GB1597339A

GB1597339A - Mounting machines on foundations

Info

Publication number: GB1597339A
Application number: GB5161576A
Authority: GB
Original assignee: Staveley Machine Tools Ltd
Current assignee: Staveley Machine Tools Ltd
Priority date: 1977-12-12
Filing date: 1977-12-12
Publication date: 1981-09-03

Description

(54) MOUNTING MACHINES ON FOUNDATIONS (71) We, STAVELEY MACHINE TOOLS LIMITED, of Highroad Well Works, Halifax in the County of York, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention is concerned with mounting machines on foundations, and it is thought that the method and apparatus of the invention will be particularly useful for the mounting of large machines, and more particularly still, machine tools, which must be accurately levelled if they are to function correctly.

The traditional method of mounting a machine, is to prepare a flat bed of concrete, fit rag bolts into the concrete bed, place the feet of the machine on the bed, over the projecting parts of the rag bolts, and then tighten nuts on to the bolts to nip the feet. This method is inadequate where accuracy of levelness is essential, and especially so with large machines where the foundation is correspondingly large and may not be level.

In a known kind of machine mounting, a foot portion of the machine is sandwiched between an adjustable jack which is in compressiqn betwen the foot portion and the foundation, and a foundation nut secured to a foundation bolt, which is in tension between an anchor position and the nut. (Such a mounting arrangement will be hereinafter referred to as a jack-type mounting).

When using a jack-type mounting, levelness is obtained by adjusting the jacks, after the machine has been allowed to settle on to the jacks. Obviously therefore, it is necessary for the jacks to lift the weight of the machine during the adjusting operation, and this requires considerable effort. One well known way of carrying out the adjustment, is to use a screw-jack, which is turned by fitting a large spanner to the jack, and hitting the spanner with a sledge hammer.

In order to achieve rigidity in the jacktype mounting, it is necessary to provide a predetermined minimum stress in the foundation bolt. This is usually done, by tightening the foundation nut, after the jack has been adjusted to level the machine bed.

The principal object of the present invention is to provide a method of accurately mounting a machine on a foundation, which does not require the same physical effort by the fitter, as that referred to above, when adjusting a screwjack, by means of a spanner and sledge hammer. The invention also comprehends mounting apparatus for machines, which can be used in the method of the invention.

According to one aspect of this invention, in the mounting of a machine on a foundation by means of a jack-type mounting (as defined above), the foundation bolt is pre-stressed, and the weight of the machine taken off the jack, until the jack has been adjusted to its working position, whereupon the machine is allowed to settle on to the jack, the pre-stressing of the foundation bolt being maintained at least until the machine has settled on to the jack.

The pre-stressing of the bolt may be achieved by raising the machine after the bolt has been anchored, and the foundation nut fitted, so that the foot portion of the machine engages with the nut, and stretches the foundation bolt. In one alternative the pre-stressing of the bolt may be achieved by threading the bolt through a foot portion of the machine, fitting the nut to the bolt, and then applying a downward force to the bolt.

In another alternative, the pre-stressing of the foundation bolt may be achieved by securing a stretching device to the upper end of the foundation bolt where it projects above the foundation nut, and pulling the upper portion of the bolt upwardly relatively to a foot portion of the machine.

According to a preferred feature of the invention, a method of mounting a machine on a foundation comprises anchoring the foundation bolt in the foundation, threading the bolt through a foot portion of the machine, securing the foundation nut on the bolt, on the opposite side of the machine foot portion to the foundation, and tightening the nut irito engagement with the foot portion, positioning an adjustable jack between the foundation and the foot portion, raising the machine by means separate from the adjustable jack to stretch the bolt and create a clearance between the foot portion and the jack, adjusting the jack to a datum position where it provides a bearing surface for the foot portion of the machine, and lowering the machine until it rests on the adjustable jack, the datum position being such that in the position of rest of the machine the foundation bolt remains in a stretched condition, to provide a required rigidity of the mounting.

In the preferred method, the machine is raised to stress the foundation bolt by one or more removable jacks positioned temporarily under the machine. These removable jacks may, for example, be hydraulic jacks. It is also preferred that the adjustable jack has a screw connection with a foundation pedestal secured in the foundation with the foundation bolt.

According to another aspect of the invention a machine mounting comprises a pedestal adapted to be secured to a foundation, a jack adjustably mounted on the pedestal, a foundation bolt secured directly to the pedestal and having a screwthreaded portion projecting above the pedestal and a foundation bolt nut for securing on to the foundation bolt.

