GB1342741A - - Google Patents
Info
- Publication number
- GB1342741A GB1342741A GB353170A GB1342741DA GB1342741A GB 1342741 A GB1342741 A GB 1342741A GB 353170 A GB353170 A GB 353170A GB 1342741D A GB1342741D A GB 1342741DA GB 1342741 A GB1342741 A GB 1342741A
- Authority
- GB
- United Kingdom
- Prior art keywords
- valve
- fluid
- pressure
- support
- jan
- 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
Links
- 239000012530 fluid Substances 0.000 abstract 7
- 238000010276 construction Methods 0.000 abstract 1
- 230000000881 depressing effect Effects 0.000 abstract 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
- E21D15/50—Component parts or details of props
- E21D15/51—Component parts or details of props specially adapted to hydraulic, pneumatic, or hydraulic-pneumatic props, e.g. arrangements of relief valves
- E21D15/512—Arrangement of valves
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Structural Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Safety Valves (AREA)
Abstract
1342741 Mine roof supports WE & F DOBSON Ltd 19 Jan 1971 [24 Jan 1970] 3531/70 Heading F1D A mine roof support, Fig. 1, comprising a piston & cylinder both of hollow construction has a valve assembly Fig. 3, which includes a valve 29 for releasing fluid when the pressure in the support increases slowly and a valve 30 which releases fluid when a sudden increase in pressure occurs. A member 96 slides in & out to provide an indication of the pressure in the device. Fluid under pressure passes from the cylinder into a chamber 45 and through a bleed passage 47 in the valve 30 into a chamber 48 which communicates with the valve 29 which is of the "Marshalsea" type. Any sudden pressure increase opens the valve 30 by moving a member 42 to the right against a spring 53. This allows fluid to pass a seat 41 and escape through an orifice 63. Fluid passes through the bleed hole 47 until pressure builds up and the member 42 moves to the left again. Fluid may be manually released by depressing a plunger 60, 61 to unseat a ball valve 49. Fluid is supplied to the support through a non-return ball valve 81. Specification 1332152 is referred to.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB353170 | 1970-01-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1342741A true GB1342741A (en) | 1974-01-03 |
Family
ID=9760089
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB353170A Expired GB1342741A (en) | 1970-01-24 | 1970-01-24 |
Country Status (3)
| Country | Link |
|---|---|
| DE (1) | DE2042295A1 (en) |
| GB (1) | GB1342741A (en) |
| ZA (1) | ZA711598B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115023533A (en) * | 2019-11-11 | 2022-09-06 | J.雷.麦克德莫特股份有限公司 | Destructive coupling system and method for subsea systems |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4237769A (en) * | 1978-04-03 | 1980-12-09 | Commercial Shearing, Inc. | Relief valves and mine props incorporating the same |
| GB2069048B (en) * | 1980-01-21 | 1984-06-06 | Commercial Shearing | Longwall jacks |
| DE4012481C2 (en) * | 1990-04-19 | 2002-04-25 | Dbt Gmbh | Valve device with a hydraulically unlockable check valve for hydraulic mining systems, especially for hydraulic expansion systems |
-
1970
- 1970-01-24 GB GB353170A patent/GB1342741A/en not_active Expired
- 1970-08-26 DE DE19702042295 patent/DE2042295A1/en active Pending
-
1971
- 1971-03-11 ZA ZA711598A patent/ZA711598B/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115023533A (en) * | 2019-11-11 | 2022-09-06 | J.雷.麦克德莫特股份有限公司 | Destructive coupling system and method for subsea systems |
Also Published As
| Publication number | Publication date |
|---|---|
| ZA711598B (en) | 1971-12-29 |
| DE2042295A1 (en) | 1972-05-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PLNP | Patent lapsed through nonpayment of renewal fees |