Differential pressure sensor and isolation valve manifold assembly

• US 6,349,735 B2
• Filed: 02/07/2001
• Issued: 02/26/2002
• Est. Priority Date: 02/07/2000
• Status: Expired due to Term

• Current Assignee: Mamac Systems Incorporated
• Original Assignee: Mamac Systems Incorporated
• Inventors: Gul, S. Asim
• Primary Examiner(s): CHAMBERS, A MICHAEL
• Application Number:
  US09/778,674
• Publication Number:
  US 20010039964A1
• Time in Patent Office: 384 Days
• Field of Search: 137/557, 137/360, 137/552, 137/14, 137/554, 137/15.09, 137/357, 137/315.01, 137/315.04
• US Class Current: 137/15.09
• CPC Class Codes: G01L 19/0015 using switching means
• CPC Class Codes: Y10T 137/0447 Including joint or coupling
• CPC Class Codes: Y10T 137/698 Wall
• CPC Class Codes: Y10T 137/8175 Plural
• CPC Class Codes: Y10T 137/8326 Fluid pressure responsive indicator, recorder or alarm

Abstract

A pressure monitoring assembly includes an isolation valve assembly and a differential pressure sensor assembly. The rigid manifold has two pressure inlet ports which each communicate with respective pressure outlet ports through isolation valves. An equalization passage and valve connect the two pressure lines. The pressure sensor assembly is sized to mate directly with the monolithic manifold by having sensor inlet ports that line up with the pressure outlet ports. Pressure tight attachments releasably secure the pressure sensor assembly to the manifold, but a rigid to support the weight of the pressure sensor assembly. No bleeding valves are necessary. Orientation and the positioning and construction of the manifold effectively reduce the amount of heat transfer between the pressure lines and the pressure sensor(s).

Claims

1. A method of assembling a pressure monitoring assembly comprising:

providing an isolation valve assembly comprising;

a rigid manifold having a first pressure inlet port, a first pressure outlet port, a second pressure inlet port and a second pressure outlet port, the first pressure outlet port and the second pressure outlet port being aligned in a parallel relationship with an outlet port spacing between the first pressure outlet port and the second pressure outlet port;

a first isolation valve adjustable between an opened position in which the first pressure inlet port is in fluid communication with the first pressure outlet port and a closed position in which flow in the rigid manifold from the first pressure inlet port to the first pressure outlet port is stopped; and

a second isolation valve adjustable between an opened position in which the second pressure inlet port is in fluid communication with the second pressure outlet port and a closed position in which flow in the rigid manifold from the second pressure inlet port to the second pressure outlet port is stopped;

positioning the isolation valve assembly on an underlying planar surface with the first and second pressure outlet ports defining axes extending parallel to the underlying planar surface;

providing a pressure sensor assembly comprising;

a first pressure sensor port; and

a second pressure sensor port rigidly secured relative to the first pressure sensor port, the first pressure sensor port and the second pressure sensor port being aligned in a parallel relationship with a sensor port spacing between the first pressure sensor port and the second pressure sensor port, wherein the sensor port spacing equals the outlet port spacing;

positioning the pressure sensor assembly on the underlying planar surface such that the first and second pressure sensor ports define axes which are aligned colinear with respective axes of the first and second pressure outlet ports;

sliding the pressure sensor assembly and the isolation valve assembly toward one another on the underlying planar surface;

releasably securing the first pressure outlet port to the first pressure sensor port in a pressure tight manner; and

releasably securing the second pressure outlet port to the second pressure sensor port in a pressure tight manner.

2. A pressure monitoring assembly comprising:

an isolation valve assembly comprising;

a rigid manifold having a first pressure inlet port, a first pressure outlet port, a second pressure inlet port and a second pressure outlet port, the first pressure outlet port and the second pressure outlet port being aligned in a parallel relationship with an outlet port spacing between the first pressure outlet port and the second pressure outlet port;

a first isolation valve adjustable between an opened position in which the first pressure inlet port is in fluid communication with the first pressure outlet port and a closed position in which flow in the rigid manifold from the first pressure inlet port to the first pressure outlet port is stopped; and

a second isolation valve adjustable between an opened position in which the second pressure inlet port is in fluid communication with the second pressure outlet port and a closed position in which flow in the rigid manifold from the second pressure inlet port to the second pressure outlet port is stopped;

a pressure sensor assembly comprising;

a first pressure sensor port; and

a second pressure sensor port rigidly secured relative to the first pressure sensor port, the first pressure sensor port and the second pressure sensor port being aligned in a parallel relationship with a sensor port spacing between the first pressure sensor port and the second pressure sensor port, wherein the sensor port spacing equals the outlet port spacing;

a first pressure tight attachment mechanism for releasably securing the first pressure outlet port to the first pressure sensor port in rigid alignment and in a pressure tight manner; and

a second pressure tight attachment mechanism for releasably securing the second pressure outlet port to the second pressure sensor port in rigid alignment and in a pressure tight manner.

