UL 448-2007 pdf download

UL 448-2007 pdf download.Centrifugal Stationary Pumps for Fire-Protection Service.
5 Glossary 5.1 For the purposes of this standard, the following definitions apply. 5.2 CORROSION-RESISTANT MATERIAL – A material having resistance to corrosion equivalent to or exceeding that of a brass, bronze, monel, or Series 300 stainless steel alloy. 5.3 PRESSURE, MAXIMUM WORKING – For performance tests specified in this standard, the maximum pressure developed at the pump discharge flange under any condition of intended use determined by the sum of the maximum net pressure developed by the pump and the allowed positive suction pressure . For production tests, this value may be lower, based on the conditions imposed by the particular installation for which the pump is constructed. The maximum net pressure and maximum positive suction pressure that are marked on the pump are those that indicate the acceptability of a pump (the limiting pressures) for an installation. 5.4 PRESSURE, NET (TOTAL HEAD): a) For a split-case, end-suction, or in-line pump, or a vertical-turbine pump in a suction vessel, the algebraic difference in psi (kPa) between pressures measured at the discharge flange and at the suction flange, corrected to the pump centerline and corrected for differences in velocity head at the points of gauge attachment. b) For a vertical-turbine pump in a pump or well, the pressure measured by a pressure gauge attached just beyond the discharge head, corrected for the velocity head at the point of gauge attachment and for the vertical distance from the pumping water level to the center of the gauge.
5.5 PRESSURE, SHUTOFF (CHURN) – The net head developed by a pump at rated speed with no water being delivered (discharge valve closed). 5.6 PUMP, END-SUCTION – A horizontal centrifugal pump characterized by having its suction nozzle on the pump centerline at the opposite side of the casing from the stuffing box and having the face of the suction nozzle perpendicular to the longitudinal axis of the shaft. This type of pump is not intended to be used where a static suction lift is involved. 5.7 PUMP, FIRE – A pump for horizontal or vertical mounting, having rated capacities in accordance with the requirements in the Standard for the Installation of Stationary Pumps for Fire Protection, NFPA 20. 5.8 PUMP, IN-LINE – A centrifugal pump, the drive unit for which is supported solely by the pump, and that is characterized by suction and discharge connections having a common centerline that intersects the shaft axis. This type of pump is not intended to be used where a static suction lift is involved. 5.9 PUMP LOAD – The brake horsepower (kW input) required to drive a pump at rated speed and at the capacity requiring maximum power. 5.1 0 PUMP, SPLIT-CASE – A centrifugal pump characterized by a housing that is split axial or radial to the shaft, and mounted in the horizontal or vertical position. This type of pump is not intended to be used where a static suction lift is involved.
6.7 The maximum combined shear stress for a pump shaft shall not exceed 30 percent of the elastic limit in tension or be more than 1 8 percent of the ultimate tensile strength of the shafting steel used. Compliance with this requirement is to be verified by a review of manufacturers’ stress calculations. 6.8 The impellers shall be dynamically balanced to the G6.3 balance quality grade in accordance with the requirements for pump impellers in the Standard for Mechanical Vibration – Balance Quality Requirements of Rigid Rotors, Part 1 : Specification and Verification of Balance Tolerances, ISO 1 940-1 . Exception: The impellers may be statically (single plane) balanced in accordance with ISO 1 940-1 if the ratio of the maximum outside diameter to the width at the periphery (including the shroud but not including the back vane) is equal to or greater than 6. 6.9 Flange dimensions and bolt layouts used in pipe connections shall comply with the requirements in the Standard for Cast Iron Pipe Flanges and Flanged Fittings, ANSI/ASME B1 6.1 . 6.1 0 A threaded opening used for pipe connection shall comply with the requirements in the Standard for Pipe Threads, General Purpose, ANSI/ASME B1 .20.1 . 6.1 1 A pump shall be provided with the following: a) Automatic air-release valve (self-venting pumps excluded); b) Circulation relief valve (except for engine driven pumps for which engine cooling water is taken from the pump discharge) and;UL 448-2007 pdf download.