CEN/TC 197/SC 4 - Rotodynamic pumps

This technical report lays down stipulations relating to installation conditions for sudden change in section or direction (elbows, tee fittings, junctions) and the most widely used accessories at the inlet and outlet of pumps (valves and fittings) in order to minimise the effect of disturbances in the flow of liquid thereby created upstream and downstream from the pump and on the operation of the pump. NOTE The recommandations given in this document permit to solve a majority of the most current cases These recommandations relate to three aspects of installation : - the fitting of the pump to pipework by convergent and divergent pipes ; - in the case of elbows, tees and branchings, their direction with respect to the axis of the pump ; - the minimum clearances to be adhered to between a disturbing (elbow, valve, etc.) and the mounting flange of the pump. This document applies to the installation of rotodynamic pumps (centrifugal, mixed flow and axial flow) fitted in piping. It applies to pumps having intake diameters equal to or less than 500 mm. The recommendations may be
adapted in agreement with the pump manufacturer for intakes having dimensions exceeding 500 mm or for special applications. This document is not applicable to pumps of which the inlet is located in reservoirs, sumps or tanks and which will be dealt with a subsequent standard. The recommendations in this document are only valid under the following conditions : - newtonian fluids having a maximum viscosity of 2.10 -4 m 2 /s ; - occluded gas content at pumping temperature and inlet pressure not exceeding 2 % by volume for water and 4 % for other fluids ; - solids content (small particle size, such as sand) not exceeding 1 % by volume, nor 1 % by weight ; - in piping with diameters D 1 and D 2 (see figure 11), flow rate velocity, should be in the following ranges : - 3 to 5 m/s at inlet ; - 4 to 10 m/s at outlet...(Truncated)

This CEN report provides informations for the calculation of maximum permissible forces and moments allowed on the flanges of various types of horizontal and vertical shaft rotodynamic pumps, caused by the reaction to pipework which is rigidly connected to the installation. This document does not take into account the effect of any elastic or deformable linkages, such as bellows, elastic joints, self butting sliding joints etc. This CEN report is not applicable to multistage monobloc pumps, whose outlets are remote from the installation plane,
or to horizontal shaft pumps mounted vertically for installation reasons, such as, fixing to a vertical wall.

1.1 This technical report contains recommendations for the design of pump intakes and the installation of pumps. As far as possible, these recommendations should be adhered to in order to obtain correct operation of the plant. These recommendations are applicable regardless of the flow rate of the plant : - plant which works with clear water (or relatively uncloudy) and relatively non-aerated water or any other liquid having physical and chemical properties which are similar to those of water ; NOTE This document nevertheless contains several general recommendations for operation with cloudy (or very cloudy) water. - Pumping plant which has its own floor. 1.2 This standard deals with various intake configurations : - clause 3 contains recommendations which apply to vertical intakes with a bellmouth ;
- clause 4 contains recommendations applicable to top intakes ; - clause 5 contains recommendations applicable to floor intakes ; - clause 6 contains recommendations applicable to side-wall intakes.

This draft European Standard establishes general principles for the construction, use and testing of circulation pumps having an electrical power input P1 smaller than or equal to 200 W, intended to be used in heating installations and domestic hot water service installations. The requirements of this European Standard may apply to circulation pumps for domestic use having an electrical power input above 200 W up to and including 300 W. However,this decision depends on agreement between the supplier and purchaser.