OEM Horizontal Multi-stage Centrifugal Boiler Circulating Pump

Performance Curve & Parameters Table:

Application: Used for low pressure and intermediate pressure hot water transsportation or high pressure water supply and drainage for the factory and city.

Inlet pressure less than 0.6 MPa,equivelant to 6 bar.

Temperature from -20℃ ~ 150℃

Structure of DG pump:

The series of DG pump inlet and outlet are all vertical upward. The casings of the pump are suction casing, stage casing(s), discharge casing, which bolted by tie bolts. There are two bearing housings, one packing box and other pump stator parts connected with suction casing and discharge casing by bolts.

The rotor part is mainly composed of shaft and impeller(s), shaft sleeve, balance disk and other parts. The numbers of the pump stage is the numbers of impeller which is the numbers of stage casings plus one because there is one impeller installed in the discharge casing. The shaft parts use the flat key and the shaft nut fastening to make it integrated with the shaft. In operation, the rotor will move in the axial direction of the pump casing so you cannot use radial ball bearing. The entire rotor is supported by either end rolling bearing or sliding bearing. The rolling bearings are lubricated with grease while the sliding bearings are lubricated with thin oil and the oil ring for self-lubricated and the circulating water for cooling. The axial force is balanced by the balancing disk, which is generally made of welded hard surfacing alloy, alloy steel or QT600Mn2 alloy. The balancing disk belongs to the vulnerable parts, and should be replaced in time.

During the installation of the suction casing, stage casing and discharge casing, their sealing contact surfaces must be sealed by molybdenum disulfide grease. Between rotor part and stator part is sealed with seal ring, diffuser sleeve etc. Please replace the seal ring and the diffuser sleeve when the abrasion had infOEM Horizontal Multi-stage Centrifugal Boiler Circulating Pumpce on the performance of the pump work.

The seal of shaft has two methods: mechanical seal and packing seal. When the pump adopts packing seal, the placement of the packing ring should be correct, the tightness of the packing must be appropriate, and the liquid can be exuded by drop by drop. By mechanical seal, there is no liquid exuded. All kinds of sealing elements are in the sealed box in which must pass into certain pressure water for water seal, water cooling or water lubrication. The shaft seal is fitted with a replaceable shaft sleeve to protect the shaft of the pump.

The main parts of the pump are usually made of high quality cast iron, or cast steel or stainless steel.

The series pump is driven directly by the prime mover through the elastic coupling, and the pump is rotated clockwise from the prime mover direction.

Production process:

Casting + As-cast + CNC processing + Parts test (Vision inspection + Dimensional measurement + Impeller static equilibrium test) + Casings installation and pressure test + Rotor installation and dynamic balance test + Pump installation + mechanical seal test + Deflection tester for the coupling assembly + Test bed testing + Painting + Packing + Shipment

According to the application, we can offer:

1. D and D (P) types of multistage pumps for clean water transmission. Materials are cast iron parts and 45# Steel shaft. The medium temperature is below 80 degree Celsius. Apply for mining, mill and city water supply and drainage.

2. DF and DF (P) types of multistage pumps for corrosive liquid transmission. Temperature range is from -20 degree Celsius to 105 degree Celsius. According to the liquid features we have 3 types of material general configuration: light corrosive, moderate corrosive and strong corrosive. Apply for mining dewatering, chemical liquid pump, pump for acid washing of boiler etc.

3. DY and DY (P) types of multistage pumps for oil transmission. Temperature range is from -20 degree Celsius to 105 degree Celsius. Apply for petroleum product etc.

4. MD and MD (P) types of wearing resistance multistage pumps for sewage from mining well. Density less than 1.5% and size of particles 0.5mm for MD while 1.5mm for MD (P) types. The medium temperature is less than 80 degree Celsius. Materials usually are ductile iron.

5. DG and DG (P) types of multistage pumps for hot water. Temperature range is from 20 degree Celsius to 150 degree Celsius.