GB2230807A

GB2230807A - Mobile drilling rig

Info

Publication number: GB2230807A
Application number: GB9009211A
Authority: GB
Inventors: Grenville James David Thomas
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-04-25
Filing date: 1990-04-24
Publication date: 1990-10-31
Also published as: KR920700343A; GB8909389D0; GB9009211D0; AU5444890A; ZA903156B; WO1990012948A1

Abstract

A mobile drilling rig (1), comprises a wheeled chassis (2), a mounting means (11) for a drilling rig (10) located at a front part (3) of the chassis (2), the mounting means (11) comprising a pair of spaced-apart members (12) rotatably supporting a pair of trunnions (16) extending from opposite sides of a support cradle (17) providing trapping means (23) for engaging slide flanges of a drilling mast (25), with the cradle (17), and hence the mast (25), being rotatable, about the trunnions (16), under the control of a double-acting hydraulic ram (41) connected between the cradle (17) and the front chassis part (3), between an upright or angled, drilling position, and a storage/transportation position, and with the mast (25) being slidably advanceable with respect to the cradle (17), to its drilling position, and slidably retractable with respect to the cradle (17), to its storage/transportation position, by a double-acting hydraulic ram (40) connected between the cradle (17) and the mast (25), a hydraulic motor (29) mounted on a carriage (30) which is also slidably trapped to the mast (25), with the motor (29) being adapted, in use, to drive a drill rod forming part of a drill string, and with means (31 - 33) to advance the carriage (30) along the mast (25), in a drilling direction, and to retract the carriage (30) along the mast (25) for insertion of a fresh drill rod, with a reversal of this procedure to retract a drill string.

Description

MOBILE DRILLING RIG This invention relates to a mobile drilling rig e.g.

for site investigattion drilling, core drilling etc.

Mobile drilling rigs are known comprising a wheeled or tracked vehicle. Known constructions are how ever of substantial dimensions which restricts their use. For instance they can rarely be used for drilling inside a building. On the other hand, portable drilling rigs are known, but of limited size and hence capacity, as to what weight and dimension can be reasonably be man-handled.

According to the present invention, there is provided a mobile drilling rig, comprising a wheeled chassis, a mounting means for a drilling rig located at one end of the chassis, the mounting means comprising a pair of spaced-apart members rotatably supporting a pair of tunnions extending from opposite sides of a support cradle providing trapping means for engaging slide flanges of a drilling mast, with the cradle, and hence the mast, being rotatable, about the trunnions, under the control of a double-acting hydraulic ram connected between the cradle and the chassis, between an upright or a n g 1 e d , d r i 1 1 i n g po s i t i o n, and a storage/transportation position, and with the mast being slidably advanceable with respect to the cradle, to its drilling position, and slidably retractable with respect to the cradle, to its storage/transportation position, by a double-acting hydraulic hydraulic ram connected between the cradle and the mast, an hydraulic motor mounted on a carriage which is also slidably trapped to the mast, with the motor being adapted, in use, to a drill rod forming part of a drill string, and with means to advance the carriage along the mast, in a drilling direction, and to retract the carriage along the mast for insertion of a fresh drill rod, with a reversal of this procedure to retract a drill string.

Although the wheeled chassis could be constituted by a trailer or a self-propelled vehicle such as a lorry, with respectively a separate hydraulic power pack, or an hydraulic pump drivable by-the lorry engine, the chassis is preferably constituted by a conventional dump truck chassis, providing a relatively short wheelbase for optimum manoeuverability and four wheel drive for difficult terrain, a dump truck chassis conventionally having a diesel engine and frequently having an hydraulic pump for ancillaries such as power steering, dump bucket activation etc, with the engine located'at the opposite end of the chassis to the mounting means, with a driving seat and associated steering wheel and controls located mid-way of the chassis.

Thus, for a conventional, two-part dump truck chassis, with the two parts hinged together about a vertical axis pivot pin, with a double-acting steering ram between the two points at each side of the pivot pin, the rear part conveniently carries the engine, drivers seat and driving controls such as a steering wheel, while the front part carries the mast and its ancillaries.

Preferably, the means to advance and retract the carriage along the mast is a double-acting hydraulic ram, with associated wire ropes and return pullies.

Conveniently, the pair of spaced-apart members may comprise upright columns, each carrying at their upper ends a bearing block. In detail, the bearing block may be located in a rebate and secured by four retaining bolts, while each trunnion may be formed at one end of a shaft to which are attached a plurality e.g., four, of rectangular support plates for location in a rectangular, hollow section support tube.

The support tube preferably extends across the underside of the support cradle, which is preferably a fabrication. In detail, the support cradle may comprise a planar, elongate slide bed, with inverted "Ln-section trapping strips secured e.g. by bolts, along each opposite longitudinal edge of the bed, preferably with wear pads along the underside of the strips.

The mast may be supportable at its lower end, when advanced to its drilling position, by a pair of spaced-apart, freely rotatable rollers. These may be carried by a transverse beam extending across the vehicle chassis, beneath the upright columns.