Preferably the foundation bolt passes through but is independent of the jack. The jack may have a screw-threaded connection with the pedestal.

According to another preferred feature of the invention a part spherical bearing is provided for action between the jack and a foot portion of the machine. This may take the form of a pair of washers, with complimentary part spherical surfaces (one convex and the other concave) for mounting on the jack and below the foot portion of the machine.

The pedestal may comprise a generally cylindrical member, with an annular flange at or near its lower end to provide an asperity for anchoring in the foundation, and an annular boss at or near its upper end, the recess for the jack being formed in this boss. The jack may simply comprise an externally screw-threaded cylinder with a flange at its upper end formed to provide a grip for a rotating tool such as a spanner or tommy bar.

The construction of a mounting for a machine tool, and its method of use, together with certain alternative constructions, all in accordance with the invention, will now be described by way of example only, with reference to the drawings accompanying the Provisional Specification, in which: Figure 1 is a vertical section through the mounting, Figure 2 is an end view in the direction of arrow II in Figure 1, Figure 3 is a plan view of the mounting, Figure 4 is an enlarged detail of part of the arrangement shown in Figure 1 Figure 5 is a part sectional view through an alternative stretching arrangement, and Figure 6 is a section on the line VI-VI in Figure 5.

The mounting which is illustrated in Figures 1 to 4 of the drawings, is particularly intended for use in the mounting of large and heavy machine tools, such as horizontal boring machines, wherein it is difficult to obtain a completely level foundation, and where the machine bed itself, can be subject to deflections due to inherent loads. Part of the machine tool bed is indicated in Figures 1 and 4 at 10, and it will be appreciated that this is only a small part of the bed, in the vicinity of a mounting arrangement. In practice, there will be a number of these mounting arrangements at spaced positions around the bed of the machine, but as they are identical with each other, it is only necessary to describe one mounting arrangement in detail. It is to be noted, that a recess 12 is formed in the bed 10 in such a manner as to provide a foot portion 14 of the bed below the recess 12.

Part of the foundation is indicated at 16, and a hole 18 is formed in the foundation at each mounting position. The actual mounting includes a pedestal 20, which generally takes the form of a cast iron cylinder, having a part conical annular asperity 22 at its lower end, and a substantially annular boss 24 at its upper end, there being a pair of diametrically opposed lugs 25 on the boss 24. The lugs 25 have flat top and bottom faces.

As is apparent from Figure 1, the pedestal 20 is eventually fitted into the hole 18 in the foundation, and at a subsequent stage in mounting the machine, grouting is poured into the hole 18, so that the pedestal 20 becomes embedded in the foundation, the annular asperity 22 at the lower end of the pedestal providing a means for anchoring the pedestal in the foundation.

The lower end of the pedestal 20 is bored and internally screw-threaded, to receive the lower end of a steel foundation bolt 26, which by virtue of its screw-threaded engagement with the lower end of the pedestal, is secured to that pedestal. It will be observed that the foundation bolt 26 passes upwardly through a large clearance hole 27 in the pedestal, and projects a considerable distance above the top of the pedestal.

The large boss 24 at the upper end of the pedestal is counter-bored at 28, and internally screw-threaded, to receive a jack 30, which is made of steel, and which generally takes the form of a cylinder, having an external screw thread for engagement in the screw-threaded bore 28 in the pedestal. The jack 30 is of generous proportions, and the screw-threaded connection with the pedestal, is several inches long, because in the completed mounting arrangement, there will be a considerable load transmitted through the jack, to the pedestal. There is a clearance hole 32 passing vertically through the centre of the jack 30, so that the foundation bolt 26 can pass through the jack, without being connected to it.At its upper end, the jack 30 is formed with an annular flange 34 which has four notches 36 formed in its periphery at equi-angularly spaced positions, and four holes 37 arranged at positions spaced between the notches. The purpose of the notches 36 is to receive pegs positioned diametrically opposite each other, in a Cspanner and the holes 37 provide for turning the jack 30 by means of a tommy bar.

A two part spherical bearing 42 is also provided, and this takes the form of a pair of washers 44 and 46, the washer 44 having a concave upper surface, and the washer 46 having a correspondingly convex lower surface, the two part spherical surfaces engaging with each other as indicated in Figures 1 and 4, when the two washers are assembled on top of the jack.

