API SPEC 6FC:2009 pdf download

API SPEC 6FC:2009 pdf download.Specification for Fire Test for Valves with Automatic Backseats.
3.1.8 Immediately determine the amount of water collected in calibrated container (Item 19) to establish total through valve seat leakage. Continue collecting water in the calibrated container (Item 19) for use in establishing the external leakage rate. If the test valve is of the upstream sealing type, the volume of water that is trapped between the upstream seat seal and the downstream seat seal, when the valve is closed, shall be determined before the test is started and identified in the test report. It is assumed that during the test this volume of water would move through the valve, past the downstream seat seal and be collected in the calibrated container. Since this volume has not actually leaked past the upstream seat seal, it may be deducted from the total volume measured in the downstream calibrated container when determining the through valve leakage.
NOTE If the total volume collected downstream during the burn and/or cooldown is less than the body cavity volume, the through leakage can be assumed to have been zero.
3.1.9 Cool the valve (or allow to cool) to 212 °F (100 °C) or less. Record reading on sight gauge (Item 4), and calibrated container (Item 19). Cooling may, at the manufacturer’s option, be natural or forced.
3.1.10 The following low-pressure test is required only for API 6D valves with ratings of Class 600 and lower. Decrease the test pressure to the low test pressure value shown in Table 1. Measure the through valve and external leakage over a 5-minute period.
3.1.11 If the step in 3.1.10 was performed, increase pressure on test valve to the high test pressure value in Table 1.
3.1.12 Verify that backseating has occurred by monitoring for (and measuring) leakage at a test port above the backseat, for a period of 5 minutes.
3.1.13 Vent pressure.
NOTE Venting pressure is a change made for safety reasons, and may be omitted at the manufacturer’s option, or for previously-qualified valve designs.
3.1.14 Rework the stuffing box as required. Rework shall be limited to replacement of packing and eutectic washer with parts of the same design and materials. Rework of the stuffing box may include the cleaning out of charred or burnt packing, and light honing or polishing of the sealing area of the stem and stuffing box.
3.1.15 Reapply pressure.
3.1.16 Open the test valve against the high test pressure differential. The valve shall be moved to a partly open (approximately half-way) position. Close the shutoff valve (Item 16). Vent the piping and test valve body cavity to remove air or steam.
3.1.17 Measure and record external leakage for a period of 5 minutes after valve is in the open position at high test pressure.
3.2 Test Adjustments
The stuffing box may be reworked per 3.1.13. No other part of the test valve may be adjusted during the test period. The test system may be adjusted during the test period to keep the test within the limits specified herein.
4.9.3 The nominal size of the test valve is determined by the size of the end connections.
4.9.4 Valves with asymmetric internal or external body construction (exclusive of the end connections), and/or asymmetric seats and closure mechanism, intended for bi-directional installation shall be qualified by conducting the test procedure twice, once in each direction of potential installation. Asymmetric valves intended for single direction installation shall be marked accordingly and shall be tested in the direction of recommended installation.
4.9.5 Valves shall not be protected with insulation material of any form during testing, except where such protection is part of the design of the component.
5 Certification
Records of the test upon which certifications are based shall be available for purchasers review at his request. 6 Safety Considerations
6.1 Personnel Protection
Because of the possible design of the test valve and the nature of the test program, the potential may exist for a hazardous rupture of the pressure boundary components. Protection for test personnel shall be provided.