GB2190464A

GB2190464A - Pipe fitting

Info

Publication number: GB2190464A
Application number: GB08611110A
Authority: GB
Inventors: Maurice Binder
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-05-07
Filing date: 1986-05-07
Publication date: 1987-11-18
Also published as: GB8611110D0

Abstract

A pipe fitting comprises a body (2), a plunger (4) displaceable in said body between a sealing position in which, in use, steam is precluded from entering said body (2), and an open position in which steam can enter said body, and a test point (16) which communicates with the inside of said body. The test point (16) consists of a valve member 18 which is biassed to a closed position and adapted to be opened on insertion of a probe. The fitting is used to tap steam from a pipe,a pressure gauge being connected at the test point (16). <IMAGE>

Description

SPECIFICATION Pipe fitting This invention relates to pipe fittings and, more particularly but not exclusively, to pipe fittings for steam pipes.

According to the present invention there is provided a pipe fitting which comprises a body, a plunger displaceable in said body between a sealing position in which, in use, steam is precluded from entering said body, and an open position in which steam can enter said body, and a test point which communicates with the inside of said body.

Preferably, rotation of said plunger moves it between its sealing position and its open position.

Advantageously, said plunger is provided with an enlarged annular section and a seal circumjacent said enlarged annular section in sealing contact with said body to inhibit steam in the inside of said body existing between said plunger and said body.

Preferably, one end of said plunger is provided with a tongue which is advantageouslywholly contained within the confines of said body when said plunger is in its sealing position.

Advantageously, said plunger is screw threadedly mounted in said body via a bush.

Preferably, said test point comprises a sealing member which is biased to a closed position, but which can be upset bythe insertion of a probetoallow, in use, steamtoflowtherethrough.

For a better understanding ofthe invention reference will now be made, by way of example, to the accompanying drawing which is a simplified crosssection through a pipe fitting in accordance with the invention.

Referring to the drawing, there isshown a pipe fitting which is generally identified by reference numeral 1.

Thepipefitting 1 comprises a body2which has a threaded end 3 adapted to be screwed into athreaded bore in the wall of a steam pipe (not shown).

The body 2 houses a plunger 4 which can be displaced axiallyofthe body 2. One end ofthe plunger 4 is provided with a concave end face 5, whilstthe other end isthreadedly mounted in a bush6 6 mounted in the body 2.

When the plunger 4 is rotated in one sense the concave end face 5 biases a stainless steel ball 7 against a seal 8 which prevents steam entering the pipefitting 1 via inlet passageway9.

When the plunger 4 is rotated in the opposite sense the concave end faceS moves away from the inlet passageway 9 so that steam entering the inlet passageway 9from the steam pipe (not shown) displaces the stainless steel ball 7from the seal 8 and enters the inside 10 ofthe body 2.

The plunger4 is provided with an enlarged annular section 11 which is provided with a seal 12 which prevents steam exiting via the screw threaded joint between the plunger4andthe bush 6.

The plunger4 is provided with a tongue 13 which is totally contained within the bush 6when the stainless steel ball 7 is biased into engagement with the seal 8.

Thetongue 13 can be gripped byatool 14 having an end 15 of"U" shape cross-section.

Atest point 16 is mounted on the body 2 as shown.

The test point 16 comprises a body 17 containing a stainless steel ball 18 which is biased against a TEFLON (RTM) seal 19 by a spring 20. The test point 16 is also provided with a detachable screw threaded cap 21.

During normal use the parts of the pipe fitting 1 are arranged in the position shown in the drawing but with the end cap 21 screwed onto the end ofthe test point 16. In orderto measure, for examplethe pressure of steam in the steam pipe (not shown), the end cap 21 is first removed. A pressure guage is then connected to the test point 16 via an adaptorwhich comprises a threaded cap which contains a hollow tube which, as the threaded cap is screwed onto the test point 16 engages and displacesthestainlesssteel ball 18 and communicates with the inside 10 of the body 2 via passageway 22.

Once the adaptor is fully connected the end 15 of the tool 14 is inserted into the bush 6 and engages the tongue 13. The tool is then rotated to displace the plunger4to the right as viewed in the drawing.

Steam upsets'the stainless steel ball 7 and passes through the inside 10 ofthe body 2, through the pasageway 22 into the test point 16 and thence to the pressure guage.

When the pressure measurement is completed the tool 14 is used to rotate the plunger4so that it urges the stainless steel ball 7 into sealing contact with the seal 8thereby preventing further steam entering the inside 10 ofthe body 2. The adaptor is then disconnected and the cap 21- replaced.

The adaptor is dimensioned sothatthe stainless steel ball 18will seat on the TEFLON seal 19 several turns before the threaded cap becomes detached from the test point 16. Accordingly, the risk of scalding is minimal even if the adaptor is accidentally removed (or connected) before the stainless steel ball 7 is moved into sealing engagement with the seal 8.

Various modifications to the embodiment described with reference to the drawing are envisaged, for example the plunger4 could conceivably be arranged to make direct sealing contact with the body to prevent steam entering inside of the body.

1. A pipe fitting which comprises a body, a plunger displaceable in said body between a sealing position in which, in use, steam is precluded from entering said body, and an open position in which steam can enter said body, and a test point which communicates with the inside of said body.