The mounting apparatus is completed by a foundation nut 48, which is engageable on a screw-threaded upper portion 50 of the foundation bolt 26, and a thick washer 49 acting between the nut 48 and the top side of the foot portion 14. A rubber "O"-ring 51 is fitted around the portion of the foundation bolt 26, which eventually enters a mounting clearance hole 53, formed in the foot portion 14 of the machine.

When the machine tool is to be mounted on a foundation, the hole 18 is first formed in the foundation, and the entire assembly of the mounting arrangement is loosely secured to the foot portion 14 of the bed 10, by first screwing the lower end of the foundation bolt 26 into the pedestal 20, then threading the bolt 26 through the jack 30, and screwing the jack into the upper end of the pedestal, then passing the bolt through the spherical bearing 42, and through the clearance hole 53 in the foot portion 14, and through the washer 49, and finally screwing the nut 48 on to the screw-threaded upper portion of the foundation bolt.In this loosely assembled condition of the mounting arrangzment, the pedestal, together with the jack 30 and the spherical bearing, are suspended from the foot portion of the machine, and the "O"-ring 51 roughly centralises the foundation bolt 26 in the clearance hole 53.

At this stage, it is necessary to pre-stress the foundation bolt, to ensure rigidity in the final assembly, and this is done by placing a small hydraulic jack 56, 58 on each of the lugs 25 of the pedestal, under part of the machine bed, and then operating the jacks so that their respective rams are extended into engagement with the machine. Further projection of the rams under the action of the applied hydraulic pressure causes the pedestal 20 to move downwardly relatively to the machine, and since the lower end of the foundation bolt is secured to the pedestal, this has the effect of stretching the foundation bolt, and pre-stressing the bolt in tension. The pre-stressing is carried out, to an extent somewhat greater than the minimum stress required in the bolt, to achieve rigidity of the finished mounting.

After this initial pre-stressing of the foundation bolt, the jack 30 is screwed upwardly relatively to the pedestal 20, so as to tighten the spherical bearing 42 against the underside of the foot portion 14. The hydraulic jacks can then have their rams retracted, and these jacks are then removed for use on another pedestal. However, despite the fact that the rams are retracted, the tensile stress remains in the bolt 26, between the nut 48 and the position where the bolt is secured to the lower end of the pedestal.

The machine tool is then lowered into position by means of a crane (not shown) until the pedestal 20 lies almost completely within the hole 18, although as indicated in Figures 1 and 2, part of the pedestal projects above the top of the hole 18. The machine bed is then rough-levelled, by means of adjustable wedge blocks palced at the Airy points under the machine. The adjustable wedge blocks are of the type which employ screw operated wedges, and are expensive to employ as mountings, but the present invention only requires the temporary use of these adjustable mounting blocks during the mounting operation.

When the machine bed is level within say a few thousandths of an inch grouting is poured into the hole 18, and allowed to set, so that the pedestal becomes firmly embedded within the foundation in an upright position. In this condition, the machine is supported in a substantially level position, on the foundation. Because the foundation itself may not be level, or because of deflections which take place in the machine bed during the rough levelling operation, at some mounting positions, gaps may appear between the bearing 42 and the underside of the bed. However, these gaps will not be large, perhaps in the order of 0.002 inch.

The wedge blocks are then removed, allowing the bed to settle on to the mounting assemblies, so that the weight of the machine is then transmitted through the jack 30 and the pedestal 20. This results in slight compression of the pedestal and jack.

The hydraulic jacks 56 and 58 are then replaced on the lugs 25 and again operated, to project their respective rams, so that upward pressure is applied against the underside of the bed 10. This has the result of lifting the bed 10 from engagement with the top washer 46 of the spherical bearing 42, thereby ensuring that there is no downward pressure applied by the machine on the jack 30, and at the same time, the foundation bolt 26 is further stretched between its position of securing to the lower end of the pedestal, and the position where the nut 48 is fastened on to the bolt. The actual gap which appears between the underside of the foot portion 14 and the top surface of the upper washer 46 can be quite small, perhaps in the order of 0.010 inch.

Hence, it may not be necessary to project the rams of the hydraulic jacks by any considerable distance during this second operation of the jacks.