3. The pressure monitoring assembly of claim 2, further comprising:

an electrical box having walls defining an enclosure for making electrical connections;

at least one pressure sensor providing the first pressure sensor port and the second pressure sensor port and further comprising electrical leads to output an electrical signal representative of fluid pressure differential between the first pressure sensor port and the second pressure sensor port;

wherein the electrical box rigidly supports the at least one pressure sensor such that the first pressure sensor port and the second pressure sensor port extend outside the electrical box and the electrical leads extend within the electrical box.

4. The pressure monitoring assembly of claim 2, further comprising:

an electrical box having walls defining an enclosure for making electrical connections;

a first pressure sensor providing the first pressure sensor port and further comprising;

a first diaphragm in fluid communication with the first pressure sensor port;

first electrical leads to output an electrical signal representative of fluid pressure on the first diaphragm; and

a second pressure sensor providing the second pressure sensor port and further comprising;

a second diaphragm in fluid communication with the second pressure sensor port;

second electrical leads to output an electrical signal representative of fluid pressure on the second diaphragm;

wherein the electrical box rigidly supports first pressure sensor and the second pressure sensor such that the first pressure sensor port and the second pressure sensor port extend outside the electrical box and the first electrical leads and the second electrical leads extend within the electrical box.

5. The pressure monitoring assembly of claim 4, further comprising:

an electrical circuit within the electrical box for electronically comparing fluid pressure on the first diaphragm and fluid pressure on the second diaphragm to output an electrical signal representative of differential fluid pressure.

6. The pressure monitoring assembly of claim 2, wherein the first pressure tight attachment mechanism and the second pressure tight attachment mechanism can support the weight of the pressure sensor assembly without substantial bending.

7. The pressure monitoring assembly of claim 6, mounted such that the isolation valve assembly is mounted over the pressure sensor assembly to reduce heat transfer from the isolation valve assembly to the pressure sensor assembly.

8. The pressure monitoring assembly of claim 2, wherein the rigid manifold is unitarily formed from a single block of metal having an exterior surface area of at least about 10 square inches.

9. The pressure monitoring assembly of claim 2, wherein the isolation valve assembly further comprises:

an equalization connection formed in the rigid manifold permitting fluid communication between the first pressure outlet port and the second pressure outlet port through the rigid manifold;

an equalization valve adjustable between an opened position permitting fluid communication through the equalization connection between the first pressure outlet port and the second pressure outlet port and a closed position sealing the first pressure outlet port from the second pressure outlet port.

10. The pressure monitoring assembly of claim 9, wherein the equalization valve is a pin-in-seat valve with a polytetrafluoroethylene coated seat.

11. The pressure monitoring assembly of claim 2, wherein the parallel first and second pressure outlet ports define an axial direction, and wherein isolation valve assembly further comprises an attachment bracket without oblong attachment holes permitting the isolation valve to be secured to an underlying surface at an axially adjustable position.

12. The pressure monitoring assembly of claim 2, wherein:

the isolation valve assembly further comprises an attachment bracket for mounting the rigid manifold off an underlying planar surface, with the first pressure outlet port having a first axis parallel to the underlying surface with a first clearance, with the second pressure outlet port having a second axis parallel to the underlying planar surface with a second clearance; and

the pressure sensor assembly further comprises an attachment bracket for mounting the pressure sensor assembly to the underlying planar surface, with the first pressure sensor port being coaxial with the first axis and the second pressure sensor port being coaxial with the second axis.

13. The pressure monitoring assembly of claim 2, wherein:

the isolation valve assembly further comprises an attachment bracket for mounting the rigid manifold off an underlying planar surface, the attachment bracket raising the rigid manifold off the underlying planar surface to allow air flow between the rigid manifold and the underlying planar surface for enhanced heat transfer from the rigid manifold.