2. A pipe fitting as claimed in Claim 1,wherein rotation of said plunger moves it between its sealing position and its open position.

3. A pipe fitting as claimed in Claim 1 or 2, wherein said plunger is provided with an enlarged annular section and a sealcircumjacent said enlarged annular section in sealing contactwith said body to inhibit steam in the inside of said body exiting between said plunger and said body.

4. A pipe fitting as claimed in any preceding Claim, wherein one end of said plunger is provided with a tongue.

5. A pipe fitting as claimed in Claim 4, wherein said

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Pipe fitting This invention relates to pipe fittings and, more particularly but not exclusively, to pipe fittings for steam pipes. According to the present invention there is provided a pipe fitting which comprises a body, a plunger displaceable in said body between a sealing position in which, in use, steam is precluded from entering said body, and an open position in which steam can enter said body, and a test point which communicates with the inside of said body. Preferably, rotation of said plunger moves it between its sealing position and its open position. Advantageously, said plunger is provided with an enlarged annular section and a seal circumjacent said enlarged annular section in sealing contact with said body to inhibit steam in the inside of said body existing between said plunger and said body. Preferably, one end of said plunger is provided with a tongue which is advantageouslywholly contained within the confines of said body when said plunger is in its sealing position. Advantageously, said plunger is screw threadedly mounted in said body via a bush. Preferably, said test point comprises a sealing member which is biased to a closed position, but which can be upset bythe insertion of a probetoallow, in use, steamtoflowtherethrough. For a better understanding ofthe invention reference will now be made, by way of example, to the accompanying drawing which is a simplified crosssection through a pipe fitting in accordance with the invention. Referring to the drawing, there isshown a pipe fitting which is generally identified by reference numeral 1. Thepipefitting 1 comprises a body2which has a threaded end 3 adapted to be screwed into athreaded bore in the wall of a steam pipe (not shown). The body 2 houses a plunger 4 which can be displaced axiallyofthe body 2. One end ofthe plunger 4 is provided with a concave end face 5, whilstthe other end isthreadedly mounted in a bush6 6 mounted in the body 2. When the plunger 4 is rotated in one sense the concave end face 5 biases a stainless steel ball 7 against a seal 8 which prevents steam entering the pipefitting 1 via inlet passageway9. When the plunger 4 is rotated in the opposite sense the concave end faceS moves away from the inlet passageway 9 so that steam entering the inlet passageway 9from the steam pipe (not shown) displaces the stainless steel ball 7from the seal 8 and enters the inside 10 ofthe body 2. The plunger4 is provided with an enlarged annular section 11 which is provided with a seal 12 which prevents steam exiting via the screw threaded joint between the plunger4andthe bush 6. The plunger4 is provided with a tongue 13 which is totally contained within the bush 6when the stainless steel ball 7 is biased into engagement with the seal 8. Thetongue 13 can be gripped byatool 14 having an end 15 of"U" shape cross-section. Atest point 16 is mounted on the body 2 as shown. The test point 16 comprises a body 17 containing a stainless steel ball 18 which is biased against a TEFLON (RTM) seal 19 by a spring 20. The test point 16 is also provided with a detachable screw threaded cap 21. During normal use the parts of the pipe fitting 1 are arranged in the position shown in the drawing but with the end cap 21 screwed onto the end ofthe test point 16. In orderto measure, for examplethe pressure of steam in the steam pipe (not shown), the end cap 21 is first removed. A pressure guage is then connected to the test point 16 via an adaptorwhich comprises a threaded cap which contains a hollow tube which, as the threaded cap is screwed onto the test point 16 engages and displacesthestainlesssteel ball 18 and communicates with the inside 10 of the body 2 via passageway 22. Once the adaptor is fully connected the end 15 of the tool 14 is inserted into the bush 6 and engages the tongue 13. The tool is then rotated to displace the plunger4to the right as viewed in the drawing. Steam upsets'the stainless steel ball 7 and passes through the inside 10 ofthe body 2, through the pasageway 22 into the test point 16 and thence to the pressure guage. When the pressure measurement is completed the tool 14 is used to rotate the plunger4so that it urges the stainless steel ball 7 into sealing contact with the seal 8thereby preventing further steam entering the inside 10 ofthe body 2. The adaptor is then disconnected and the cap 21- replaced. The adaptor is dimensioned sothatthe stainless steel ball 18will seat on the TEFLON seal 19 several turns before the threaded cap becomes detached from the test point 16. Accordingly, the risk of scalding is minimal even if the adaptor is accidentally removed (or connected) before the stainless steel ball 7 is moved into sealing engagement with the seal 8. Various modifications to the embodiment described with reference to the drawing are envisaged, for example the plunger4 could conceivably be arranged to make direct sealing contact with the body to prevent steam entering inside of the body. CLAIMS

5. A pipe fitting as claimed in Claim 4, wherein said tongue is wholly contained within the confines of said body when said plunger is in its sealing position.

6. A pipe fitting as claimed in any preceding claim, wherein said plunger is screwthreadedly mounted in said body via a bush.

7. A pipe fitting as claimed in any preceding claim, wherein said test point comprises a sealing member which is biased to a closed position but which can be upset by the insertion of a probe to allow, in use, steam to flow therethrough.

8. A pipefittingsubstantially as hereinbefore described with reference to and as shown in the accompanying drawing.