Check valve testing system

Claim 1

Method of testing the operating condition of a fluid flow check valve including a movable check valve disk positioned in a check valve chamber defined by a check valve casting, said method comprising the steps of: removably and temporarily locating a sound wave sending unit and a sound wave receiving unit at the check valve; directing a sound wave at and through the check valve casting and at the check valve disk; receiving a plurality of reflected sound waves from reflection of the directed sound wave off elements of the check valve; generating an isolated signal from the first reflected sound wave which, after a selected delay, subsequent to the directing of the sound wave, has an energy level above a predetermined minimum level, said isolated signal corresponding to a sound wave reflected off the check valve disk,; counting the lapsed time from the end of the selected delay until the generation of the isolated signal; creating a signal corresponding to the lapsed time from the end of the selected delay until the generation of the isolated signal; collecting the signal corresponding to the lapsed time from the end of the selected delay until the generation of the isolated signal; repeating the above directing, receiving, generating, counting, creating, and collecting steps at selected intervals over a period of time; and plotting a lapsed time versus real time curve which reveals changes in position of the check valve disk with respect to real time, whereby the operating condition of the check valve with respect to degradation and wear of check valve elements can be determined and analyzed.