UL 448-2020 pdf download

UL 448-2020 pdf download.Centrifugal Stationary Pumps for Fire-Protection Service.
6 Glossary 6.1 For the purposes of this standard, the following definitions apply. 6.2 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. 6.3 PRESSURE, MAXIMUM NET – The maximum net pressure developed by the pump at the rated speed which typically occurs at or near shutoffpressure. 6.4 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. 6.5 PRESSURE, NET (TOTAL HEAD): a) For a split-case, end-suction, in-line pump, multistage multiport, 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 sump 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. 6.6 PRESSURE, SHUTOFF (CHURN) – The net head developed by a pump at rated speed with no water being delivered (discharge valve closed).
6.8 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. 6.9 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. 6.10 PUMP LOAD – The brake horsepower (kW input) required to drive a pump at rated speed and at the capacity requiring maximum power. 6.11 PUMP, MULTISTAGE MULTIPORT – A centrifugal pump with multiple impellers operating in series where the discharge from each impeller, except for the last impeller, provides pressure to the subsequent stage and multiple discharge ports are provided at certain locations within the stages of the pump. 6.12 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. 6.13 PUMP, VERTICAL-TURBINE – A centrifugal pump with one or more impellers discharging into one or more bowls and a vertical eductor or column pipe used to connect the bowls to the discharge head on which the pump driver is mounted. The pump may also be provided with a suction vessel as an integral part. Vertical turbine pumps not provided with suction vessels are intended for installation in sumps or wells.
7.9 Flange dimensions and bolt layouts used in pipe connections shall comply with the requirements of one of the following standards: a) Standard for Cast Iron Pipe Flanges and Flanged Fittings, ANSI/ASME B16.1; b) Standard for Ductile Iron Pipe Flanges and Flanged Fittings : Classes 150 and 300, ANSI/ASME B16.42; or c) Standard for Pipe Flanges and Flanged Fittings: NPS 1/2 through 24, ANSI/ASME B16.5, when steel is used Exception: A pump intended for use in installations where the connection piping has national pipe flange dimensions that are different from these standards shall be permitted to be constructed with flanges complying with the national pipe flange standard compatible with connection piping. 7.10 A threaded opening used for pipe connection shall comply with the requirements in the Standard for Pipe Threads, General Purpose, Inch, ANSI/ASME B1.20.1.UL 448-2020 pdf download.