Apart from carrying a reservoir for hydraulic fluid the chassis could carry a water tank and a water pump if a supply of pressurised water is required to a rotary coupling and thence into the drill string for debris flushing, but if air hammer drilling is being effected, the chassis preferably carries a motorised fan for dust collection.

The mounting means end of the chassis is also preferably provided at each side with a pair of ground engaging stabilizers while the other end of the chassis could also be provided with one or a pair of stabilisers, if required. Whilst these could manually extendable and retractable, each preferably incorporates a double-acting hydraulic ram for powered operation. Also preferably located at the mounting means end of the chassis is a control panel and user-operable valve handles for effecting the various operational functitns. Conveniently, the chassis is also provided with an elongate storage cradle for drill rods etc.

The accompanying drawings show by way of example only, various components of the mobile drilling rig in accordance with the invention thus:- Figure 1 is a side elevation of a mobile drilling rig in accordance with the invention mounted on a conventional dump truck chassis; Figure 2 is a front elevation of Figure 1; Figure 3 is an underside perspective view of the support cradle with the cradle rotation ram and the mastadvancing ram; Figure 4 is a top perspective view of the support cradle of Figure 3; Figure 5 is an exploded view of one trunnion and its associated column; Figure 6 is a perspective view of the freely rotatable mast support rollers; Figure 7 shows the rollers of Figure 6 in engagement with the mast; and Figure 8 is a perspective view of a control valve block; In the drawings a mobile drilling rig 1 can be seento comprise a two-part dump truck chassis 2, being a front chassis part 3 and a rear chassis part 4, each part being provided with a pair of driven wheels 5, and the two parts being h'inged together about a vertical axis 6 under the control of a double-acting hydraulic ram (not shown). The rear part 4 is provided with a diesel engine within a casing 7, a drivers seat 8, driver controls 9 and a hydraulic pump (not shown) for various functions, and for clarity all hydraulic hoses have been omitted from Figures 1 and 2.

The front part 3 carries a drilling rig proper 18, via a mounting means 11, the latter comprising a pair of spaced apart members in the form of upright columns 12 welded to the front chassis part 3 and each carrying at their upper ends a bearing block 13 (Figures 2 and 4) located in a rebate 14 and secured by four retaining bolts 15. Each bearing block 13 supports one of a pair of trunnions 16 extending from opposite sides of a support cradle 17. In detail, each trunnion 16 is formed at one end of a shaft 18 to which are attached four rectangular support plates 19 for location in a rectangular, hollow section support tube 2 extending across the underside of the cradle, with welded gussets 21.

The support cradle 17 comprises a planar, elongate slide bed 22, with inverted "L"-section trapping strips 23 secured by bolts passing through aligned bolt holes 24 spaced apart both along the strips 23 and along each opposite longitudinal edge of the bed 22.

The drilling rig lld is generally conventional, comprising a elongate, openwork mast 25, fabricated to rectangular cross-section from four elongate angle section members 26 providing slide flanges to engage under the trapping strips 23. The members 26 are welded at their terminal ends to end plates 27 and are interconnected by bracing struts 28. An hydraulic motor 29 is mounted on a carriage 3 which is slidably trapped to the two upper angle section members 26, and is displaceable along the mast 25 by a double-acting ram 31 and wire rope arrangement 32 extending around spaced apart pulleys 33.An output shaft 34 of the motor 29 is connected via a water inlet coupling 35 to a drive shaft 36 passing through a bearing housing 37, with conventional drill rods (not shown) screwed into the end of the drive shaft 36, in the conventional manner.

An attachment block 38 is welded to the underside of the mast 25 adjacent its upper end, while an attachment block 39 is welded to the underside of the support cradle 17, with a double-acting hydraulic ram 4 connected between the blocks 38 and 39 whereby the mast 25 and hence the drilling rig lld may be slidably advanced and retracted with respect to the support cradle 17, under the control of the operator.Also attached to the block 39 and to the front chassis part 3 is a second double-acting hydraulic ram 41 serving to rotate the support cradle 17, and hence the mast 25 and drilling rig 18 about the trunnions 16, as indicated by arrow 42, between the storage/transportation position illustrated in full line in Figure 1 to the drilling position, one selected drilling position being illustrated in dotted line in Figure 1.

The mast 25 is supportable at its lower end, when rotated to its drilling position and when being advanced with respect to the support cradle 17, by a pair of spaced-apart rollers 43 mounted for free rotation between a pair of support plates 444 welded to a rectangular, hollow section transverse beam 45 of the front chassis part 3.

The hydraulic pump (not shown) supplies pressure fluid to a valve block 46 illustrated in Figure 6 and located behind casing 47 (Figure 1). The block 46 is shown provided with various hydraulic hoses 48 extending to various hydraulic elements of the equipment.

The chassis 2 also carries a reservoir for hydraulic fluid and also a water tank and water pump if a supply of pressurised water is required to be supplied to the drill string for debris flushing while, if an air hammer drilling facility is also required, the chassis 2 is provided with a motorised fan (not shown) for dust collection via a collecting hood 49.

