FR2466765A1 - Self-contained automatic fluid leak tester - has car valve connected to rechargeable container having safety valve, tap and manometer - Google Patents

Abstract

The equipment contains a compressed air reservoir which allows the required pressure to be introduced into the piping system under test without pumping. A reservoir (1) on a base (8) receives compressed air via a valve (2) and the pressure is measured by a manometer (5). A safety valve (4) prevents excessive pressure being applied to the reservoir owing to the input force or to heating effects. A shut off valve (5) with automatic blocking isolates the pressure regulator. A pressure regulator (9) has a suitable nozzle (10) to permit attachment to the reservoir. A low pressure manometer (13) allows the outlet pressure to be indicated and also indicate leakage. The leak position is detected by commercially obtd. liquid.

Description

The present invention relates to devices of the test pump type for detecting and locating possible leaks from a pipe.

The technique of known devices of this kind of device consists of manual or foot pumps; the pressurization of the network being made by the monipulation of a piston or a pear. This procedure is awkward and only makes it difficult to maintain a low pressure (necessary for leak detection on a low pressure network). In addition, in the event of a leak, the presence of a second operator is necessary: in fact to detect this leak it is necessary to provide flow to the network and therefore to pump at the same time as we are looking for somewhere on the installation the anomaly.

 There are also other types of leak detection devices, which are efficient in design, but require auxiliary energy: electricity, which is not always available at the site.

 The device according to the invention allows the user to check its installation automatically and conveniently in the sense that it is enough to connect the device to the network to put it at the correct pressure without having to pump or adjust manually this pressure. In addition, in the event of a leak detected by the device, there is a sufficient supply of energy @ai (compressed air) to create a flow in the network, allowing the ground operator to search for the leak. using a commercial foaming product.

 The device, object of the invention comprises a tank 1 made of sheet steel intended to receive a volume of compressed air under a pressure of twelve bare by means of an automobile type inflation valve (2) fixed on the part tank top. Is also fixed on the tank - a) a pressure gauge (3) allowing to know the internal pressure and therefore the volume of air available - b) a safety valve (4) calibrated and sealed for a pressure of 12.5 bars thus avoiding any excess of the maximum pressure during inflation or by abnormal heating of the assembly - c) a shut-off valve (5) with self-sealing connector intended to receive and isolate the pressure regulation assembly.

 This tank is also equipped with a handling ring (7) and a base (8) on the bottom.

 This tank is used to store the energy necessary for the leakage checks to be carried out.

This pressure regulator assembly is therefore attached to this reservoir, which is composed of a standard commercial pressure regulator (9) adjusted to an outlet pressure of 50 millibars and sealed at zero flow. On the inlet of this regulator is fixed a plug (10) allowing it to be fixed by simple pressure on the tank: the end piece (10), penetrating into the self-closing connector (6) locks automatically and releases the shutter valve of the fitting allowing the free passage of air from the tank to the installation after opening the valve (5). A filter is placed outside the inlet of the pressure regulator to retain any impurities contained in the compressed air.

 On the outlet of the regulator (9) is placed a nipple (12) pressure gauge holder with throttled passage (to slow down the pressurization). On this nipple is fixed a low pressure manometer (13) with a precision dial of the capsular type graduated from 0 to 100 millibars allowing to know the downstream pressure and to detect a drop in pressure of the controlled network and therefore a possible leak.

At the outlet of the nipple is fixed a flexible hose (14) on which are crimped two mechanical ends with nuts threaded to the pitch of the nipple. These nuts are knurled to allow efficient manual tightening without the need for a tool. The seal is made by means of an elastomer seal fixed captively inside the nuts.

A set of threaded connections (15) on one side of the hose and the other has different threads allowing all possibilities of connection according to the different cases that can be found on different installations to be checked.

The counter operation takes place as follows: the reservoir (1) containing the necessary air charge receives by simple pressure the regulating assembly (9) on the self-sealing connector (6). One side of the flexible hose (14) is then fixed on the outlet nipple (12) of the pressure regulator and the other side, with the intermediary of one of the appropriate couplings (15) connected to the network. In the case of a low pressure natural gas installation it is advisable to connect in place of the counter
This connection being made, the control operation can begin: the stop valve (5) of the tank is opened, thus releasing the air and gradually putting the network under pressure. When the pressure of 50 millibars is reached on the pressure gauge (13), the regulator (9) closes the flow automatically. The user then closes the stop valve (5) of the tank. The tightness control operation begins: if the needle of the low pressure gauge (13) remains stable at 50 millibars for about fifteen minutes if the installation can be considered waterproof. If, on the other hand, it repeats: a leak exists : we can therefore carry out its search by proceeding as follows: open the shut-off valve (5) again, we release the air from the tank and create a flow at pressure of 50 millibars due to the leak, we search for that -this by spraying the different places likely to be leaking with the help of a commercial foaming product. The leak is signaled by the formation of bubbles in the foaming product.

The operator was therefore able to make this tightness check in an easy and practical manner without having to manipulate a pumping system, and he was able to leave far from the device to search for the leak without requiring the presence of a second operator actuating a pumping device intended to create the flow necessary for detecting the leak.

 The filling of the empty tank can be done easily by any service station, inflation is done in the same way as for a tire.

 In the case of contn @@ e of a low-pressure natural gas installation, the pressure test of 50 millibars of compressed air allows compliance with the unified technical document na n 61-1, in force at day of patent filing, recalling that it is compulsory to carry out this test using a neutral gas at the aforementioned pressure.

 The device, object of the invention, can be used in all cases where the leakage control of a pipe or an enclosure must be carried out, provided of course that the volume or the pressure required does not exceed possibilities of the device.

 A variant of the device is provided, with regard to the pressure regulating element, by the possibility of replacing the pressure regulator (9) with an adjustable regulator with regard to the secondary pressure, and the replacement of the pressure gauge. low pressure (13) by a pressure gauge adapted to this regulator. This variant makes it possible to control at a higher pressure certain types of networks requiring a particular control: medium pressure gas piping, fuel, liquid piping etc.

 The foregoing description is given by way of example and does not limit the scope of the invention from which one would not depart by modifying the details of executions cited, by any other similar.

Claims (3)

REVEIDICATIONS i) apparatus for checking the tightness or, if necessary, detecting and locating a leak on a gas or other fluid pipe, or enclosure capable of being tested n compressed air, characterized in that it is composed a refillable tank using a pneumatic automobile type valve, comprising a pressure gauge to control the available pressure, a safety valve, a stop valve with self-sealing connection at its outlet. 2) device according to claim No. 1 characterized in that the complete device comprises for connection to the tank a trigger assembly composed of a standard regulator regulator equipped at its inlet with a plug intended to connect the assembly to the tank instantly , via the self-sealing connection, and at its outlet from a nipple carrying the network pressure control manometer. 3) device according to claim 1 and 2 characterized by the hose, with manual tightening nuts and captive nut seals, intended for the connection of the assembly to the network to be checked.