CA1316899C

CA1316899C - Isolator valve

Info

Publication number: CA1316899C
Application number: CA000556176A
Authority: CA
Inventors: James R. Ellett
Original assignee: Barber Industries Ltd
Current assignee: Barber Industries Inc
Priority date: 1988-01-08
Filing date: 1988-01-08
Publication date: 1993-04-27
Anticipated expiration: 2010-04-27

Abstract

ABSTRACT OF THE DISCLOSURE
An isolator valve for the calibration of a pilot valve on a flow system. The valve isolates the pilot valve which may then be calibrated without disconnecting the pilot valve from the flowline.

Description

`` 1 31 6899 INTRODUCTION

This invention relates to an isolator valve and, more particularly, to an isolator valve which is integral and particularly adapted for use with a flowline.

BACKGROUND OF THE INVENTION

Pilot valves are utilised to monitor the pressure in a flowline such as an oil flowline. When the pressure sensed exceeds a desired operating range, the pilot valve is activated by the excess pressure. This activation typically signals a main valve in the flowline to either close or open which will stop or commence flow. In this way, the pilot valve is used to protect the operation of the flowline and to ensure its operation is within `~
predetermined acceptable limits.

The actuation pressure of the pilot valve is normally set by an adjustment located on the pilot valve itself. Although the adjustment may indicate approximate actuation pressures, the true actuation pressure is only determined by a calibration test. Over time, the actuation pressure may change and, in addition, the calibration pressures may be required to be changed because of the different operating pressures which may be desired.

In the past, calibration testing was performed b~
installing a series of components on the flowline. A first flange was installed in a female connector on the flowline and a second flange was connected to the first flange with appropriate studs and nuts connected to the studs on opposite sides of the flanges. A ball valve was then connected to the second flange for opening and closing the ~ 35 line between the flowline and the pilot valve. A further -; pair of flanges were then connected to the downstream end of the ball valve and a steel cross member was mounted to ~.
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`` 1 3 1 689q the downstream end o~ the flanges. The pilot valve was mounted to the downstream end of the cross member together with a pressure gauge and a bleed valve.

By closing the ball valve, fluid in the flowline is isolated from the cross member and by opening the bleeder valve, the residual fluid pressure in the cross member may be bled off. A hand pump is then attached to the bleeder valve and the pressure in the cross member may be increased. The gauge is observed while the pressure is increased and, by adjusting the pressure setting or settings for the pilot valve, the desirable operating limits may be set on the pilot valve.
The apparatus previously used included a number of components which resulted in an isolator apparatus having an unnecessarily long dimension lengthwise.
In addition to the increased costs resulting from extra material and components, the distance of the pilot valve from the flowline made the apparatus susceptible to freezing off or waxing whan used under cold weather conditions.

SUMMARY OF THE INVENTION

According to the invention, there is disclosed an isolator comprising lengthwise separable inlet and outlet ports mounted in respective first and second members, said first member being adapted to be connected to a pressure source such that said first member extends transversely outwardly from said pressure source, a f irst chamber operably connected to said inlet port, a second chamber operably connected to said outlet port and said first chamber, said first and second members being 'f,~ ~
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threadedly connected to a body member which surrounds the threaded end of each of said first and second members, gauge and bleeder valve connection means operably associated with said second chamber in said second member and first valve means mounted in said body member and being operable to isolate said first from said second chamber and to isolate said second chamber from said pressure source, said second chamber ~eing mounted downstream from said first valve means.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

A specific embodiment of the invention will now be described, by way of example only, with the use of drawings in which:

Figure 1 is a diagrammatic side view of the isolator in its operating environment between a pilot valve and a flowline according to the invention: and Figure 2 is a sectional and enlarged view of the isolator according to the invention.

DESCRIPTION OF SPECIFIC EMBODIMENT

Referring now to the drawings, an isolator is illustrated generally at 10 in Figure 1 in its ~perating environment between the pilot valve 11 and the flowline 12. Flowline 12 extends between a production well (not shown), for example, and a storage tank ~not shown~.

Flowline 12 is also connected to an actuator generally shown at 13. The purpose of the actuator ,;.. ~

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13 and its operation will be described in more detail hereafter.

Reference is now made to Figure 2. The isolator 10 comprises a first integral male member 14 with external thread~ 20 which form the periphery of an inlet port 21. The external threads 20 are operable to be connected with a female "T" coupling 22 operably mounted to the flowline 12.
A first chamber 23 within the male member 14 is operably connected to the inlet port 21 and extends into a body member 25 with an external threaded connection 80 on male member 14 which couples with a complementary threaded female connection 81 on body member 25. It is ].engthwise separable from but connected with a second chamber 24. Second chamber 24 extends from body member 25 into an integral female member 30 through an external threaded connection 82 which couples with an integral threaded connection on body member 25. Internal threads 31 formed within female member 30 are adapted to be connected to a male member 32 extending from the pilot valve 11 and form an outlet port 33.
A ball valve generally shown at 34 is operably mounted within the first chamber 23 and the integral body member 25. Ball valve 34 comprises a rotatable ball 40 movable 90 degrees about axis 41. The ball 40 has groove 42 machined therein which is adapted to fit the tongue 46 of valve stem 43. Valve stem 43 extends outwardly from body member 25 normal to the : axis 44 of the isolator 10. A handle 50 is connected to the top oE valve stem 43 and is rigidly secured with a nut 51. The ball 40 is located and held between ~eats 47, 48, each of the seats being '.~

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retained in respect of counter bores o~ male member 14 and female member 30. Two O-ring seals 56, 57 are mounted between the seats 47, 48 and the first and second members 30, 14, respectively.