The front chassis part 3 is also provided at each side with a pair of ground engaging stabilisers 5 comprising a double-acting hydraulic ram 51, for powered operation of the stabilisers. Also located at the front chassis part 3 is a control panel 52 and user-operable valve handles 53 for effecting the various operational functions of the equipment, and also an elongate storage cradle 54 for drill rods etc.

Claims

1. A mobile drilling rig, comprising a wheeled chassis, a mounting means for a drilling rig located at one end of the chassis, the mounting means comprising a pair of spaced-apart members rotatably supporting a pair of tunnions extending from opposite sides of a support cradle providing trapping means for engaging slide flanges of a drilling mast, with the cradle, and hence the mast, being rotatable, about the trunnions, under the control of a double-acting hydraulic ram connected between the cradle and the chassis, between an upright or a n g 1 e d, d r i 1 1 i n g p o s i t i o n, and a storage/transportation position, and with the mast being slidably advanceable with respect to the cradle, to its drilling position, and slidably retractable with respect to the cradle, to its storage/transportation position, by a double-acting hydraulic hydraulic ram connected between the cradle and the mast, an hydraulic motor mounted on a carriage which is also slidably trapped to the mast, with the motor being adapted, in use, to drive a drill rod forming part of a drill string, and with means to advance the carriage along the mast, in a drilling direction, and to retract the carriage along the mast for insertion of a fresh drill rod, with a reversal of this-procedure to retract a drill string.

2. A mobile drilling rig as claimed in Claim 1, wherein the wheeled chassis is a trailer with an hydraulic power pack.

3. A mobile drilling rig as claimed in Claim 1, wherein the wheeled chassis is a self-propelled vehicle, with an hydraulic pump drivable from the vehicle engine.

4. A mobile drilling rig as claimed in Claim 3, wherein the chassis is a conventional dump-truck chassis, having a relatively short wheelbase and four wheel drive.

A A mobile drilling rig as claimed in Claim 4, wherein the dump-truck engine is a diesel engine; -while an hydraulic pump serves to power conventionally provided ancillaries, with the engine located at the opposite end of the chassis to the mounting means, with a driving seat and associated steering wheel and controls located mid-way of the chassis.

6. A mobile drilling rig as claimed in Claim 5, wherein with a conventional, two-part dump truck chassis, with the two parts hinged together about a vertical axis pivot pin, with a double-acting steering ram between the two points at each side of the pivot pin, the rear part carries the engine, drivers seat and driving controls such as a steering wheel, while the front part carries the mast and its ancillaries.

7. A mobile drilling rig as claimed in any preceding Claim, wherein the means to advance and retract the carriage along the mast is a double-acting hydraulic ram, with associated wire ropes and return pullies.

8. A mobile drilling rig as claimed in any preceding Claim, wherein the pair of spaced-apart members comprises upright columns, each carrying at their upper ends a bearing block.

9. A mobile drilling rig as claimed in Claim 8, wherein the bearing block is located in a rebate and secured by four retaining bolts, while each trunnion is formed at one end of a shaft to which are attached a plurality of rectangular support plates for location in a rectangular hollow section support tube.

A A mobile drilling rig as claimed in Claim 9, wherein the support tube extends across the underside of the support cradle.

11. A mobile drilling rig as claimed in Claim l, wherein the support cradle is a fabrication.

12. A mobile drilling rig as claimed in Claim 11, wherein the support cradle comprises a planar, elongate slide bed, with inverted "L"-section trapping strips secured along each opposite longitudinal edge of the bed.

13. A mobile drilling rig as claimed in Claim 12, wherein wear pads are provided along the underside of the strips.

14. A mobile drilling rig as claimed in any preceding Claim, wherein the mast is supportable at its lower end, when advanced in its drilling position, by a pair or spaced-apart, freely rotatable rollers.

15. A mobile drilling rig as claimed in Claim 15, wherein the rollers are carried by a transverse beam extening across the vehicle chassis, beneath the upright columns.

16. A mobile drilling rig as claimed in any preceding Claim, wherein apart from carrying a reservoir for hydraulic fluid the chassis carries a water tank and a water pump if a supply of pressurised water is required to a rotary coupling and thence into the drill string for debris flushing.

17. A mobile drilling rig s claimed in any preceding Claim, wherein the chassis also carries a motorised fan for dust collection for air hammer drilling.

18. A mobile drilling rig as claimed in any preceding Claim, wherein the mounting means end of the chassis is also provided at each side with a pair of ground engaging stabilizers.

19. A mobile drilling rig as claimed in Claim 18, wherein the other end of the chassis is provided with one or a pair of stabilisers.

2. A mobile drilling rig as claimed in Claim 19, wherein the sta b il i ser s are manually extendable and retractabl e.

21. A mobile drilling rig as claimed in Claim 19, wherein the stabilisers each incorporate a double-acting hydraulic ram for powered operation.

22. A mobile drilling rig as claimed in any preceding Claim, wherein also located at the mounting means end of the chassis is a control panel and user-operable valve handles for effecting the various operational functions.

23. A mobile drilling rig as claimed in any preceding Claim, wherein the chassis is also provided with an elongate storage cradle for drill rods etc.

24. A mobile drilling rig substantially as hereinbefore described with reference to the accompanying drawings.