Fire Hose Testing Apparatus and Method

Abstract

A method for testing a plurality of fire hoses having respective service test pressures and the test apparatus therefor wherein each hose is required to maintain a test pressure for a specified duration to pass the test. The test pressure is proportional to the service test pressure. Each hose is coupled to a respective hose fitting of a respective branch test conduit. Each branch test conduit includes an isolation valve, a pressure transducer, and a hose fitting downstream of the isolation valve. A variable frequency-variable speed controls a motor which drives a positive displacement water pump supplying water to and pressurizing a water header conduit and a plurality of branch test conduits interconnected therewith. An algorithm applied to the error signal for a respective hose line generates a pump speed command limited by the controller to regulate the rate of increase of pump output pressure.

1 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, comprising:
 a variable frequency-variable speed drive to control a pump motor;   a positive displacement pump driven by said variable frequency-variable speed drive which controls said pump motor;   a water header conduit;   the positive displacement pump supplying water to and pressurizing said water in said water header conduit during pump operation;   a plurality of branch test conduits interconnected with said water header conduit and receiving water under pressure from said water header conduit;   each of said branch test conduits includes an isolation valve, a pressure transducer downstream of said isolation valve, and a hose fitting downstream of said isolation valve;   each of said hoses coupled to a respective hose fitting of a respective branch test conduit, said hoses receiving water from said branch test conduit and said water header conduit;   each of said pressure transducers measuring pressure in said branch test conduit and said hose;   said isolation valve of each of said branch test conduits being closed when said pressure of each said branch test conduit and said hose is achieved; and,   said isolation valve of each of said branch conduit closes if and when said pressure transducer measures a sufficient pressure loss with respect to time in each of said branch test conduits and hoses during pressurization.   
     
     
         2 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 1  further comprising a pressure reducing valve arranged in series with said positive displacement pump. 
     
     
         3 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 1  further comprising a pressure reducing valve. 
     
     
         4 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 1  wherein said apparatus resides in a vehicle trailer. 
     
     
         5 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 2  wherein said apparatus resides in a vehicle trailer. 
     
     
         6 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 3  wherein said apparatus resides in a vehicle trailer. 
     
     
         7 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 1  further comprising a controller, said controller controlling said variable frequency-variable speed drive which controls said pump motor and limits the rate of pressure rise or fall in each of said branch test conduits. 
     
     
         8 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a pressure for a specified duration as claimed in  claim 7  further comprising a controller, said controller controlling the position of said isolation valve. 
     
     
         9 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a pressure for a specified duration as claimed in  claim 7  wherein said controller compares the pressure of each of said hoses to the actual pressure in each of said hoses as measured by said pressure sensor of each of said branch test conduits generating an error signal, said controller generating an output signal, and, said output signal is the sum of: a first proportional constant times the error signal plus a second proportional constant times the integral of the error signal plus a third proportional constant times the derivative of the error signal. 
     
     
         10 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 7  wherein said apparatus resides in a vehicle trailer. 
     
     
         11 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 8  wherein said apparatus resides in a vehicle trailer. 
     
     
         12 . A fire hose testing apparatus for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 9  wherein said apparatus resides in a vehicle trailer. 
     
     
         13 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, comprising the steps of:
 coupling each of said hoses to a respective hose fitting of a respective branch test conduit, each of said branch test conduits includes an isolation valve, a pressure transducer downstream of said isolation valve, and a hose fitting downstream of said isolation valve;   inputting specified pressures (set points) into said controller for each of said hoses;   starting a variable frequency-variable speed pump drive which controls a pump motor;   driving a positive displacement water pump with said variable frequency-variable speed drive motor;   supplying water to and pressurizing a water header conduit during operation of said positive displacement pump;   supplying water to and pressurizing said plurality of branch test conduits interconnected with said water header conduit, said hoses receiving water from said branch test conduit and said water header conduit:   inputting the actual line pressure sensed from each of said pressure transducers downstream of said respective isolation valve of each of said branch test conduits into said controller;   generating pressure error signals by subtracting said respective actual line pressures of each of said respective pressure transducers from said respective specified pressures;   applying an algorithm, using said controller, to each of said error signals and outputting a respective pump speed command beginning with said branch test conduit having the lowest specified pressure;   limiting the rate of change of the pump speed;   closing said respective isolation valve of said branch test conduit for said lowest specified pressure when said actual line pressure is greater than or equal to said specified pressure;   using said controller, outputting a respective pump speed command beginning with said branch test conduit having the next lowest specified pressure,   limiting said rate of change of said pump speed; and,   closing said respective isolation valve of said branch test conduit for said next lowest specified pressure when said actual line pressure is greater than or equal to said specified pressure.   
     
