GB2072351A - Weight Testing Apparatus - Google Patents

Abstract

A weight-testing bag 10 comprises a flexible envelope 11 of liquid-impervious material having an inlet 12 and an outlet 13, means for suspending the bag from a support, and valve means 21, 22, 23 associated with the outlet operable to regulate the amount of liquid discharged from the envelope through the outlet. <IMAGE>

Description

SPECIFICATION Improvements in and Relating to Weight Testing Apparatus The present invention relates to weight testing apparatus and particularly to apparatus for testing the lifting strength of hoists, winches and similar lifting devices.

In our copending U. K. Patent Application No.

79.08069 we describe a weight testing apparatus which comprises a weight testing bag having a flexible envelope of liquid impervious material, a liquid inlet and a liquid outlet and means for suspending the bag from a support.

The apparatus so described obviates or substantially reduces the problems inherent in transporting and storing bulky and heavy weights since the bag is relatively light but can provide substantial weight when filled up and can be folded or rolled up after emptying and stored in a compact form. The bag, when needed at any particular site, is easily transportable by air, for instance by helicopter, to an oil rig which is moored at sea.

The outlet in the bag described in U. K. Patent Application No. 79.08069 is provided by an aperture located at the bottom of the envelope, the outlet leading to a flexible outlet tube. The flexible outlet tube is of such length that it can be raised and attached to the side of the envelope by a strap near the top of the envelope where it remains while the bag is in use and containing water and during the period when water is introduced into the bag.

The bag is emptied by releasing the outlet tube and allowing it to fall away from the upper end of the bag so that the bag is emptied under gravity.

When not in use the outlet tubeis hooked up to the strap with which the bag is provided and this together with the outlet tube itself forms a bulky external appendage. In the case where several bags are to be supported on a single shackle the tube and strap form an obstruction interfering with other bags and generally increasing the bulk volume of the bags to such an extent that relatively few bags can safely be supported on the shackle. It is therefore an object of the present invention to provide a weight testing bag which is free of the external appendages described above.

According therefore to one aspect of the present invention a weight testing bag is provided, the bag comprising a flexible envelope of liquid impervious material, a liquid inlet, means for suspending the bag from a support, a liquid outlet and valve means associated with the outlet and operable to regulate the amount of liquid discharged from the envelope through the outlet.

Preferably means external of the bag communicate with and are adapted to operate the valve.

Suitably the outlet is provided by the lower open end of a conduit joined in fluid sealed relationship to the bottom of the envelope and extending upwardly to a point adjacent the upper end of the envelope, the conduit wall being apertured adjacent its lower end to provide communication between the liquid in the envelope and the outlet, the valve means being operable to open and close the apertured wall for the retention and removal respectively of liquid in the envelope.

Conveniently the valve means comprises a sleeve slidable on the conduit and resiliently biassed to move to a position in which the apertured wall is normally closed.

Preferably the sleeve is biassed towards the lower end of the conduit.

Suitably the sleeve is connected to elongate means extending upwardly and outwardly from the envelope to enable the sleeve to be moved against the bias to open the conduit wall when the elongate means is partially withdrawn from the envelope.

Conveniently the conduit has an upper portion which is flexible and a lower portion which is rigid and on which the valve sleeve is mounted.

An embodiment of the invention will now be particularly described with reference to the accompanying drawings, in which: Figure 1 is a vertical section through a weight testing bag in accordance with the present invention; and Figure 2 is an elevation of the bag shown in Figure 1.

Referring to Figure 1, a weight testing bag is indicated generally at 10. The weight testing bag 10 comprises a flexible envelope 11 for containing liquid, the envelope being generally pear shaped and made from a fluid impervious material such as reinforced polyvinyl chloride or neoprene. The envelope 11 is open topped at 1 2 and has an outlet 13 provided by the lower open end of a conduit indicated generally at 14 having a lower portion in the shape of a cylindrical metal pipe 15.

