapted to trip said lever when said drum has passed said preselected limit position.
- a travel limiting mechanism as set forth in claim 3, including a changeover valve mounted on the one hand, between said pneumatic source of power and said distributor valve and being pneumatically connected thereto, and on the other hand, between said stop valve means and said distributor valve and being pneumatically connected thereto.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Earth Drilling (AREA)
- Braking Arrangements (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
RO4774164 | 1964-03-31 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3365175A true US3365175A (en) | 1968-01-23 |
Family
ID=20086446
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US442465A Expired - Lifetime US3365175A (en) | 1964-03-31 | 1965-03-24 | Travel limiting device for the travelling block of hoisting installations provided with pneumatic controls |
Country Status (4)
Country | Link |
---|---|
US (1) | US3365175A (de) |
AT (1) | AT262556B (de) |
GB (1) | GB1043974A (de) |
NL (1) | NL6503846A (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3960362A (en) * | 1974-10-08 | 1976-06-01 | Eaton Corporation | Hoist control with limit switches |
US5465939A (en) * | 1993-10-22 | 1995-11-14 | Ingersoll-Rand Company | Directional control assembly for an air winch |
CN103508351A (zh) * | 2013-09-09 | 2014-01-15 | 武汉船用机械有限责任公司 | 一种排缆器 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US774767A (en) * | 1904-04-04 | 1904-11-15 | Fred W Lyon | Safety attachment for hoisting-engines. |
US963384A (en) * | 1910-07-05 | Robert A Ogle | Hoisting-machine. | |
US1452964A (en) * | 1921-04-09 | 1923-04-24 | Gillis & Geoghegan | Hoisting mechanism |
US2376019A (en) * | 1943-08-09 | 1945-05-15 | Thomas W Thomas | Boom stop |
US2502710A (en) * | 1946-04-02 | 1950-04-04 | Emsco Derrick & Equip Co | Safety stop for drum travel |
US2656027A (en) * | 1950-05-13 | 1953-10-20 | Standard Oil Dev Co | Position control device |
-
1965
- 1965-03-24 US US442465A patent/US3365175A/en not_active Expired - Lifetime
- 1965-03-25 NL NL6503846A patent/NL6503846A/xx unknown
- 1965-03-30 AT AT289265A patent/AT262556B/de active
- 1965-03-31 GB GB13557/65A patent/GB1043974A/en not_active Expired
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US963384A (en) * | 1910-07-05 | Robert A Ogle | Hoisting-machine. | |
US774767A (en) * | 1904-04-04 | 1904-11-15 | Fred W Lyon | Safety attachment for hoisting-engines. |
US1452964A (en) * | 1921-04-09 | 1923-04-24 | Gillis & Geoghegan | Hoisting mechanism |
US2376019A (en) * | 1943-08-09 | 1945-05-15 | Thomas W Thomas | Boom stop |
US2502710A (en) * | 1946-04-02 | 1950-04-04 | Emsco Derrick & Equip Co | Safety stop for drum travel |
US2656027A (en) * | 1950-05-13 | 1953-10-20 | Standard Oil Dev Co | Position control device |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3960362A (en) * | 1974-10-08 | 1976-06-01 | Eaton Corporation | Hoist control with limit switches |
US5465939A (en) * | 1993-10-22 | 1995-11-14 | Ingersoll-Rand Company | Directional control assembly for an air winch |
CN103508351A (zh) * | 2013-09-09 | 2014-01-15 | 武汉船用机械有限责任公司 | 一种排缆器 |
CN103508351B (zh) * | 2013-09-09 | 2015-12-02 | 武汉船用机械有限责任公司 | 一种排缆器 |
Also Published As
Publication number | Publication date |
---|---|
NL6503846A (de) | 1965-10-01 |
AT262556B (de) | 1968-06-25 |
GB1043974A (en) | 1966-09-28 |
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