AU2006252065B2

AU2006252065B2 - Dual Actuation Valve

Info

Publication number: AU2006252065B2
Application number: AU2006252065A
Authority: AU
Inventors: Brian Ruffles; Leigh Waldon
Original assignee: ETI FIRESYSTEMS P/L
Current assignee: ETI FIRESYSTEMS P/L
Priority date: 2006-12-15
Filing date: 2006-12-15
Publication date: 2014-11-20
Anticipated expiration: 2026-12-15
Also published as: AU2006252065A1

Abstract

Abstract A valve designed to actuate by pneumatic pressure either be receiving a direct pressure signal at the rise of pressure port "ROP PORT", or by releasing pressure direct from actuation chamber. The valve has a gland separating an actuation chamber and a discharge chamber and the gland has a small clearance on a stem of a differential piston. This clearance allows pressure to be equalized in the two chambers. The piston in the discharge chamber is slightly smaller than the piston in the actuation chamber, and can be positioned to effectively seal an inlet port from an outlet port of the discharge chamber. The valve also has a safety burst disc which protects the system against over pressure by monitoring the pressure on the inlet port. When the system is actuated it switches to protecting the ROP actuation system against over pressure.

Description

Field of Invention The present invention relates to a valve designed to actuate by pneumatic pressure either be receiving a direct pressure signal at the rise of pressure port "ROP PORT", or by releasing pressure direct from actuation chamber. Background Heavy mobile and stationary machinery represent substantial investments. Loss of this equipment, production and subsequent danger to the associated personnel is ever-present. Whilst mining is perhaps the major application for the ETI fire system, there are a multitude of other applications including, forestry, construction, power generation and marine equipment operating in harsh environments inside, outside, underground and at sea. The installation of a fire detection and suppression system is essential to minimise the risk to both operator and equipment, and is a mandatory requirement in many of the states of Australia. With many modern vehicle or equipment designs, the operators are often positioned well away from the location of the fire risk. Modern cabs are well insulated from noise and temperature, and operators may not be aware of the presence of fire in their equipment until it is beyond the control of normal portable fire extinguishers. Faced with these dangers operators can and do panic and in most cases abandon the equipment rather than undertake first aid fire protection. 1 Field experience had shown the need for improvement over earlier Dry Chemical Powder suppression systems. These systems generally suffered from compaction of the powder, and often resulted in less than efficient operation. Similarly, the release of a large cloud of chemical powder contributed substantially to the operators visibility and ability to escape as well as serious respiratory difficulty due to inhalation. The advantage of Aqueous Film Forming Foam over gaseous, dry chemical powder and vapourising liquid systems is their ability to control fire after the discharge is complete, to cool hot spots preventing re-ignition and to flow with the fuel spills underneath the vehicle. There are valves used in the fire protection of mobile and transportable equipment that work on a Rise of Pressure (ROP) principle to operate the valve and fire system. There are valves used in the fire protection of mobile and transportable equipment that work on a Loss of Pressure (LOP) principle to operate the valve and fire system. Summary of the Invention The present invention provides a valve for a fire suppression system comprising: (i) an inlet port; (ii) a discharge port; 2 (iii) a rise of pressure (ROP) port; (iv) a loss of pressure (LOP) port wherein the system operates both from the ROP or LOP ports concurrently. Preferably, the valve further comprises an actuation chamber and a discharge chamber wherein a gland separates these two chambers. Preferably, the valve further comprises a differential pressure piston wherein the piston in the discharge chamber is slightly smaller than the piston in the actuation chamber. Preferably, the gland has a smaller clearance around the stem of the differential piston. Preferably, the valve further comprises a safety burst disc. Brief Description of Drawings Figures 1 and 1A show the valve in its normal position, as an embodiment of the present invention Figures 2 and 2A show the valve in its open or actuated position, as an embodiment of the present invention Figures 3 and 4 show the loss of pressure (LOP) port, as an embodiment of the present invention. 