GB2053129A - Apparatus for transferring fluent solids, liquids or gases to receptacles or pipelines - Google Patents

Abstract

Apparatus, for use in transferring fluent solids, liquids or gases from a source to a receptacle or pipeline, comprises a discharge conduit (12) associated with an inflatable member (15) into which fluid can be introduced to cause it to expand into sealing contact with a mouth of a receptacle (11). The seal prevents escape of undesirable dust and/or fumes whilst allowing a range of sizes of receptacles, not necessarily regular, to be used. An extraction hood (18) exhausts displaced air (17) through a space between a sleeve (13) and the conduit (12). An air adjustment valve (20) is provided in the exhaust system. <IMAGE>

Description

SPECIFICATION Transfer apparatus This invention relates to apparatus for use in transferring material from a source to a receptacle. The apparatus is particularly concerned with the transfer of powdery or granular materials, from a storage silo to transportation containers such as bags and drums. However, the apparatus can equally well be used in the transfer of liquids and gases.

When powder is being transferred from a silo to a container such as a sack or drum, a discharge conduit is usually inserted into the mouth of the container, with an air gap between the container and the conduit. During filling, the air displaced from the container passes out through this gap carrying a part of the powder with it and this powder is almost invariably undesirable. It can cause pollution of the environment around the point-of use, it may be irritating or dangerous to operatives, or in the case of expensive powder it can be a costly waste, in the case of inflammable powder or liquid, there can be a danger of explosion. The use of external clamps to secure the container seldom results in an air-tight seal, and different sizes of container often can not be accommodated. Further, such clamps present the possibility of physical injury to operatives.To provide each and every container with a fitting capable of sealing with the discharge conduit would be prohibitively expensive.

An object of the invention is to provide an improved apparatus for use in transferring material from a source to a receptacle.

Accordingly the invention provides apparatus, for use in transferring material from a source to a receptacle, comprising a discharge conduit associated with an inflatable annulus into which fluid can be introduced to cause it to expand into sealing contact with a mouth of a receptacle. Conveniently the annulus surrounds the discharge conduit.

Preferably the annulus surrounds an end portion of the discharge conduit and can be inflated by means of compressed air to a predetermined degree. It is advantageous if the annulus is resilient to enable it to expand to varying sizes to seal with various sizes of receptacles.

When the material and the conduit so allows, air displaced from the receptacle can flow back along the conduit. However, in most cases an outlet for displaced air, and entrained material is necessary.

This can take the form of a drain conduit, also surrounded by the annulus, and leading to, say a material container above the level of material therein. More usually, however, the outlet for displaced air and entrained material will include a second conduit connected to an exhaust and filtration system. The second conduit can conveniently be defined by the outside of the discharge conduit and the inside of a sleeve surrounding it. The annulus can expand axially of the discharge conduit to seal with a surface around a filling aperture of a tank or the like.

Means for supplying compressed air to the annulus, can comprise an air reservoir selectively connectable, by a souble pole-double throw valve to a supply and the annulus. Thus, normally the reservoir will be connected to the supply and fully charged, whilst the annulus is connected to atmosphere.

Upon actuation of the said valve, via a first control valve, the container is disconnected from the supply and connected to the annulus to inflate it. After a transfer operation is completed, a second control valve iXs actuated, which changes the condition of the dou ble-pol e-dou ble-th row valve to connect the annulus to atmosphere and the reservoir back to the supply for re-charging. Means can be provided for supplying a purging gas, for example an inert gas, to purge air from a receptacle when the possibility of explosion exists.

The invention will be described further, by way of example, with reference to the accompanying drawing, wherein the single figure is a cross-sectional view of a preferred embodiment thereof, it being understood that the following description is illustrative and not limitative of the scope of the invention.

A preferred embodiment of transfer apparatus 10 of the invention is suitable for use in transferring powder from a storage silo (not shown) into sacks or drums for transportation. In the drawing the upper edge of a sidewall 11 of a drum is shown. Afree end of a powder discharge conduit 12 is surrounded by a co-axial cylindrical sleeve 12 of greater diameter than the conduit 12. At the free end of the sleeve an annular first clamp 14 retains in sealing manner one edge portion of an anular C-section rubber or elastomer annulus 15 whose other edge portion is sealed to the sleeve 13 by a second clamp 16 at a position spaced from the first clamp 14.

The space between the sleeve 13 and the outer wall of the conduit 12 serves as a duct to allow passage of displaced air indicated by arrows 17 and connects with an extraction hood 18. There is a gap between the second clamp 16 and the periphery of the hood 18 for a purpose to be described later.

In use, the apparatus is introduced into the mouth of a drum to be filled and the annulus 15 is inflated to expand into sealing contact with the wall 11. Powder can now be fed to the drum, for example by gravity, air displaced from the drum, together with powder entrained thereby, passes up the duct to the extractor hood 18 whence it is drawn by suction to a filtration unit (not shown), for example for recovery.

The gap between the hood 18 and the upper clamp 16 allows compensation air (arrows 19) to be drawn into the exhaust system and prevents the exhaust system from applying too great a suction when powder flow is zero or small. An air adjustment valve 20 is provided in the exhaust system for regulation and can be closed upon container removal to ensure that maximum exhaust flow is encouraged during this period.

After a drum has been filled the annulus 15 is deflated and the filled drum removed.