     
         14 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 13 , wherein said steps of:
 outputting a respective pump speed command with respect to said branch test conduit having a pressure;   limiting the rate of change of the pump speed;   closing said respective isolation valve of said branch test conduit for said pressure when said actual line pressure is greater than or equal to said specified pressure;   are performed repeatedly and successively for each branch test conduit from the lowest specified pressure to the highest specified pressure.   
     
     
         15 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 13  further comprising the steps of:
 stabilizing each of said branch test conduits and said hoses coupled thereto; and, 
 opening said respective isolation valves and boosting the pressure, if necessary, of one or more of said respective branch test conduits and said hoses coupled thereto if said actual line pressure is less than the service test pressure of said hose. 
 
     
     
         16 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 13 , further comprising the steps of:
 closing said respective isolation valve of said branch test conduit when said actual pressure as sensed by said respective pressure transducers is sufficiently reduced with respect to time.   
     
     
         17 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 14 , further comprising the steps of:
 closing said respective isolation valve of said branch test conduit when said actual pressure as sensed by said respective pressure transducers is sufficiently reduced with respect to time.   
     
     
         18 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a specified pressure for a specified duration, as claimed in  claim 15 , further comprising the steps of:
 closing said respective isolation valve of said branch test conduit when said actual pressure as sensed by said respective pressure transducers is sufficiently reduced with respect to time.   
     
     
         19 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a specified pressure for a specified duration, as claimed in  claim 13  further comprising the steps of:
 stabilizing each of said branch test conduits and said hoses coupled thereto if said actual line pressure is greater than or equal to said service test pressure; 
 monitoring actual pressure in each line; and, 
 passing or failing said test depending on whether said actual pressure in each line being is greater than or less than said test pressure. 
 
     
     
         20 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 14  further comprising the steps of:
 stabilizing each of said branch test conduits and said hoses coupled thereto; 
 monitoring actual pressure in each hose; and, 
 passing or failing said test depending on whether said actual pressure in each line being is greater than or less than said test pressure. 
 
     
     
         21 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, as claimed in  claim 13  further comprising the steps of:
 marking each of the fittings of said hoses. 
 
     
     
         22 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, said test pressure proportional to the service test pressure, comprising the steps of:
 coupling each of said hoses to a respective hose fitting of a respective branch test conduit, each of said branch test conduits includes an isolation valve, a pressure transducer downstream of said isolation valve, and a hose fitting downstream of said isolation valve;   supplying water to a pressure reducing valve set to regulate pressure at approximately 45 psig;   pressurizing a water header conduit;   supplying water to and pressurizing said plurality of branch test conduits interconnected with said water header conduit, said hoses receiving water from said branch test conduit and said water header conduit;   measuring pressure in each said branch test conduit and said hose; and,   closing said isolation valve of each of said branch test conduit if and when said pressure transducer measures a sufficient pressure loss with respect to time in each of said branch test conduits and hoses during pressurization and/or when a leak is observed in said hose and/or a coupling of the hose.   
     
     
         23 . A method for testing a plurality of fire hoses, each of said hoses required to maintain a test pressure for a specified duration, as claimed in  claim 22  further comprising the steps of:
 marking each of said hose fittings with a bar code.