ANSI/FCI 99-2-2015 pdf free download
ANSI/FCI 99-2-2015 pdf free download.AMERICAN NATIONAL STANDARD PRESSURE REDUCING REGULATOR CAPACITY.
4.1 Suggested test set up and equipment is shown in Figure 1. Assure that all equipment has flow and pressure ratings equal to or greater than that expected in the test. Test set up can be per ISA 75.02.01 and ANSI B109.4. Accuracy of Instruments is also covered in these standards. 4.2 Insure the Flow Meter is installed in accordance with the manufacturer’s recommendations. Note that the Flow Meter can be located anywhere in the flow stream. 4.3 Use appropriate size conduits and fittings to connect the test unit in the test stand to prevent conduit flow restrictions from adversely influencing the test. 4.4 Pressure taps P1 and P2 to be located in the test setup as defined in Figure 2. 4.5 Assure that the test fluid is properly filtered before it enters the test stand to protect test regulator and instrumentation. 4.6 With the supply valve and downstream throttling valve closed, install the pressure regulator to be tested. 4.7 Adjust the supply pressure of the fluid source to that required for the test. 4.8 Open the supply valve and assure there are no leaks in the setup. Verify the primary pressure, P1, is correct and maintained during the test. 4.9 Adjust the pressure regulator to be tested to the test setpoint. Adjustments to the downstream throttling valve may also be required to position the setpoint at a minimum controllable flow. 4.10 Beginning with the downstream throttling valve closed, proceed to open the downstream throttling valve in a number of incremental steps to produce various flow rates through the test pressure regulator. Verify the primary pressure, P1, is maintained during the test.
4.11 Produce sufficient incremental flow rate steps to obtain a factual representation of the test regulator’s performance. Closely spaced data points will be required in the low flow region and high flow region for accurately determining lockup, minimum controllable flow, and maximum flow capacity. 4.12 Record the pressures P1, and P2, temperatures T1, and T2, and flow rate for each incremental increasing step in throttle valve opening. 4.13 Calculate the flow rate from the recorded data of flow, pressure, and temperature. 4.14 From the recorded and calculated data, plot a performance curve of the secondary pressure vs. flow rate through the regulator. 4.15 Establish the desired accuracy of regulation and measure the rated capacity at that point. 4.16 Minimum controllable flow, lockup, and maximum capacity can also be determined from the performance curve. (see Figure 3) 4.17 If desired, repeat steps 4.5. thru 4.11. for additional representative setpoints in the units regulating range from which a family of performance curves can be generated.
2. SCOPE To provide a test methodology for measuring and reporting the capacity of pilot operated and direct acting pressure reducing regulators. 3. DEFINITIONS 3.1 Accuracy of Regulation. The deviation from the set point, expressed as a percentage or as a fixed unit, taken at the test conditions. 3.2 Controlled Variable. The variable which shall be monitored by the controlling process. This variable is either the outlet pressure or the differential pressure. 3.3 Lockup (Dead End Shutoff). The deviation of the controlled variable from set point obtained at a no flow condition. 3.4 Maximum Capacity. The flow rate at maximum travel generally used for safety or relief valve sizing. 3.5 Maximum C v . Maximum C v is C v at maximum capacity calculated per ISA S75.01 generally used for safety relief valve sizing. 3.6 Minimum Controllable Flow. The lowest flow rate, at a given set point and temperature, at which a steady regulated condition of the controlled variable can be maintained. The minimum controllable flow is essentially zero for some regulators. Minimum controllable flow is used to determine turndown or rangeability. 3.7 Offset. The deviation of the controlled variable measured as the flow varies from the minimum controllable flow to the rated capacity. Offset is sometimes referred to as droop for pressure reducing valves. 3.8 Rated Capacity. The rate of flow obtainable through a regulator, for specified inlet and outlet conditions and fluid, at a specified offset or accuracy of regulation. 3.9 Rated C v . Rated C v is measured at rated capacity as calculated per ISA S75.01. 3.10 Rated Rangeability (Turndown). The rated capacity divided by the minimum controllable flow, usually expressed as a percentage.