The pipe 1 5 extends upwardly from the bottom of the bag to a point situated about one third of the way along the bag vertical length. The pipe 1 5 is welded at its lower end within a cylindrical neck 1 6 of a flanged member 17. The annular flange 1 8 of member 1 7 is slightly dish shaped so as to conform to the curvature of the bottom of envelope 11. The flanged member 1 7 is clamped to the bag skin by means of a clamping ring 19 also dished in conformity with the curvature of flange 18 of member 17.The flange 18 of member 1 7 and the ring 19 are also provided with apertures which when aligned enable the ring flange 1 8 to be clamped to the ring 19 with the bag skin located therebetween by meansof a nut and bolt assembly 20. The bag skin is of course also provided with an alignable aperture (not shown) to permit passage therethrough of the bolt shank.

The wall of the pipe 15 is provided with several apertures including two diametrically opposed pairs 21 of apertures (only one pair shown in Figure 1), the apertures 21 being arranged vertically, and two solitary diametrically opposed apertures 22 disposed at right angles to the opposed pairs of apertures 21.

Mounted concentrically on the pipe 1 5 for vertical sliding movement thereon is a valve means in the form of a cylindrical sleeve 23. The sleeve 23 is dimensioned so that upon vertical movement it can cover and uncover the apertures 21 and 22 in the wall of pipe 15 so as to prevent and permit respectively the discharge of liquid 24 held within the envelope 11.

The sleeve 23 is provided with a pair of diametrically opposed lugs 25 projecting radially from the outer surface of sleeve 23 each lug 25 having a reduced diameter portion 26 to which is secured one end of a return spring 27. The other end of each return spring 27 is secured to the upper surface of the flange 18 of member 1 7.

The return springs 27 cause the sleeve 23 to be biassed downwards, that is, to the position in which the sleeve 23 covers apertures 21 and 22 to prevent the discharge of liquid 24 from the envelope 11. A lanyard or rope 28 is secured to one of the lugs 25. The lanyard 28 extends vertically upwards within the bag 12 towards and through the opening 13 in the envelope 11. The lanyard 28 passes over a pulley 29 located on a boss 30 at the top of bag 12 and hangs down by the side of the bag 12. Pulling the end of the lanyard 28 causes that portion within the bag to move upwardly together with sleeve 23 which slides against its spring bias so as to uncover the apertures 21 and 22.By varying the amount by which the lanyard is pulled up, the extent of vertical movement of sleeve 23 can be varied and the number of apertures 22 uncovered or the degree to which the apertures are uncovered can be controlled as to control the liquid discharge rate from the envelope 11. Upon release of the lanyard the effect of gravity and the bias of springs 27 causes the sleeve 23 to slide downwardly automatically to cover the apertures 21 and 22.

An upper conduit portion in the form of a flexible tube 31 is sleeved on the pipe 1 5 to which the tube 31 is connected and extends upwardly to a point adjacent the upper end of the envelope 11. A load carrying cable 32 extends through the envelope 11 from top to bottom by way of conduit 14. The upper end of the cable 32 terminates in a hook 33 which can easily be attached to a hook or eye 34 which is integral with the support boss 30 located at the apex of the bag 10. The lower end of the cable 32 terminates in an eye 35 which enables a second bag to be suspended below the first bag. The cable 32 is sealed from the contents of the bag at all times since the upper end of the conduit 14 (formed by tube 31) extends nearly to the upper end of the bag.

Referring to Figure 2 the bag envelope 11 is supported by a plurality of strengthening straps 36 made of webbing or any other similar material.

The straps 34 extend from the bottom of the envelope 11 upwardly through sleeves 37 which are attached to the outer surface of the envelope 11. Each strap terminates in an eye 38 which is attached to a shackle 39 which is itself attached to the support boss 30 previously mentioned. The boss 30 has an upwardly extending hook 40 which enables the bag to be easily suspended from a piece of apparatus to be weight tested.

The hook may alternatively be replaced by a conventional-shackle arrangement if desired.

