WO2001083362A1

WO2001083362A1 - Sump

Info

Publication number: WO2001083362A1
Application number: PCT/GB2001/001844
Authority: WO
Inventors: Christopher J. Cooper
Original assignee: Fibresec Holdings Limited
Priority date: 2000-04-26
Filing date: 2001-04-26
Publication date: 2001-11-08
Also published as: AU5235701A; GB0009997D0

Abstract

A sump for use beneath a filling station petrol pump is disclosed which comprises a generally box-like unit (10) into which petrol lines (30) are led, having a removable top (18) which is sealingly attached thereto. The connections from the inlet pipes (30) and the like to the top are by means of flexible tubing (32) so that the top can be lifted without disconnecting any of the pipelines. The top (18) is fitted with a non-return, e.g. Schraeder, valve (38) or the like so that it can be tested directly for leakage by pulling a vacuum therein. Furthermore, where it is desired that the sump acts as a drain receptacle for any spilled petrol, the lid (18) can be provided with a central well (24) and one or more inspection holes (28) giving access to the sump and acting as drainage ports, which are capable of simply being plugged when testing is required.

Description

SUMP

This invention relates to a sump for a petrol station tank and pump system, and in particular relates to a sealed sump for positioning below a petrol pump.

In many petrol station forecourts petrol tanks are concealed below the ground and pipes connect from the tanks to above-ground electrical pump units for filling vehicles with petrol (gasoline). The petrol tank or tanks will generally have an access chamber or chambers and, in order that these should not allow water in or petrol out, they are usually impervious and can be tested, for example by drawing a vacuum and checking that it is gas-tight.

At one time, the pipes from the tanks to the pumps were simply routed by the most convenient path. However, in order to meet safety requirements in many areas, such pipes now have to go through an outer containment or conduit, i.e. effectively a double walled pipe, which itself must be fluid impervious and may be tested by sealing the end and drawing a vacuum as is known in the art.

The pipes from the tanks usually lead to a sump under the or each petrol pump, which are now normally electrically powered. These sumps have generally been very simple box-like open-top units through which the pipes and electrical connections pass from the ground up into the pumps. However, new regulations require these sumps to be tested also and, currently, there is no simple and reliable way of doing so short of completely removing the petrol pump from on top of it which is an expensive and time consuming operation.

The invention seeks to provide a sump for fitting beneath petrol pumps improved in the above respects.

According to the present invention there is provided a sump for use beneath a filling station petrol pump which comprises a generally box-like unit into which petrol lines are led, having a removable top which is sealingly attached thereto. Preferably, the connections from the inlet pipes and the like to the top are by means of flexible tubing so that the top can be lifted without disconnecting any of the pipelines. Although the sump can be tested from the other end, i.e. from the tank access chamber along the space between the pipe and its protective conduit, it is preferred that the top is fitted with a non-return, e.g. Schraeder, valve or the like so that it can be tested directly for leakage by pulling a vacuum therein.

The sump may be made of any suitable material, such as metal, metal or fibreglass reinforced plastics, or a composite material.

The sump lid conveniently carries studs for holding down the pump. Conveniently the lid may carry more than one set of studs to fit the commonest types of pumps available in petrol stations. In addition, the lid may have pressure inlets capable of receiving the petrol pipes from underneath and having, as known in the art, shear valves connecting from the lid up to the petrol pump. The shear valves are there so that if an accident occurs and the pump is knocked over, the shear valves automatically close cutting off the petrol supply.

Furthermore, where it is desired that the sump acts as a drain receptacle for any spilled petrol, the lid can be provided with a central well and one or more inspection holes giving access to the sump and acting as drainage ports, which are capable of simply being plugged when testing is required.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a diagrammatic perspective view of a sump in accordance with the invention;

Figure 2 is a top plan view of a lid for use with the sump of figure 1 ;

Figure 3 is a perspective view of the lid of figure 2;

Figure 4 is a side elevational view of the lid of figure 2; and Figure 5 is a cross-section through the sump with the lid in place.

