BS EN ISO 10497:2004 pdf free download.Testing of valves – Fire type-testing requirements.
This International Standard covers the requirements and method for evaluating the performance of valves when they are exposed to defined fire conditions. The performance requirements establish limits of acceptability of a valve, regardless of size or pressure rating. The burn period has been established to represent the maximum time require to extinguish most fires. Fires of longer duration are considered to be of major magnitude with consequences greater than those anticipated in the test.
The test pressure during the burn is set at 0,2 MPa(2 bar)for soft-seated valves rated PN 16, PN 25 and PN 40, Class 150 and Class 300, to better simulate the conditions that would be expected in a process plant when a fire is detected and pumps are shut down. In this case, the source of pressure in the system is the hydrostatic head resulting from liquid levels in towers and vessels. This situation is approximated by this lower test pressure.
In production facilities, valves are typically of a higher rating and the pressure source is not easily reduced when a fire is detected. Therefore, for all other valves, the test pressure during the burn is set at a higher value to better simulate the expected service conditions in these facilities.
Use of this International Standard assumes that the execution of its provisions is entrusted to appropriately qualified and experienced personnel, because it calls for procedures that may be injurious to health if adequate precautions are not taken. BS EN ISO 10497:2004 refers only to technical suitability and does not absolve the user from legal obligations relating to health and safety at any stage of the procedure.
BS EN ISO 10497:2004 species fire type-testing requirements and a fire type-test method for confirming the pressure-containing capability of a valve under pressure during and after the fire test. It does not cover the testing requirements for valve actuators other than manually operated gear boxes or similar mechanisms when these form part of the normal valve assembly. Other types of valve actuators (e.g. electrical, pneumatic or hydraulic) may need special protection to operate in the environment considered in this valve test, and the fire testing of such actuators is outside the scope of this International Standard.
Note: For the purposes of this International Standard, the terms “fire type-test and” fire test are synonymous.
4 Test conditions
4.1 Direction and conditions for valves to be tested;
4.1. 1 Symmetric seated valves intended by the manufacturer for bi-directional installation shall be tested in one direction only;
4.1.2 Asymmetric seated valves intended by the manufacturer for bi-directional installation shall be tested by carrying out the burn test procedure twice, once in each direction of the potential installation;
The same valve may be refurbished and re-tested, or another, identical, valve may be tested in the other direction;
4.1.3 Valves intended solely for unidirectional installation shall be clearly and permanently marked as such and shall be tested in the stated direction of installation;
4.1. 4 If the valve being tested is fitted with a gearbox or other such manual device, then only that particular assembly shall qualify. If a valve can be supplied with or without a gearbox, testing with a gearbox fitted shall qualify valves without a gearbox but not the converse;
4.1.5 Valves (and gearboxes ) shall not be protected with insulation material of any form during testing except where such protection is part of the design of the component(s);