In use, the bag in its unfilled condition can be attached to a winch or other piece of apparatus to be weight tested by means of the hook 40. The valve sleeve 23 is then in its lowermost spring biassed position where apertures 21 and 22 are covered. The bag can then be filled with water or any other liquid through the open top of the, envelope 11. The capacity of the bag will be known and it can be filled to an extent sufficient to provide the required weight test. When the test has been completed, the bag can be quickly and easily emptied by sliding sleeve 23 upwards to uncover the apertures 21 and 22 so that liquid discharges from the bag outlet 1 3 via apertures 21 and 22 under gravity.Alternatively, where a lower bag weight is required for testing another piece of equipment, a measured quantity of liquid can be discharged by regulating the opening and closing of the pipe apertures 21 and 22 until the bag reaches the required weight and the bag can be transported to test the new equipment. When the bag has been emptied after use it can be removed from the apparatus being tested, folded and transported to its next site of use. The provision of the flexible tube 31 enables the bag to be folded into a more compact form than that shown in U.K. Patent Application No. 79.08069 since tube 31 will itself fold into a compact form.

It will be appreciated that the required diminished bag weight can be readily and easily attained by suitable control of liquid discharge.

Furthermore since the discharge of liquid is so controllable the bag can be emptied in an orderly fashion at any desired location.

While not described it will be appreciated that the bags described above can be suspended from any of the hooks, frames or shackles described in U. K. Patent application No. 79.08069 and used in the manner described in that application.

Because it is free of the external tube and strap appendages present in the bags described in U. K.

Patent Application No. 79.08069, the bag of the present invention is more streamlined and less bulky than those bags and accordingly the bags of the present invention can be supported simply and safely from any selected hook, frame or shackle.

In order to minimise the weight of the apparatus and to resist oxidation, the metal components may be made as far as possible from duralumin so as to provide a rust resistant extremely lightweight construction in relation to the weight or mass provided when tha bag or bags are filled to the required extent.

Claims (12)

Claims

1. A weight testing bag comprising a flexible envelope of liquid impervious material, a liquid inlet, means for suspending the bag from a support, a liquid outlet and valve means associated with the outlet and operable to regulate the amount of liquid discharged from the envelope through the outlet.

2. A bag as claimed in claim 1 in which means external of the bag communicate with and are adapted to operate the valve.

3. A bag as claimed in claim 1 or claim 2 in which the outlet is provided by the lower open end of a conduit joined in fluid sealed relationship to the bottom of the envelope and extending upwardly to a point adjacent the upper end of the envelope, the conduit wall being apertured adjacent its lower end to provide communication between the liquid in the envelope and the outlet, the valve means being operable to open and close the apertured wall for the retention and removal respectively of liquid in the envelope.

4. A bag as claimed in claim 3 in which the valve means comprises a sleeve slidable on the conduit and resilient biassed to move to a position in which the apertured wall is normally closed.

5. A bag as claimed in claim 4 in which the sleeve is biassed towards the lower end of the conduit.

6. A bag as claimed in claim 4 or claim 5 in which the sleeve is connected to elongate means extending upwardly and outwardly from the envelope to enable the sleeve to be moved against the bias to open the conduit wall when the elongate means is partially withdrawn from the envelope.

7. A bag as claimed in any of claims 3 to 6 in which the conduit has an upper portion which is flexible and a lower portion which is rigid and on which the valve sleeve is mounted.

8. A bag as claimed in any of claims 3 to 7 in which the bag includes a load carrying cable which extends through the flexible envelope from top to bottom through the conduit, the lower end of the cable being located outside and below the flexible envelope and carrying means for suspending another bag therefrom, the upper end of the cable having means for attachment to a support.

9. A bag as claimed in any of the preceding claims in which the bag includes a plurality of flexible strengthening elements on the outside of the flexible envelope extending from the bottom of the envelope and each having means for attachment to the support.

10. A bag as claimed in claim 9 in which each of the strengthening elements is attached to a load carrying boss.

11. A bag as claimed in any preceding claim in which the flexible envelope is generally pear shaped and open topped.

12. A weight testing bag substantialiy as hereinbefore described with reference to Figures 1 and 2.