GB2223044A

GB2223044A - Setting mine roof arches

Info

Publication number: GB2223044A
Application number: GB8822364A
Authority: GB
Inventors: Rodney Vincent Nichols
Original assignee: Coal Industry Patents Ltd
Current assignee: Coal Industry Patents Ltd
Priority date: 1988-09-22
Filing date: 1988-09-22
Publication date: 1990-03-28
Also published as: GB8822364D0

Abstract

Arches are set in a mine passage 1 by placing arch sections 3, 4 constituting the crown of the arch on a fixture which forms the sections to a gothic arch. A support platform carried by a monorail advances the fixture and the arch sections to the front of the passageway (9 Fig 1) where the platform raises the arch sections to the roof of the passage where they are secured. A temporary support 28 holds the fixture 20 in position while leg arch sections 5, 6 are secured. <IMAGE>

Description

IMPROVEMENTS RELATING TO ARCH SETTING This invention relates to a method and apparatus for setting an arch in an underground passage in which the arch is constituted by a plurality of components secured together, the components comprising a first plurality of arch sections forming in use the crown of the arch and a second plurality of arch sections forming in use leg supports.

In passages formed in underground workings such as coal mines the passages or roadways as they are often called are formed by a driving machine which cuts at the head of the passage and extracts material from the face. This material is then carried away from the face and the freshly excavated area is supported by arches which have to be set against the roof and the walls of the newly created area of the passage.

Alternatively the face of the passage is mined by shot firing where holes are drilled into the face and explosive is placed in these holes. The explosive is then detonated bringing about a fall of material at the face end of the passage and this fall in material is first removed, usually by a mechanical excavator with manual assistance, before the arches can be set to support the newly exposed face.

As soon as excavation or shot firing has taken place the unsupported area of the passage becomes a very dangerous place for personnel to work in. The strata surrounding the newly exposed area is stress relieved and falls of the material can occur. It is thus essential to provide the maximum amount of cover for personnel who have to work in this area and to reduce where possible the number of personnel working. It is also essential to ensure that arches are set as soon as possible so that no fall from the newly exposed area takes place.

In order to set the arches platforms can be erected on which arch setters can stand while the arches are raised into position first against the roof of the newly exposed passage area and against the walls. The arches are secured, struts are placed to secure the newly set arch to the adjacent arch and if necessary lagging boards are placed behind the struts. While this is taking place the personnel concerned are exposed to the risk of falls from the roof.

In order to minimize these risks mechanical means have been suggested which include platforms which can be carried on the end of excavating or roadway clearing machines and some of these include a temporary form of canopy which can extend over the operator. However, the operator is always at some risk since he must at some stage be in a vulnerable position outside the canopy while the physical connections are made to the various sections of the arch.

Furthermore, the use of arch setting platforms carried on mining machinery does cause problems in itself in as much as platforms have to be stored in the passageway away from the face during work on the face and the machinery is therefore limited in its useful time whilst manoeuvring of the platforms take place.

It is an object of the present invention to provide a method and apparatus of setting an arch which interferes to a lesser extent with the normal excavating process and which does not require removal of equipment for the dual use of equipment during arch setting and therefore enables arch setting to be speeded up.

According to a first aspect of the present invention a method of setting an arch in an underground passage is provided in which the arch is constituted by a plurality of components secured together, the components consisting of a first plurality of arch sections forming in use the crown of the arch and a second plurality of arch sections forming in use leg supports, and comprises the steps of forming the first plurality of sections into a distorted arch configuration such as to pass readily within the passage, advancing the configuration to a forward location in the passage, raising the configuration to the roof of the passage at the location and adjusting the sections to the profile of the roof of the passage to form an arch, securing the sections to retain this profile and subsequently securing the second plurality of arch sections to provide leg supports.

The method can include arranging the first plurality of arch sections on a fixture, the fixture being dimensioned so as to move freely within the passage carrying the sections in the distorted arch configuration.

A temporary support may be applied to the first plurality of arch sections whilst the second plurality of arch sections are connected thereto to form the leg supports.

Struts are preferably applied to the first plurality of arch sections before it is advanced to the forward location in the passage and lagging may also be applied as well. Further lagging may be applied to the arch once the leg supports are secured in position.

The distorted arch configuration and any fixture carrying it is preferably formed as a gothic arch having a span which allows it to pass freely over any machinery working in the heading of the passage.

Preferably the distorted arch configuration is carried by an overhead monorail transport device. The invention also includes the steps of adding further sections to the monorail to extend it by connecting these further sections to the newly set arches.

Conveniently the arch configuration is arranged in a vertical form on the floor of the passage away from the face and it is then lifted to a position for transport to the location.

Advantageously a working platform may be combined with the monorail transport device at the rear thereof in order to enable equipment readily to be transported by the monorail device. This working platform is preferably able to be raised to the roof to allow a free passage of machinery in the passage below the working platform.

According to another aspect of the present invention apparatus for use with the method includes a monorail suspended from previously set arches and includes a powered unit for carrying adjustable means for transporting the arch configuration and raising it into position. The means is preferably hydraulically operated.