The jack 30 is then rotated manually, using either a C-spanner or a tommy bar, so that its upper surface which carries the spherical bearing 42, arrives at a datum position, which is required to accurately locate the portion of the machine tool bed in the vicinity of the mounting. It will be appreciated that it is relatively easy to turn the jack 30, to effect this adjustment, because at that stage, no vertical load is applied to the jack. Furthermore, since the screw-threaded connection with the pedestal will have a relatively fine pitch, it is quite easy to obtain very accurate adjustment of the jack.The effect of turning the jack into its datum position is of course to reduce the gap which has appeared between the underside of the foot portion 14 and the top surface of the upper washer 46, but if the foundation bolt has been correctly stretched, the gap will not altogether disappear. In fact, if the spherical bearing does come into engagement with the underside of the foot portion 14, making it difficult to turn the jack, the fitter will then know that there has been insufficient stretching of the foundation bolt, and it will be necessary to operate the hydraulic jacks 56 and 58 again, so as to release the downward pressure on the jack 30, to allow the adjustment of that jack to be completed manually.

When the jack has been correctly positioned, the rams of the hydraulic jacks 56 and 58 are retracted, allowing the bed of the machine to settle down on to the spherical bearing 42, following which, the hydraulic jacks 56 and 58 are removed altogether. During this settling operation, the washers 44 and 46 may move relatively to each other, to allow the bed to sit flat on the top surface of the upper washer 46.

As the machine tool settles down on to the spherical bearing, a compressive force is applied to the jack 30, between the spherical bearing and its screwed connections with the pedestal 20, so that there is then provided a correct jack-type mounting arrangement, in which the jack 30 is placed in compression between the pedestal 20 and the underside of the foot portion 14, and the foundation bolt 26 is placed in tension between its position of engagement with the pedestal, and the foundation bolt nut 48.

Providing the datum position of the jack has been correctly chosen, the foundation bolt will still be stressed beyond the predetermined minimum stress, to achieve a rigid mounting. In this connection, it will be appreciated, that there is always a minimum stress in a foundation bolt, below which the bolt would not be effective to prevent the part of the machine tool bed in the vicinity of that bolt from rising under applied loads. It is a feature of the present invention, that one ensures that this minimum stress is always attained in the foundation bolt, so that the bolt remains stressed at least until the machine has settled on the jack 30, and as a means of achieving this, the hydraulic jacks 56 and 58 are initially operated to overstress the foundation bolt 26.

In some instances, it might be possible to avoid the first foundation bolt stretching operation, which it will be recalled, took place before the pedestal 20 was grouted into the hole 18 in the foundation. In other words, after the mounting assembly has been suspended from the foot portion 14 of the machine tool, the machine is lowered, to lower the pedestal 20 into the hole 18, and then the machine is rough levelled using the adjustable foundation blocks. Grouting is then poured into the hole 18, and allowed to set, so that the pedestal becomes firmly embedded in the foundation. Only at this stage are the hydraulic jacks 56 and 58 introduced between the lugs 25 and the underside of the machine. The jacks 56 and 58 are then operated to lift the machine to produce the necessary clearance between the spherical bearing 42 and the underside of the foot portion 14, and care must be taken to ensure that the stretching of the foundation bolt 26 which occurs at this juncture, produces a greater stress than the minimum stress required in the finished mounting. The jack 30 is then adjusted to the datum position as previously described, and the machine allowed to settle on to the spherical bearings, and the hydraulic jacks 56 and 58 removed.

This method of mounting may not be feasible in some circumstances, wherein the hydraulic jacks would have to move through differing distances, at different points on the machine bed, owing to discrepancies in the foundation and/or deflections of the bed itself. This is because it might not be practicable to obtain adequate stressing of the foundation bolt 26 at every mounting position.

An alternative method of achieving the pre-stressing of the foundation bolt is Illustrated in Figures 5 and 6 of the drawings, wherein only the upper screwed portion 50 of the bolt is shown, the arrangement of the pedestal, jack and spherical bearing being identical with that illustrated in Figures 1 to 4. Also there is a thick washer 49 similar to that shown in Figures 1 to 4, and a foundation bolt nut 60, which has the same function as the nut 48, but which is provided with holes 62, to receive a tommy bar 64.

A steel spacer member 66 generally of cylindrical formation fits over the upper portion 50 of the foundation bolt, and over the nut 60, and stands on the washer 49, as illustrated in Figure 5. A lower part of the cylindrical spacer member 66 is cut away as indicated at 68 in Figure 6, to allow the tommy bar 64 to be inserted into one of the holes 62 in the nut 60, so that it is possible to carry out turning of the nut 60 by using the tommy bar, even when the spacer member 66 is in position.

