NZ537532A - Testing device - Google Patents

Abstract

A testing device comprising a substantially hollow tube having a thread at both ends; an inner end being provided with a male thread and a flange supporting a seal so that when the male thread is inserted into a female wingback in use the flange compresses the seal against the wingback with the objective of preventing any fluid leakage at the junction; and at the outer end there is an internal or external thread with an internal sealing chamfer at its tip; and there are grip means provided between the two threaded ends.

Description

53 ' & FORM 5 NEW ZEALAND S.9 Reg. 19(4) Fee: $250.00 PATENTS ACT 1953 Insert number of Provisional Specification(s) (if any) and date(s) of filing; otherwise leave blank Number: Date: Insert Title of Invention TESTING DEVICE COMPLETE SPECIFICATION Insert full name, full street address and nationality of (each) applicant I, DAVID JOHN PICTON, a British citizen, of 356 Point View Drive, R.D. 1, Papatoetoe, Auckland, New Zealand hereby declare the invention for which I pray that a patent may be granted to me and the method by which it is to be performed, to be particularly described in and by the following statement:- Intellectual Property Office of N.Z. 2 i, DEC 200^ rfhfived It is good plumbing practice, when plumbing fittings have been installed in a structure, to test the installation to ensure that it is leakproof. Usually this will involve pressurizing the system to about 220 psi (15.4 kgP/cm2; 1517 kPa ) and checking that the gauge on the test equipment maintains that pressure for at least 30 minutes.

Where wingback fittings have been installed then traditionally these would be female fittings (although a range of male fittings might also be available). A female fitting is versatile because the plumber would simply cut a portion of threaded brass tube of a suitable length to give the required projection from the wingback fitting beyond the structure face surface. Having installed such a length of brass tubing in a female wingback fitting, or where a male wingback fitting is used, it remains to test the installation to ensure it does not leak. The traditional method has been to temporarily put galvanised caps on the protruding thread, introduce water into the system (assuming that one is dealing with a new installation) and then commence to pressurize the system, which will involve loosening the caps to bleed air out of the system and then retightening them to check that there are no leaks over the requisite observation period.

The above technique allows any bled water escaping from the system to be caught well away from the structure's face surface.

However, a less satisfactory practice involves the use of a non-tapered threaded plug (the thread usually being Vz or % inch BSP) provided with a flange against which an annular flat washer is seated and the head of the plug bevond the flanae is shaped to Intellectual Property 0 Office of N.Z. 2 i* DEC 200*1 i—i r r* C I \ / C H form an elongated handle. Such a plug can be inserted into a female wingback fitting and tightened by hand with the annular washer providing the necessary seal between the flange of the plug and the face of the wingback fitting. The difficulty with such a technique, however, is that when air is bled from the system water might also leak from the wingback fitting and might not be able to be caught easily and similarly, when the plug is removed after testing is completed, water can leak into the structure.

The present invention consists in a testing device comprising a substantially hollow tube having a thread at both ends, an inner end being provided with a male thread and a flange supporting a seal so that when the male thread is inserted into a female wingback in use the flange compresses the seal against the wingback with the objective of preventing any fluid leakage at that junction, and at the outer end there is an internal or external thread with an internal sealing chamfer at its tip, and there are grip means provided between the two threaded portions.

One preferred form of the present invention will now be described with reference to the drawing which shows a perspective view of the testing device.

The elongated hollow testing device 1 has two threaded portions, 2 and 3. Inner threaded portion 2 is a male thread and would typically be 1/4 inch or % inch BSP. A flange 4 supports a seal 5 which is preferably an annular seal of a suitable material such as rubber or plastics, but may be an O-ring or a seal of some other cross-sectional shape. The inner threaded portion 2 is adapted to be screwed into a female wingback when the tool is in use. intellectual property office of n.z. - 7 APR 2006 Received An extension portion 6 has a substantially cylindrical wall externally provided with protrusions such as 7 to provide grip means. The grip means also preferably includes a hexagonal cross-sectional area 9, or other cross-section with flats, to enable it to be gripped by a spanner or other suitable tool near the outer end thread. The thread 3 at the outer end is preferably a male thread of V2 inch BSP provided with a chamfer or taper at 10 which is at an angle of 40° to the axis of the thread. The chamfer 10 has a lesser diameter of approximately 14mm and is adapted to co-act with the sealing rib of a cap which forms the subject of N.Z. Patent specification 537530.

That arrangement provides means of sealing off the end of the device very easily but the invention is not limited to use of my cap. The overall length of the device would be about 116.5mm.

When the device is inserted into a female wingback it enables pressure testing of the plumbing installation once a cap or plug is fitted to the outer thread 3. Thus when water is introduced into the system and pressurized to about 220 psi the gauge in the testing device can be viewed for say 30 minutes to ensure that there is no pressure reduction, in which case there are no leaks in the system. However, prior to conducting the pressure test air must be let out of the system and the cap is loosened on the thread 3 to enable that to occur and then re-tightened once water emerges without air. The length of the device standing out from the wingback makes it easy to collect the water into a suitable receptacle such as a bucket. The cap or plug is then properly tightened so that a seal is made and the pressure test is commenced. At the end of testing the cap or plug is unscrewed from the and any water is collected, and then the device is removed from the wingback. intellectual property office of n.z. 4 - 7 APR 2006 received The internal bore of the device would preferably have a taper of 2° towards the centre from each end to enable internal mandrels to be withdrawn as part of the moulding process where the device is made of plastics such as acetal.

Intellectual Property Office N.Z 2 DEC 200^ r e c eiv£d 1

Claims (6)

WHAT I CLAIM IS:

1. A testing device comprising a substantially hollow tube having a thread at both ends, an inner end being provided with a male thread and a flange supporting a seal so that when the male thread is inserted into a female wingback in use the flange compresses the seal against the wingback with the objective of preventing any fluid leakage at that junction, and at the outer end there is an internal or external thread with an internal sealing chamfer at its tip, and there are grip means provided between the two threaded ends.

2. A testing device as claimed in claim 1 whrein said seal is an annular washer.

3. A testing device as claimed in either one of the preceding claims wherein the grip means includes a hexagonal cross-sectioned area provided adjacent the outer end thread.

4. A testing device as claimed in any one of the preceding claims wherein part of the length of the testing device has a substantially cylindrical outer surface and the grip means includes protrusions therefrom.

5. A testing device as claimed in any one of the preceding claims wherein the angle of the chamfer is substantially 40° to the thread axis. 6 intellectual property office of n.z. - 7 APR 2006 received

6. A testing device substantially as herein described with reference to the accompanying drawings. C- O'SbornL DAVID JOHN PICTQN By his authorised agents J.D. HARDIE & CO. intellectual property office of n.z. - ? APR 2006 received 7