14. The pressure monitoring assembly of claim 2, wherein the first pressure tight attachment mechanism and the second pressure tight attachment mechanism each comprise:

a male tube stub extension;

a female tube stub extension opposing the male extension and sized to mate around the male tube stub extension to withstand the weight of the pressure sensor assembly without substantial bending, the female tube stub extension having an external thread; and

a compression nut rotatable on the external thread of the female tube stub extension and about an axis of the male tube stub extension and the female tube stub extension to compress the male tube stub extension and the female tube stub extension together in a pressure tight connection.

15. The pressure monitoring assembly of claim 2, wherein, with the pressure sensor assembly attached to the isolation valve assembly, the first pressure sensor port is no more than six inches from the first isolation valve and the second pressure sensor port is no more than six inches from the second isolation valve.

16. The pressure monitoring assembly of claim 2,

wherein the isolation valve assembly is adapted for mounting on an underlying planar surface with the first and second pressure outlet ports defining axes extending parallel to the underlying planar surface when mounted;

and

wherein the pressure sensor assembly is adapted for mounting on the underlying planar surface such that the first and second pressure sensor ports define axes which are colinear with the respective axes of the first and second pressure outlet ports,

such that the pressure sensor assembly can be aligned with and positioned relative to the isolation valve assembly by sliding the pressure sensor assembly and the isolation valve assembly toward one another on the underlying planar surface.

17. A pressure monitoring assembly comprising:

an isolation valve assembly comprising;

a rigid manifold having a first pressure inlet port, a first pressure outlet port, a second pressure inlet port and a second pressure outlet port, the first pressure outlet port and the second pressure outlet port being aligned in a parallel relationship with an outlet port spacing between the first pressure outlet port and the second pressure outlet port;

a first isolation valve adjustable between an opened position in which the first pressure inlet port is in fluid communication with the first pressure outlet port and a closed position in which flow in the rigid manifold from the first pressure inlet port to the first pressure outlet port is stopped; and

a second isolation valve adjustable between an opened position in which the second pressure inlet port is in fluid communication with the second pressure outlet port and a closed position in which flow in the rigid manifold from the second pressure inlet port to the second pressure outlet port is stopped;

a pressure sensor assembly comprising;

a first pressure sensor port; and

a second pressure sensor port rigidly secured relative to the first pressure sensor port, the first pressure sensor port and the second pressure sensor port being aligned in a parallel relationship with a sensor port spacing between the first pressure sensor port and the second pressure sensor port, wherein the sensor port spacing equals the outlet port spacing;

a first pressure tight attachment mechanism for releasably securing the first pressure outlet port to the first pressure sensor port in rigid alignment and in a pressure tight manner;

a second pressure tight attachment mechanism for releasably securing the second pressure outlet port to the second pressure sensor port in rigid alignment and in a pressure tight manner;

wherein the first pressure tight attachment mechanism and the second pressure tight attachment mechanism can support the weight of the pressure sensor assembly with the pressure sensor assembly hanging under the isolation valve assembly, to reduce heat transfer from the isolation valve assembly to the pressure sensor assembly.

18. A pressure monitoring assembly comprising:

an isolation valve assembly comprising;

a rigid manifold having a first pressure inlet port, a first pressure outlet port, a second pressure inlet port and a second pressure outlet port;

a first isolation valve adjustable between an opened position in which the first pressure inlet port is in fluid communication with the first pressure outlet port and a closed position in which flow in the rigid manifold from the first pressure inlet port to the first pressure outlet port is stopped;

a second isolation valve adjustable between an opened position in which the second pressure inlet port is in fluid communication with the second pressure outlet port and a closed position in which flow in the rigid manifold from the second pressure inlet port to the second pressure outlet port is stopped;

an equalization connection formed in the rigid manifold permitting fluid communication between the first pressure outlet port and the second pressure outlet port through the rigid manifold;

an equalization valve adjustable between an opened position permitting fluid communication through the equalization connection between the first pressure outlet port and the second pressure outlet port and a closed position sealing the first pressure outlet port from the second pressure outlet port;

a pressure sensor assembly comprising;

a first pressure sensor port; and

a second pressure sensor port rigidly secured relative to the first pressure sensor port;

a first pressure tight attachment mechanism for releasably securing the first pressure outlet port to the first pressure sensor port in rigid alignment and in a pressure tight manner;

a second pressure tight attachment mechanism for releasably securing the second pressure outlet port to the second pressure sensor port in rigid alignment and in a pressure tight manner;

wherein the isolation valve assembly and the attached pressure sensor assembly have an internal length of fluid connections past the first and second isolation valves which is less than fourteen linear inches, and without a bleeding valve.