A hydraulic jack 70 is placed on the spacer member 66, and has a ram 72, which at its lower end carries a collet 74 screwthreaded internally, for engagement with the screw-threaded upper end of the foundation bolt 26. As shown in Figure 5 the collet 74 is secured on to the upper end of the foundation bolt, so as to obtain a good purchase thereon, and is free to move through a clearance hole 76 formed in the upper end of the spacer member 66.

The spacer member 66 and the hydraulic jack 70 are fitted on to the mounting assembly, after the latter has been suspended from the foot portion 14 of the machine tool, and before the pedestal 20 has been grouted into the hole 18 in the foundation. The hydraulic jack 70 is operated to retract its ram 72 upwardly, and this has the effect of pulling on the upper end of the foundation bolt. This in turn causes the spherical bearing 42 to be pressed against the underside of the foot portion 14, and as the bolt is further stretched, the nut 60 is turned by use of the tommy bar 64, to tighten the nut, taking up any slack. Thus, when the pressure is released in the hydraulic jack 70, and the jack is disconnected from the foundation bolt, the bolt remains in the pre-stressed condition between the spherical bearing 42, and the nut 60.

As a further alternative method of prestressing the foundation bolt, a special flanged adapter may be provided, having a screw-threaded bore, for engagement with the upper projecting end 50 of the foundation bolt. This adapter can be screwed on to the foundation bolt, leaving its flange projecting beyond the periphery of the washer 49, and small hydraulic jacks, similar to the jacks 56 and 58, can then be fitted between the top surface of the foot portion 14, and the underside of the flange.

When these jacks are operated, they will stretch the upper portion of the bolt, in a similar fashion to the stretching obtained by use of the jack 70 illustrated in Figure 5.

WHAT WE CLAIM IS: 1. A method of mounting a machine on a foundation by means of a jack-type mounting (as herein defined), in which the foundation bolt is pre-stressed, and the weight of the machine taken ofT the jack, until the jack has been adjusted to its working position, whereupon the machine is allowed to settle on to the jack, the prestressing of the foundation bolt being maintained at least until the machine has settled on to the jack.

2. A method of mounting a machine as claimed in Claim 1, in which the prestressing of the foundation bolt is achieved by raising the machine after the bolt has been anchored, and the foundation nut fitted, so that the foot portion of the machine engages with the nut, and stretches the foundation bolt.

3. A method of mounting a machine as claimed in Claim 1, in which the prestressing of the foundation bolt is achieved by threading the bolt through a foot portion of the machine, fitting the nut on to the bolt, and then applying a downward force to the bolt.

4. A method of mounting a machine as claimed in Claim 1, in which the prestressing of the foundation bolt is achieved by securing a stretching device to the upper end of the foundation bolt where it projects above the foundation nut, and pulling the upper portion of the bolt upwardly relatively to a foot portion of the machine.

5. A method of mounting a machine as claimed in Claim 1, comprising the steps of anchoring the foundation bolt in the foundation, threading the bolt through a foot portion of the machine, securing the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. minimum stress required in the finished mounting. The jack 30 is then adjusted to the datum position as previously described, and the machine allowed to settle on to the spherical bearings, and the hydraulic jacks 56 and 58 removed. This method of mounting may not be feasible in some circumstances, wherein the hydraulic jacks would have to move through differing distances, at different points on the machine bed, owing to discrepancies in the foundation and/or deflections of the bed itself. This is because it might not be practicable to obtain adequate stressing of the foundation bolt 26 at every mounting position. An alternative method of achieving the pre-stressing of the foundation bolt is Illustrated in Figures 5 and 6 of the drawings, wherein only the upper screwed portion 50 of the bolt is shown, the arrangement of the pedestal, jack and spherical bearing being identical with that illustrated in Figures 1 to 4. Also there is a thick washer 49 similar to that shown in Figures 1 to 4, and a foundation bolt nut 60, which has the same function as the nut 48, but which is provided with holes 62, to receive a tommy bar 64. A steel spacer member 66 generally of cylindrical formation fits over the upper portion 50 of the foundation bolt, and over the nut 60, and stands on the washer 49, as illustrated in Figure 5. A lower part of the cylindrical spacer member 66 is cut away as indicated at 68 in Figure 6, to allow the tommy bar 64 to be inserted into one of the holes 62 in the nut 60, so that it is possible to carry out turning of the nut 60 by using the tommy bar, even when the spacer member 66 is in position. A hydraulic jack 70 is placed on the spacer member 66, and has a ram 72, which at its lower end carries a collet 74 screwthreaded internally, for engagement with the screw-threaded upper end of the foundation bolt 26. As shown in Figure 5 the collet 74 is secured on to the upper end of the foundation bolt, so as to obtain a good purchase thereon, and is free to move through a clearance hole 76 formed in the upper end of the spacer member 66. The spacer member 66 and the hydraulic jack 70 are fitted on to the mounting assembly, after the latter has been suspended from the foot portion 14 of the machine tool, and before the pedestal 20 has been grouted into the hole 18 in the foundation. The hydraulic jack 70 is operated to retract its ram 72 upwardly, and this has the effect of pulling on the upper end of the foundation bolt. This in turn causes the spherical bearing 42 to be pressed against the underside of the foot portion 14, and as the bolt is further stretched, the nut 60 is turned by use of the tommy bar 64, to tighten the nut, taking up any slack. Thus, when the pressure is released in the hydraulic jack 70, and the jack is disconnected from the foundation bolt, the bolt remains in the pre-stressed condition between the spherical bearing 42, and the nut 60. As a further alternative method of prestressing the foundation bolt, a special flanged adapter may be provided, having a screw-threaded bore, for engagement with the upper projecting end 50 of the foundation bolt. This adapter can be screwed on to the foundation bolt, leaving its flange projecting beyond the periphery of the washer 49, and small hydraulic jacks, similar to the jacks 56 and 58, can then be fitted between the top surface of the foot portion 14, and the underside of the flange. When these jacks are operated, they will stretch the upper portion of the bolt, in a similar fashion to the stretching obtained by use of the jack 70 illustrated in Figure 5. WHAT WE CLAIM IS:

