BS ISO 6182-6:2015 pdf free
BS ISO 6182-6:2015 pdf free.Fire protection一Automatic sprinkler systems一Requirements and test methods for check valves
Prior to conducting this test the minimum opening pressure of the valve needs to be determined.With the valve in a normal working position and the sealing assembly in the closed position, a hydrostatic pressure of 0,35 MPa (3,5 bar) shall be applied to the outlet end of the valve for a period of 90 days.During this period, the water temperature shall be maintained at 87±2 °C by an immersion heater or other suitable heating device. Provisions shall be made to maintain the water in the inlet end of the valve at atmospheric pressure.
Upon completion of this period of exposure, the water shall be drained from the valve and the valve shall be allowed to cool to ambient temperature for at least 24 h. With the outlet end of the valve at atmospheric pressure, a hydrostatic pressure of 0,035 MPa (0,35 bar) above the minimum opening pressure shall be gradually applied to the inlet end of the valve. The sealing assembly shall move off the seat and no piece of the seal, other than colour shall adhere to the mating surface.
Where the same design of a seal is used for more than one size of valve, only a sample of the size with the highest stress on the seating surface shall be tested.
Install the valve in a test apparatus using piping of the same nominal diameter. Use a differential pressure-measuring device accurate to±2 % of value.
Measure and record the differential pressure across the valve at a range of flows above and below the flows as specified in 4.12. Replace the valve in the test apparatus by a section of pipe of the same nominal size and measure the differential pressure over the same range of flows. Using graphical methods, determine the pressure drops at the flows. Record the hydraulic friction loss as the difference between the pressure drop across the valve and the pressure drop across the replacement pipe.
Equivalent length of the valve (provided in meters of pipe) shall be calculated based on the nominal size of the valve and pipe specification referenced in the manufacturer s installation instructions.BS ISO 6182-6 pdf download.