General Description

CRDG horizontal Multi-stage boiler feed pump can delivery clear water without solid particles or other liquid which the physical and chemical feature is similar with clear water. It is suitable for boiler feed water or deed water for high pressure boiler. The temperature range of the liquid is from -20℃to150℃, and the inlet pressure is not allowed more than 0.6Mpa.

Performance range  
Capacity : 3.75~ 288m3/h
Head :  50 ~ 1540m
 
Instruction of pump type
For Example  CRDG25-80X10

CR: Company Code, means produced by CREDO PUMP

DG — Single-suction, multi-stage, boiler feed pump.
25 — Pump capacity 25 m3/h.
80 —Single-stage head of pump 80m .
10 — pump stage number is 10.

 
Structure
CRDG series pump is single casing segmental multi-stage centrifugal pump, the main parts is stator, rotor, bearing and shaft.

Stator part: it mainly consists of suction stage, mid-stage, discharge stage and diffuser; they are strained through a lever and form a working chamber. The inlet and the outlet are vertical upward. The combined surface between each stage is sealed through metal surface and also with sealing o-ring as auxiliary seal.

Rotor part: it mainly consists of shaft, impeller, and balance drum and shaft sleeve. Shaft transfers power to impeller and make it work. The axial force is balanced by balance disc and there is rechargeable shaft sleeve to protect shaft.

Bearing part: It mainly consists of bearing body, shaft cover and sliding bearing. There are two single centripetal ball bearings in bearing body to prevent balance disk from abrasion. The sliding bearing is lubricated by dilute oil, there is cooling chamber in bearing body and the bearing can be cooled with exterior water.

Shaft seal part: shaft seal uses soft packing seal. It mainly consists of seal box, packing, packing ring and packing cover. The shaft is sealed, cooled and lubricated by exterior water from seal chamber. The mechanical seal can also be used as requirement and it need be cooled, lubricated and washed by exterior water.

 Drive: Pump is directly driven by motor through flexible coupling. View from motor end, the rotating direction of pump is clockwise.

Material of main parts   
The medium-contacting parts are made of cast iron .