The apparatus may include a fixture adapted to receive arch sections and to be suspended from the arm of the monorail.

In order that the invention may be fully understood one example of arch setting apparatus in accordance therewith and using the method thereof will now be explained with reference to the two figures of the accompanying drawings. In the drawings figure 1 shows the sections through a mine roadway which is supported by arches and figure 2 shows a sectional view through the roadway near its face.

The roadway 1 is supported by plurality of arches 2 each spaced along the length of the roadway 1 by a set distance.

Normally the arches are spaced by support struts which in this example are omitted for clarity. Each of the arches 2 is comprised of two arch sections 3, 4 and two leg sections 5, 6. A monorail 7 is suspended from the centre of the arches 2 and carries a drive tug 8 which has its forward end, i.e. the end nearest the face 9 being excavated, a support member 10 which includes a support platform 11 carried at the end of articulated arms 12 which are hydraulically operated as shown at 13. The drive tug 8 carries at its rear end a working platform 14 at the end of parallel arms 15 which can be operated by a hydraulic cylinder 16 to raise and lower the working platform 14.

A fixture shown generally at 20 is used to set the arches and to position them initially before they are placed in their correct location. At any one time there are three or four fixtures 20 in use and each fixture is identical comprising the pair of winged rear parts 21, 22 which are hinged together at the top at 23. At the bottom of each hinged part there is a front extension member 24 and this is connected to a corresponding winged pair of front parts of which only one 25 is shown. Other extension members 26 also connect the front and rear parts to hold them rigid.

In operation, to set an arch one of the fixtures 20 is arranged down the roadway 1 to the rear of any excavating machine such as that indicated in dotted line at 27. The fixture has fitted to it arch sections 3, 4. In figure 2 these are shown as arch sections 3, 4 respectively and these lie on the winged rear parts 21, 22 of the fixture. It will be seen from figure 2 that the fixture in its raised position as shown is able to pass easily within the length of the roadway and to clear easily the excavating machine 27. This means that it is not necessary to move the excavating machine in order that the arch sections 3, 4 can be placed into position.

When the fixture which is set up on the floor of the roadway has been fitted with the arches 3, 4 it is lifted by the support platform 11 to the position shown in figure 2. The whole of the monorail drive tug 8 and associated platforms are not shown in figure 2 for clarity.

When the support platform has picked up the arch sections 3, 4 it carries them in their gothic form forward through all the other arches 2, over the excavating machine 27 to the front of the roadway adjacent to the face 9. The platform is then raised to a position so that the winged parts 21, 22 can be pivoted outwards by the hinge 23 to bring the arch sections 3, 4 against the freshly excavated roof of the roadway 1. Conventional fish plates (not shown) are then secured between the arch sections 3, 4 at their apex to hold them rigidly with respect to each other. At the same time a temporary hydraulic prop 28 is placed under the end of each winged front part 25 and is adjusted to give temporary support to the whole of the fixture and the two arch sections on it.

The appropriate leg sections 5 and 6 are then secured by bolting to the arch sections 3, 4 and provide a rigid permanent support.

The support platform 11 is now lowered leaving the whole of the fixture into position and the drive tug 8 moves the platform 11 backwards until the platform 11 is under the most rear end fixture which in this example is one which is fourth from the face as shown in figure 1.

The platform 11 is raised to engage the fixture and the appropriate temporary support 28 is withdrawn and the fixture now rests solely on the platform 11. The fixture is lowered and relaxed into its gothic position and the drive tug then takes it back down the roadway 1 to a position where the next arch sections can be assembled on it, for the whole process to be repeated.

In the description of the operation of the invention so far only the setting of the arch has been described in simple terms.

In practice struts which connect between adjacent arches will need to be fitted and these are fitted in appropriate slots in the periphery of the fixture so as roughly to locate the struts sufficient to allow the movement of the struts and tightening of the bolts when the arches are in position.

In order also to add to the safety of the operators it is possible for lagging sheets to be applied at the same time as the fixture is loaded with the arches. Lagging sheets such as those indicated at 29 are connected to each arch section 3, 4 and project forward of it towards the face 9. These lagging sheets are connected by any suitable means such as tabbing or projections on the arch sections extending into slots in the lagging or by using individual lagging clips. The lagging sheets are designed not to lie parallel to the centre of the roadway but to project up slightly from it in a forward direction. This can be observed in figure 1.The lagging sheets extend forward over the front of the winged front plates 25 of the section and when the most forward fixture is moved into position and raised up the rear of the lagging plates are raised to come into contact with the front underside of the immediately preceding set of lagging plates on the preceding arches. This is clearly illustrated in figure 1. In this way maximum protection is given to personnel setting the arches during the whole of the process and particulary while the temporary props 28 are being set. There is thus very little risk from roof falls for the personnel involved.

The monorail itself which carries the drive tug 8 is made up of sections. As can be seen from figure 1 each section of the monorail spans 3 arches. Thus when three arches have been set the monorail must be extended before a further arch can be set.