3 Description The present invention provides a valve for a fire suppression system concurrently connectable to both a rise of pressure (ROP) port or inlet and loss of pressure (LOP) port or inlet. Thus, the present invention provides a dual valve which is the only valve that operates both from ROP or LOP inputs. The dual valve uses the LOP detection in the critical fire risk area for fast detection and constant system supervision, and the positive and reliable pneumatic pulse of ROP from the manual actuators thereby greatly reduces the risk of system leaks and prohibitive unscheduled downtime. Both types of system operation can be connected to one valve to work concurrently. Either a loss of pressure or rise of pressure will operate the valve. The valve according to the present invention, the ETI valve, is unique in two features. Firstly, it is designed to actuate by pneumatic pressure either by receiving a direct pressure signal at the rise of pressure port "ROP PORT", or by releasing pressure direct from actuation chamber. This capability allows different actuating devices to be connected to it concurrently that either send a pressure actuating signal or actuate by releasing pressure. Figures 1 and 1A show the ETI valve in its normal state. The gland separating the 4 actuation chamber and the discharge chamber has a small clearance at the stem of the differential piston. This allows the pressure to be equalized in the two chambers. The piston in the discharge chamber is slightly smaller than the piston in the actuation chamber. With equal pressure, a slightly higher force applies on the piston towards the actuation chamber until reaching the plug stop. The piston in the discharge chamber then effectively seals the inlet port from the discharge port and prevents leaking. The valve can be actuated by either receiving a direct pressure signal in the ROP port or by a release of pressure from the actuation chamber. The second unique feature is the safety burst disc. In the normal condition in figure A, this safety relief valve protects the system against over pressure by monitoring the pressure on the inlet port. When the system is actuated it switches to protecting the ROP actuation system against over pressure. See Figures 2 and 2B. The drawing as shown in Figure 3 shows the Loss of Pressure Port. Also, the gland is the unique feature that divides the discharge chamber to create a Loss of Pressure (LOP) actuation chamber in addition to the existing Rise of Pressure (ROP) chamber, thus allowing the valve to work in both modes of operation concurrently. Advantages The unique ability of the valve to operate concurrently offers the customers many benefits. The fire system can be designed to best combination of fire detection and manual actuation devices, regardless of the mode of operation. This unique feature 5 allows the designer to design the system with the highest fire detection and actuation performance and also eliminating many troublesome characteristics of fire systems that are locked in the use of only one type of actuation. Notes of Figure 3 LOP and ROP Actuation 5 1) For systems that rely on rise of pressure to actuate. The vent plug at item 7 is removed and replaced with a check valve nipple. Devices such as Rise of pressure Fire Sensors and/or Rise of pressure manual C02 type actuators can be connected to cause actuation in the ROP actuation chamber. 2) For systems that rely of loss of pressure to actuate, devices such as loss of .0 pressure fire sensor tube and loss of pressure manual actuators can be connected to the nipple at item 2. Any of these devices which creates a sudden pressure loss causes that chamber to contract and actuate the valve. 3) Both ROP and LOP devices can be connected at the same time. Sec X-X Normal .5 Showing the valve in the normal pressurized and closed position. The ROP chamber has no pressure because nothing has actuated the valve. The LOP chamber is pressurized to the same as the cylinder it is attached to. Pressure introduced to the ROP chamber will actuate the valve. A sudden pressure drop in the chamber will also actuate the valve. 20 Sec. X-X Actuated Showing the valve in the actuated and open position. The ROP chamber has expanded. The LOP chamber has contracted. Pressure introduced to the ROP chamber causes expansion. A sudden pressure drop in the LOP chamber will cause contraction. Either process or both together will actuate the valve. 6

Claims

1. A system for fire suppression comprising: (i) an inlet port; 5 (ii) a discharge port; (iii) a rise of pressure (ROP) port; (iv) a loss of pressure (LOP) port; and (v) a dual valve wherein the inlet and discharge ports are disposed at opposite ends and the dual .0 valve is the only valve that actuates both from ROP or LOP ports.

2. The system according to claim 1 further comprising an actuation chamber and a discharge chamber wherein a gland separates these two chambers.

3. The system according to claim 2 further comprising a differential pressure piston wherein the piston in the discharge chamber is slightly smaller than the 15 piston in the actuation chamber.

4. The system according to claim 3 wherein the gland has a small clearance around a stem of the differential piston.

5. The system according to any one of claims 1 to 4 further comprising a safety burst disc. 7

6. The system according to any one of claims 1 to 5 wherein the valve is closed under normal, unactuated conditions.

7. The system according to any one of claims 1 to 5 wherein the valve is open under actuated conditions. 5

8. The system according to any one of claims 1 to 7 wherein the valve is actuated by either receiving a direct pressure signal in the ROP port or by a release of pressure from the actuation chamber. 8