Flow compensated pressure control system

• US 5,660,198 A
• Filed: 12/21/1995
• Issued: 08/26/1997
• Est. Priority Date: 12/21/1995
• Status: Expired due to Term

• Current Assignee: Argo-Tech Corporation Costa Mesa
• Original Assignee: JC Carter LLC (Atlas Copco AB)
• Inventors: McClaran, Mark R.
• Primary Examiner(s): Ferensic, Denise L.
• Assistant Examiner(s): Farid, Ramyar M.
• Application Number:
  US08/576,151
• Time in Patent Office: 614 Days
• Field of Search: 137/486, 137/487.5, 137/487, 137/488, 137/2, 137/10, 137/12
• US Class Current: 137/12
• CPC Class Codes: B64D 39/06 Connecting hose to aircraft; Disconnecting hose therefrom
• CPC Class Codes: G05D 16/106 Sleeve-like sensing elements; Sensing elements surrounded by the flow path
• CPC Class Codes: G05D 16/2097 using pistons within the main valve
• CPC Class Codes: Y10T 137/0368 By speed of fluid
• CPC Class Codes: Y10T 137/0379 By fluid pressure
• CPC Class Codes: Y10T 137/7759 Responsive to change in rate of fluid flow
• CPC Class Codes: Y10T 137/7761 Electrically actuated valve
• CPC Class Codes: Y10T 137/7762 Fluid pressure type

Abstract

A control system is provided for monitoring and regulating fluid pressure at a remote and/or potentially hazardous location along the length of a fluid flow conduit, without requiring a pressure sensor device at the remote site. The control system comprises a controller responsive to fluid pressure and flow rate readings taken at a convenient and/or safe location along the length of the flow conduit, to derive fluid pressure at the remote site. The controller provides a display of the derived pressure and/or operates a control valve at the safe site to regulate the pressure at the remote site.

Claims

1. A method of monitoring fluid pressure along the length of a fluid flow conduit, said method comprising the steps of:

detecting the fluid pressure at a first location along the flow conduit and generating a pressure signal representative thereof by means of a pressure sensor;

detecting the fluid flow rate at the first location along the flow conduit and generating a flow rate signal representative thereof by means of a flow rate sensor;

deriving the fluid pressure at a second location along the flow conduit remote and downstream from said first location by means of a controller responsive to the pressure and flow rate signals;

said deriving step comprises using said controller to solve the equation;

P2=P1-(Q² ρ

/Cv² *62.4),

Where;

P2=derived pressure at second location

P1=detected pressure at first location

Q=detected flow rate

Cv=system flow coefficient

ρ

=fluid density;

determining the system flow coefficient (Cv) by detecting the fluid pressure and flow rate at the first location while also detecting the fluid pressure at the second location during a simulated operation calibration phase;

means to regulate the fluid pressure along the flow conduit to maintain the fluid pressure at said second location within a predetermined limit;

said means comprising a pressure control pilot valve that is mounted along the flow conduit at least slightly upstream from said first location and further including the step of operating said pressure control valve by said controller to maintain the fluid pressure at said second location within the predetermined limit.

2. The method of claim 1 further including the step of displaying the derived fluid pressure at said second location.