1. A method of mounting a machine on a foundation by means of a jack-type mounting (as herein defined), in which the foundation bolt is pre-stressed, and the weight of the machine taken ofT the jack, until the jack has been adjusted to its working position, whereupon the machine is allowed to settle on to the jack, the prestressing of the foundation bolt being maintained at least until the machine has settled on to the jack.

foundation nut on the bolt, on the opposite side of the machine foot portion to the foundation, and tightening the nut into engagement with the foot portion, positioning an adjustable jack between the foundation and the foot portion, raising the machine by means separate from the adjustable jack to stretch the bolt and create a clearance between the foot portion and the jack, adjusting the jack to a datum position where it provides a bearing surface for the foot portion of the machine, and lowering the machine until it rests on the adjustable jack, the datum position being such that in the position of rest of the machine the foundation bolt remains in a stretched condition, to provide a required rigidity of the mounting.

6. A method of mounting a machine as claimed in Claim 2 or Claim 5, in which the machine is raised to stress the foundation bolt by one or more removable jacks positioned temporarily under the machine.

7. A method of mounting a machine as claimed in Claim 6, in which the removable jacks are hydraulic jacks.

8. A method of mounting a machine as claimed in any one of Claims 1 to 7, in which the adjustable jack has a screw connection with a foundation pedestal secured in the foundation with the foundation bolt.

9. A method of mounting a machine on a foundation by means of a jack-type mounting substantially as herein described with reference to the drawings accompanying the Provisional Specification.

10. A machine mounting comprising a pedestal adapted to be secured to a foundation, a jack adjustably mounted on the pedestal, a foundation bolt secured directly to the pedestal and having a screwthreaded portion projecting above the pedestal and a foundation bolt nut for securing on to the foundation bolt.

11. A machine mounting as claimed in Claim 10, in which the foundation bolt passes through but is independent of the jack.

12. A machine mounting as claimed in Claim 10 or Claim 11, in which the jack has a screw-threaded connection with the pedestal.

13. A machine mounting as claimed in any one of Claims 10 to 12, in which a part spherical bearing is provided for action between the jack and a foot portion of the machine.

14. A machine mounting as claimed in Claim 13, in which the part spherical bearing takes the form of a pair of washers, with complimentary part spherical surfaces (one convex and the other concave) for mounting on the jack and below the foot portion of the machine.

15. A machine mounting as claimed in any one of Claims 10 to 14, in which the pedestal comprises a generally cylindrical member, with an annular flange at or near its lower end to provide an asperity for anchoring in the foundation, and an annular boss at or near its upper end, a recess for the jack being formed in this boss.

16. A machine mounting as claimed in any one of Claims 10 to 15, in which the jack comprises an externally screw-threaded cylinder with a flange at its upper end formed to provide a grip for a rotating tool such as a spanner or tommy bar.

17. A machine mounting constructed and arranged substantially as herein described with reference to the drawings accompanying the Provisional Specification.