ESTABLISHING TERMINATION CRITERIA FOR A PARTIAL-STROKE TEST OF A FLUIDICALLY DRIVEN SAFETY VALVE, AND DETERMINING THE WORKING ORDER OF A FLUIDICALLY DRIVEN SAFETY VALVE

摘要

The invention relates to a method for establishing termination criteria for a partial-stroke test of a safety valve, comprising the following steps: a) a partial-stroke test is carried out at a time at which the safety valve is functional; b) the position of the valve element and the pressure in the drive fluid are recorded; c) a first relationship is derived therefrom which relates the position of the valve element and/or the time and/or the pressure of the drive fluid and/or the deviation to one another; d) this relationship is defined as a reference curve for this safety valve; e) a second relationship is defined which has a predefined spacing from the reference curve; f) the following is established as a termination criterion: if the partial-stroke test is repeated for the same valve, and the same data are recorded, and, as with the reference curve, a third relationship is derived from the data, the partial-hub test is thus not successful if the third relationship has a greater spacing from the reference curve than the second relationship.