GB2207723A

GB2207723A - Coupling adaptor for fitting a pressure sensor tube through a hole in a tank

Info

Publication number: GB2207723A
Application number: GB08716684A
Authority: GB
Inventors: Stanley Morgan Maude
Original assignee: Tankmaster Ltd
Current assignee: Tankmaster Ltd
Priority date: 1987-07-15
Filing date: 1987-07-15
Publication date: 1989-02-08
Also published as: GB8716684D0

Abstract

A coupling adaptor for fitting a pressure sensor equipment in the form of a pitot or bubble tube to a hole in a tank includes first and second couplings by means of which sealed connections are made respectively with the tube and the tank, and a chamber in flow communication with, firstly gas in the tank and secondly a conduit disposed outside the tank to which conduit a pressure sensing device may be fitted to sense the gas pressure in the chamber. The gas path from tank to conduit is through the second coupling so that only one hole is required in the tank. A second conduit connected to the chamber may have a pressure regulator fitted thereto. <IMAGE>

Description

COUPLING ADAPTOR FOR FITTING A TUBE THROUGH A HOLE IN A TANK The present invention relates to tanks contents gauges and particularly to couplings used for fitting pitot tubes into a tank.

Many devices for measuring the liquid contents of a tank use pitot tubes which are fed into the tank through a hole in the top of the tank. Holes have specially to be cut into the material of the tank through which the tubes pass, in each case being attached to the tank by connection with screw threaded couplings. In the case of pressurised tanks a further hole has to be made in the tank through which the pressure of the gas above the liquid can be sensed.

Every time a coupling is used there is a possibility that inadequate sealing of the components will lead to leakage.

It will therefore be appreciated that the fitting of pressure sensing equipment would be improved by reducing the number of holes required to be made in the tank and preferably also the number of couplings required to be made.

According to the present invention there is provided a coupling adaptor for fitting pressure sensing equipment to a hole in a tank, the adaptor comprising means allowing passage therethrough of a pitot tube, and including a first coupling by means of whiCh a sealed connection can be made with the pitot tube, and a second coupling by means of which a sealed connection can be made with the tank, a chamber located above the second coupling and, in use, in flow communication with the gas in the tank through the second coupling, and a conduit in flow communication with the chamber and adapted to receive a pressure sensor by means of which pressure in the chamber can be sensed.

Preferably the conduit comprises an arm connected by a shoulder to a collar in which the chamber is disposed.

A.subsidiary problem is that, where equipment is fitted to withstand a maximum pressure it is important that this pressure is not exceeded. This problem may be mitigates1 providing a second conduit from the chamber to which is fitted a pressure regulator.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view,partially sectioned, of a coupling adaptor according to the present invention, Figure 2 is a plan view of the adaptor of Figure 1, Figure 3 is a side view of the adaptor of Figure 1 and Figure 4 is a longitudinal section of the adaptor of Figure3.

The drawings illustrate a coupling adaptor for fitting a pitot tube to a pressurised tank. The adaptor comprises a coupling 10 externally screw threaded at 11 to receive an olive (not shown) to form a compression fitting the tightening of which clamps a:tube:l3 in position in the coupling pasting coaxially through the centre of the coupling.The outer diameter of the tube is equal to the inner diameter. of the coupling sleeve 10 so that by using traditional sealing materials a good seal can be made. Thus no gas from the tank should escape through this coupling. The adaptor also includes a second coupling sleeve 14 which is externally screw threaded and by means of usual sealing materials can make an air tight seal with cooperating threads in the tank cover 15.The first and second coupling sleeves 10,14 are coaxially mounted with a collar 16 disposed therebetween, which. collar, is use, sits on the upper surface of the tank cover 15. The lower second coupling 14 has a larger diameter than the upper first coupling 10 and this allows an annular space 17 between the sleeve 14. and the tube 13. The collar 16 opens upwardly into the sleeve 10 at the same diameter and downwardly into the sleeve 14 at the same diameter as the sleeve 14. In beteen the collar.comprises an annular chamber 18 in flow communication with the space 17.

The chamber 17 is thus a supply of gas at a pressure substantially equaL to that above the liquid in the tank. A pressure reading of this gas will therefore give a reliable reading of the gbs in the tank.

Two conduit arms 19,20 connect to the collar 16 via respective shoulders 21,22. The conduits within the arms and shoulders are in flow communication with the chamber 17.

By using shoulders 21,22, to connect the arms 19,.20 to the chamber 17 exposure is made to a half of the chamber thus ensuring as reliable a reading of the gas pressure in the chamber as possible. The first arm 19 im adapted to receive at the top 21 thereof a pressure sensing head (not shown) suitable for taking a pressure reading of gas in the chamber 17. The second arm 20 is adapted to receive a pressure regulator (not shown.) by means of which the pressure in the tank can be limited to an upper predgermined pressure. Any potential build up in excess of this predetermined maximum can be eased by allowing gas release to atmosphere until the required pressure is restored. Optionally equipment may be provided for increasing the gas pressure should it fall below the level required.

By using this adaptor with a double pitot tube (two concert rically mounted tubes ) it is possible through a single hole in the tank cover to take all the pressure readings necessary for determination of specific gravity and liquid level. This is not only a major saving in effort because of the need for only a single hole in the tank, but it is also a great advantage to have reduced the number of couplings that have to be made and thus the number of potential gas leaks.

Claims

1. A coupling adaptor for fitting pressure sensing equipment including a pressure sensor tube to a hole in a tank; the adaptor comprising means allowing passage of the tube therethrough and including a first coupling for making a sealed connection with the tube outside the tank and a second coupling for making a sealed connection with the tank; a chamber in flow communication, in use, with gas in the tank and a conduit disposed, in use outside the tank and in flow communication with the chamber and adapted to receive a pressure sensor by means of which pressure in the chamber can be determined.

2. A coupling adaptor according to claim 1 including a second conduit disposed, in use, outside the tank and in flow communication with the chamber, and adapted to receive a pressure regulator.

3. A coupling adaptor according to claim 1 or 2 wherein the chamber is formed in a collar disposed between the first and second couplings for location outside the tank, the gas flow path between the chamber alld the tank being through the second coupling.

4. A coupling adaptor according to claim 3 wherein the first and second couplings are coaxial with one another with the collar therebetween, the second coupling having internal dimensions which allow gas to flow between the coupling internal wall and the tube.

5. A coupling adaptor according to any of the preceding claims wherein the first conduit opens into at least half the volume of the chamber.

6. A coupling adaptor substantially as herein described, with reference to the accompnaying drawings.