Referring to the drawings, a sump generally designated 10 comprises a box-like unit as illustrated, made from fibreglass with angle iron reinforcements, having legs 12. The sump illustrated has three pressure inlet bosses 14 for receiving incoming petrol pipelines. In addition there may be one or more electrical input bosses 16.

A lid or top generally designated 18 fits on the top of the sump 10 and may be bolted securely thereto by means of threaded studs 20. A gasket 22 may be provided between the lid and sump to ensure a fluid tight seal.

The lid 18 includes a central well 24 through which the pressure line inputs pass and to which shear valves may be connected. In addition, as illustrated, there are two inspection holes 28 capable of being plugged.

The pressure inlets 26 are connected to petrol inlet pressure lines 30 by means of flexible piping 32 so that the connection between the petrol line 30 via the flexible pipe 32 to the pressure inlets 26 and shear valves (not shown) to the pump is complete. In the present case three of each are provided to provide three different serving nozzles at the petrol pump for the customer.

The upper portion of the lid 18 carries studs 34 to which the base of the pump may be bolted (figure 5).

In use, the sump is set in concrete beneath the area where the pump is to be sited and is connected via the pressure inlet bosses 14 to the pipes 30 leading from the petrol storage tanks (not shown). The pipes 30 may be in the concentric form referred to earlier herein in which case the outer pipe is open to the interior of the sump and the inner pipe connects to each of the flexible pipes 32 going to the shear valves in the lid 18. Any electrical connections are made and to this end the lid contains electrical sockets 36 as necessary. The use of flexible pipes allows the connections to be made with the lid off. After the necessary connections have been made, the lid 18 is positioned in place on top of the sump with the gasket 22 in between and nuts applied to the studs 20 to tighten it into fluid-sealing relationship. The pump (not shown) may be mounted on the top plate using the studs 34. An inspection hatch present in virtually all pumps allows access into the plate 18. Thus, when it is necessary to test the sump for integrity, it is only necessary for the operative to open the inspection hatch in the pump, and connect a vacuum line to a Schraeder valve 38 and pull a vacuum in order to carry out the necessary test. As is well known in the field, the test involves pulling a vacuum and holding it for a period of time to detect whether any leakage has occurred.

The system may be tested from the other end, i.e. from the access chamber to the tank in which case the whole system of the access chamber, the petrol pipe containment and the sump will be tested as a unit. If any failure occurs it will be necessary to isolate the three parts and test them individually. Hence it is preferred to provide the Schraeder valve 38 or equivalent on the plate 18 to enable testing of the sump on its own.

The sump of the invention provides a simple and economical answer to the necessity to test petrol pump sumps which are currently very difficult to test without a great deal of expense and effort.

Claims

1. A sump for use beneath a filling station petrol pump which comprises a generally box-like unit into which petrol lines are led, having a removable top which is sealingly attached thereto.

2. A sump as claimed in claim 1 wherein the connections from the petrol inlet pipes and the like to the top are by means of flexible tubing so that the top can be lifted without disconnecting any of the pipelines.

3. A sump as claimed in either of claims 1 or 2 wherein the top is fitted with a non-return, e.g. Schraeder, valve or the like so that it can be tested directly for leakage by pulling a vacuum therein.

4. A sump as claimed in any of claims which is made from metal, metal and/or fibreglass reinforced plastics, or a composite material.

5. A sump as claimed in any of claims wherein the top can be provided with a central well and one or more inspection holes giving access to the sump and acting as drainage ports, which are capable of simply being plugged when testing is required.

6. A sump as claimed in any of claims 1 to 5 wherein the lid includes a central well through which the pressure line inputs pass and to which shear valves may be connected.

7. A sump as claimed in claim 6 wherein there are one or more inspection holes capable of being plugged located in the top.

8. A method of testing a petrol sump according to any previous claim which comprises: if necessary, plugging any inspection holes, attaching a vacuum line to the valve in the lid, and pulling a vacuum within the sump.