A locki~g member 52 is mounted around the valve stem 43. It has first and secGnd arms 53, S4, each of the arms 53, 54 having holes 6~, 61, respectively, which are adapted to alluw the insertivn ~f a lock (not shown) in either the holes 60, 61 and, simultaneously, hole 62 of handle ~0 depending upon the position o~ the handle either as illustrated in Figure 2 or the closed position of the handle 50 where it is moved 90 degrees downwardly as illustrated in phantom in Figure 1.

Two access or connection ports 63, 64 are located in the female member 30. They extend outwardly and are normal to the longitudinal axis 44 of the isolator 10. A pressure gauge 70 is mounted within access port 63 and a bleeder valve 71 is mounted within access port 64. Bleeder valve 71 has a handle 72 which will allow the valve 71 to be open or closed. Bleeder valve 71 further has an inlet port 73 which is operable to allow a hand pump (not shown) to be connected.

OPERATION

In operation, it will be assumed that the flowline 12 will normally have a fluid such as oil flowing therethrough under usual pressure conditions.
The pilot valve 11 will have an upper and lower pressure range programmed such that in the event the pressure within the ~lowline 12 goes outside these pressure limits as would be the case, for example, , ' when the flowline 12 was ruptured, the pilot valve 11 will activate the actuator 13 which immediately closes the flowline 12 and prevents further flow.
The operation of the pilot valve 11 and the actuator 13 is not material to the present invention and will not be further described.

Under the normal conditions described, the handle ~0 of the actuator 10 will be in the position illustrated in the figures. That is, it will be parallel with the axis 44 of the isolator 10 and the ball 40 will be in the open position allowing oil from the flowline 12 to flow between the inlet and outlet ports 21, 23, respectively.
It will next be assumed that calibration of the pilot valve 11 is desired either to assure the correct operating range for the flowline 12 is being monitored or to change the operating range for the flowline 12.

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The handle 50 will be rotated clockwise when viewed in Figure 1 to the position 74 illustrated in phantom. This will rotate ball 40 ninety degrees and will close the isolator such that flow between the inlet and outlet ports, 21,33, respectively, will cease. If desired, bleeder valve 71 can be opened by turning handle 72 and the oil pressure remaining in second chamber 24 can ~e bled o~f. A hand pump (not shown3 is then connected to the inlet port 73 of the bleeder valYe 71 and is operated to raise the pressure within second chamber 24 while obser~ing the pressure indicated on the pressure gauge 70.
When the desired pressure is reached, the handle 72 is turned to close the bleeder valve 71 and the pilot valve 11 is set to react to the particular pressure indicated.
If a second lower pressure limit on the pilot valve 11 is desired, then the bleeder valve 71 is again opened slowly such that a lower pressure is indicated on the gauge 70 whereas the bleeder valve 71 is again closed and the pilot valve 11 is set with the second lower limit.

Following the calibration of the pilot valve 11, the handle 50 is rotated back to its original position and the ; operation of the isolator 10, pilot valve 11 and actuator 13 will proceed as is normal.

To prevent tampering, the locking member 52 will allow the insertion of a padlock (not shown) between the holes 60,61 in locking member 52 and a complementary hole 62 on handle 50, depending on whether the open or closed position is desired.

Many modifications to the apparatus described will readily occur to those skilled in the art. For example, while a ball valve 34 is utilized, clearly any type of valve conveniently may be used to open and close the first chamber 23 and the access between the inlet and outlet ports 21,33, respectively. The isolator valve, while being described as used with oil, could also be used in association with any fluid and particularly gas or water or any combination oE these ele~nents.

Many further modifications to the invention may ~e readily contemplated by those skilled in the art and the specific embodiments disclosed should be considered illustrative only and not as limiting the scope of the invention as construed in accordance with the accompanying claims.

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Claims

1. An isolator comprising lengthwise separable inlet and outlet ports mounted in respective first and second members, said first member being adapted to be connected to a pressure source such that said first member extends transversely outwardly from said pressure source, a first chamber operably connected to said inlet port, a second chamber operably connected to said outlet port and said first chamber, said first and second members being threadedly connected to a body member which surrounds the threaded end of each of said first and second members, gauge and bleeder valve connection means operably associated with said second chamber in said second member and first valve means mounted in said body member and being operable to isolate said first from said second chamber and to isolate said second chamber from said pressure source, said second chamber being mounted downstream from said first valve means.

2. An isolator as in claim 10 and further comprising flowline attachment means on said first member.

3. An isolator as in claim 2 and further comprising pilot valve attachment means on said second member.

4. An isolator as in claim 1 wherein said gauge and bleeder valve connection means are access ports extending substantially normal to the longitudinal axis of said isolator.

5. An isolator as in claim 1 wherein said first valve means in said body member is a ball valve, which ball valve is operably also mounted within said first and second body members.

6. An isolator as in claim 4 wherein a gauge and a bleeder valve are each connected to said access ports.

7. An isolator as in claim 1 and further comprising a pump connection on said bleeder valve.

8. An isolator as in claim 1 and further comprising a handle connected to said first valve means, said handle extending from said body member.

9. An isolator as in claim 8 and further comprising locking means for said handle.

10. An isolator as in claim 1 wherein said pressure source is a flowline and said first member extends traversely outwardly from the axis of said flowline.