The working platform 14 carried at the rear of the drive tug 8 is very useful for detaching monorail sections if this is necessary and also for enabling personnel to fix services such as pipes, cables and conduits to the arches in a safe manner.

It will be appreciated from the foregoing description that the method and apparatus for setting arches which has been described enables the arches to be set in position in the manner which maximizes the space available and does not interfere with normal operations. The arches are able to be placed on the fixture to the rear of any working area where a roadway heading is being cut and can then be moved to support the area immediately it has been exposed without the need to move any excavating machinery out of the way other than to lower the boom of the machine. This will give a great saving in working time in operating the drivage of roadways.

In a situation where the heading of the roadway is being prepared by shot firing rather than by the use of an excavating machine the invention is equally applicable although the drive tug will have to be used to withdraw the support platform 11 from the firing area each time the firing takes place. Machines for clearing up the shot debris can operate effectively within the area defined by the fixture 20 and the fixture 20 will not inhibit the movement and use of such machines.

Claims

1. A method of setting an arch in an underground passage in which the arch is constituted by a plurality of components secured together, the components comprising a first plurality of arch sections forming in use the crown and the second plurality of arch sections forming in use leg supports, comprising the steps of forming the first plurality of sections into a distorted arch configuration such as to pass readily within the passage, advancing the configuration to a forward location in the passage, raising the configuration to the roof of the passage at the location and adjusting the sections to the profile of the roof of the passage to form an arch, securing the sections to retain this profile and subsequently securing the second plurality of sections to provide leg supports.

2. A method as claimed in claim 1 and including a fixture to support the arch sections, the fixture being arranged to fit under the set arches.

3. The method as claimed in claim 1 or claim 2 and including the step of applying the temporary support to the arch or the fixture while the leg support arch sections are set.

4. The method as claimed in any preceding claim and including applying struts to the arch sections prior to their being advanced to the forward location in the passage.

5. The method as claimed in any preceding claim and including applying lagging to the arch sections and transporting the lagging with the arch sections to the forward location.

6. The method as claimed in claim 5 and including applying further lagging to the arch after the leg support sections have been properly positioned.

7. The method as claimed in any preceding claim in which the distorted arch configuration is in the form of a gothic arch such as to enable it to pass freely over any machinery working in the heading of the passage.

8. The method as claimed in any preceding claim and including the step of transporting the configuration on an overhead monorail.

9. The method as claimed in claim 8 and including the step of securing further monorail sections to the arches as succeeding arches are set.

10. The method as claimed in any preceding claim including the preliminary step of assembling the arch sections in a vertical form on the floor of the passageway and then lifting in the assembled form to a position for transport to the location.

11. Apparatus for use with a method as claimed in any preceding claim and including a monorail suspended from previously set arches in a passageway, a powered unit suspended from the monorail being arranged to move the arch sections along the monorail to the forward position.

12. Apparatus as claimed in claim 11 in which the monorail includes a support platform adapted to receive a fixture supporting the arches, the support platform, being raised and lowered through articulated arms which are hydraulically operated.

13. The method of setting an arch in an underground passage substantially as herein before described and with reference to the accompanying drawings.

13. Apparatus as claimed in claim 11, or claim 12 and including a working platform associated with the monorail, the working platform being hydraulically operated to raise and lower the platform within the passageway.

14. The method of setting an arch in an underground passage substantially as herein before described and with reference to the accompanying drawings.

AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS 1. A method of setting an arch in an underground passage in which the arch is constituted by a plurality of components secured together, the components comprising a first plurality of arch sections forming in use the crown and the second plurality of arch sections forming in use leg supports, comprising the steps of forming the first plurality of sections into a distorted arch configuration such as to pass readily within the passage, transporting the configuration on an overhead monorail to a forward location in the passage, raising the configuration to the roof of the passage at the location and adjusting the sections to the profile of the roof of the passage to form an arch, securing the sections to retain this profile and subsequently securing the second plurality of sections to provide leg supports.

3. The method as claimed in claim 1 or claim 2 and including the step of applying the temporary support to the arch or the fixture while the leg support arch or the fixture while the leg support arch sections are set.

8. The method as claimed in claim 1 and including the step of securing further monorail sections to the arches as succeeding arches are set.

9. The method as claimed in any preceding claim including the preliminary step of assembling the arch sections in a vertical form on the floor of the passageway and then lifting in the assembled form to a position for transport to the location.

10. Apparatus for use with a method as claimed in any preceding claim and including a monorail suspended from previously set arches in a passageway, a powered unit suspended from the monorail being arranged to move the arch sections along the monorail to the forward position.

11. Apparatus as claimed in claim 10 in which the monorail includes a support platform adapted to receive a fixture supporting the arches, the support platform, being raised and lowered through articulated arms which are hydraulically operated.

12. Apparatus as claimed in claim 10, or claim 11 and including a working platform associated with the monorail, the working platform being hydraulically operated to raise and lower the platform within the passageway.