The supply of air to the annulus 15 is controlled by a mechanism (not shown) which includes an air reservoir of predetermined volume, a main doublepole-double-throw valve, a connection to an air source, and two control valves. In a rest condition the reservoir is full and connected to the supply and the annulus 15 is deflated and connected to atmosphere. To inflate the annulus 15 a first of the control valves is actuated which causes the main valve to dis-connect the reservoir from the source, disconnect the annulus 15 from atmosphere and connect the two together. After a filling operation the second control valve is actuated which causes the main valve to disconnect the annulus 15 and reservoir and connect the former to atmosphere and the latter to the source for refilling.

It will be appreciated that the apparatus of the invention allows powder to be transferred to a receptacle substantially without loss or leakage, the annulus 15 being capable of varying degrees of inflation, determined by the receptacle, to suit receptacles of different sizes and a range of shapes.

For example drums with dented mouths can easily be accommodated by the apparatus of the invention.

Further, the apparatus of the invention leaves the mouths of the receptacle free of dust. This can be very important when plastics bags are involved because heat-sealing is facilitated.

The invention is not limited to the previse details of the foregoing, and variations can be made thereto. For example instead of the described air exhaust system the duct can simply lead to, say a space above the material in, say, a silo. For some materials it could vent to atmosphere by a simple filter. In a few cases, when the material is, say, a very coarse granular material, the duct could be dispensed with altogether, displaced air passing in counter-current up the discharge conduit 12. The apparatus can be used with liquids and gases as well as solids, particularly where the gases, or fumes from the liquid are undesirable. The receptacle can be a tank, tanker, or a pipeline of greater diameter than the discharge conduit. As a further alternative an outer sleeve can carry the annulus for internal expansion into sealing contact with a mouth of a receptacle. If the container is flexible the end of the conduit can enter its mouth and the annulus pressurised to urge the mouth of the receptacle inwards into sealing contact therewith.

The annulus can, if desired, expand axially of the conduit for sealing with a surface around a filling aperture of a receptacle such as a tank of a road tanker or of a machine.

Means can be provided to enable a purging, e.g.

inert, gas to be supplied to the interior of the receptacle to remove air therefrom. This useful when inflammable or explosive powders or liquids are to be transferred.

Many other variations are possible within the scope of the following claims.

Claims (7)

1. Apparatus, for use in transferring material from a source to a receptacle, comprising a discharge conduit associated with an inflatable annulus into which fluid can be introduced to cause it to expand into a sealing contact with a mouth of a receptacle.

2. Apparatus as claimed in claim 1, wherein the annulus surrounds the discharge conduit.

3. Apparatus as claimed in claim 2, wherein the annulus surrounds an end portion of the discharge conduit and can be inflated by means of compressed air.

4. Apparatus as claimed in any preceding claim, wherein the annulus is resilient to enable it to expand to varying sizes to seal with various sizes of receptacles.

5. Apparatus as claimed in any preceding claim, wherein a drain conduit is provided for leading displaced air from the receptacle.

6. Apparatus as claimed in claim 5, wherein the drain conduit leads to an exhaust and filtration system.

7. Transfer apparatus, for use in transferring material from a source to a container, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

7. Apparatus as claimed in claim 5 or 6, wherein the drain conduit is defined by the outer wall of the discharge conduit and surrounding sleeve.

8. Apparatus as claimed in claim 6, wherein the exhaust and filtration system includes an extractor hood.

9. Apparatus as claimed in any preceding claim, wherein means for inflating the annulus comprises a fluid reservoir selectively connectable by a doublepole-double-throw valve to a supply and to the annulus.

10. Apparatus as claimed in claim 1, wherein an outer sleeve connected to the discharge conduit carries the annulus for expansion inwardly against the outer wall of a receptacle.

11. Apparatus as claimed in claim 1, wherein the annulus can expand radially of the discharge conduit to seal with a surface around a filling aperture of a receptacle such as a tank.

12. Apparatus as claimed in any preceding claim and having means whereby a purging gas can be supplied to the interior of the receptacle to remove air therefrom.

13. Apparatus, for use in transferring material from a source to a receptacle, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

New claims or amendments to claims filed on 22.8.80.

Superseded claims 1 to 13 New or amended claims:

1. Transfer apparatus, for use in transferring material from a source into a container, comprising a discharge conduit, an annulus around the conduit and defining, between itself and the conduit, a duct for passage from the container of displaced air, the annulus being inflatable to expand it into sealing contact with the mouth of the container, and an exhaust system connecting with the duct, there being a gap between the duct and the exhaust system to permit air to be drawn into the latter to preventtoo great a suction being applied by the exhaust system.

2. Transfer apparatus as claimed in claim 1, wherein the annulus is resilient to enable itto expand to varying sizes to seal with various sizes of container.

3. Transfer apparatus as claimed in claim 1 or 2, wherein the exhaust system includes an extractor hood.

4. Transfer apparatus as claimed in claim 1, 2 or 3 wherein means for inflating the annulus comprises a fluid reservoir selectively connectable to a supply and to the annulus.

5. Transfer apparatus as claimed in claim 1, wherein an outer sleeve around the discharge conduit carries the annulus.

6. Transfer apparatus as claimed in any preceding claim and having means whereby a purging gas can be supplied to the interior of the container to remove air therefrom.