Centrifugal Horizontal Pumps
6Pages

MECHANICAL SEAL The NH series standard horizontal axis centrifugalpumps are of the Γprocess design type.They comprise 2 assemblies :ԕ the first including the body (A) and its frontflange (G) and rear flange (H). the second including the bearing-frame (V) fittedwith the impeller (B) and the rear flange plate (C).This design, and the fact that the coupling is fittedwith a spacer part, allow easy dismantling of the second assembly to access the impeller (the first assembly remaining fixed to the baseplate and to the suction and discharge pipes). Under these conditions, it is no longer necessary to dismount and realign the motor.The discharge orifice is located on the pump axis,making pipework connection and design particu- larly easy. Pumps are fitted with open or closed impellers depending on the required flow rate characteristics and discharge head. For open impellers, the correct clearance at the front (between impeller vanes and body) is obtained by adding or removing spacer washers.The shaft is sealed by installing standard CARBONE LORRAINE Փsingle or ԓdouble type seals (see diagram below). Other types of seals can also be supplied (see section ԓOptions).The bearing-frame is reinforced. It contains twobearings : roller on the pump side, and double row of oblique contact balls on the motor side.Bearing lubrication by grease allows up to1500hours of operation without the addition of grease (except in the largest model which is oil lubricated).The shaft has a slight offset which eliminates ben-ding and vibration, thus enlarging the lifetime of the seal and the roller bearings.The shaft end is standardised to NF E 44121/DIN 24256/ISO 2858. Design >

Single seals Carbon/Carbon or Silicon Carbide/Silicon CarbideAll pump types as indicated in the table on page 6 except NH 200-150-400 Օ Carbon/ceramicPump types NH 200-150-400 Viton rings Fixed GRAPHILORor CSi sleeveRotating GRAPHILORor CSi sleeveDrive pin Fixed sleeveholding rod SpringHousing Viton rings GRAPHILORrotating sleeve Drive pinFixed ceramicsleeveHousing Spring > 2 size="-1">

Pump types are identified as shown in theexample below :An identity plate, shown below, is fixed to all ourpump models : NH 50 32 ֖ 125 Nominal diameterof the suction orificeNominal diameterof the discharge orificeStandardisedtype withhorizontal axisNominal diameterof impeller > The range of GRAPHILOR horizontal centrifugal pumps includes 23 different pump types. Each can be fitted with different impeller diameters. This covers flow rates up to 500 m > 3 /h and atotal discharge head which can exceed 60 mdepending on the flow and rotation speed consi- dered (1,450 or 2,900 rpm). 1 450 rpm >...

2 900 rpm > Total discharge head (m) Flow rate (m > 3 /h) Note :To select and size pumps, use curves on the individual specification sheets listed on page 6. > Hydraulic test of the pump body depending onthe type selected.Օ Systematic tests :. flow rate . total discharge head . power absorbed. Tolerances comply with test standard NF X10601 Appendix B : ՓMass produced pumps, namely : . flow rate : Ա8 % . total discharge head : 8 % . Power absorbed : + 8 %ѕ On request : (with extra charge). required NPSH. Seal type :- FLEXIBOX single - FLEXIBOX double - PACIFIC single - PACIFIC double - CRANE...

On request, horizontal GRAPHILOR centrifugalpumps may be supplied with : coupling, Օ cast iron base plate : standard NF E 44131, motor : unless mentioned otherwise, our standardmotors are mounted in accordance with standard NF 51-115, protection IPW 55 for chemical industries (on request : series R explosion proof motors).These information must be stated on the order. When the pump is delivered with its couplingonly, the motor side sleeve is not bored (except when requested). ՕPumped fluid : nature, ֖ temperature, density, ֖ viscosity, vapour pressure.֕Required performances : flow rate, ֖...