CR 13932:2000

Rotodynamic pumps - Recommendations for fitting of inlet and outlet on piping CR 13932:2000

Publication date:   Dec 22, 2003

Scope

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)