D-type single-suction multistage centrifugal pump and DG-type single-suction multistage boiler feed pump

D-type single-suction multistage centrifugal pump

High efficiency and energy saving: Utilising advanced hydraulic model design, the flow channels of the impeller and guide vanes have been optimised to effectively reduce hydraulic losses and improve pump operating efficiency. Compared to traditional centrifugal pumps, energy consumption can be reduced under the same operating conditions, resulting in significant long-term savings in electricity costs for users.

Compact structure: Featuring a single-suction, multi-stage, segmented design, the pump's impellers are arranged in series, with a rational overall layout that minimises floor space requirements, making it ideal for installation in facilities or equipment rooms with limited space.

Stable operation: The shaft system has excellent rigidity, and the rotor components undergo precise dynamic balancing calibration, ensuring low vibration and noise levels during operation. This guarantees stable performance during long-term continuous operation and reduces the risk of failures caused by equipment vibration.

Wide application range: Suitable for pumping clean water and liquids with physical and chemical properties similar to clean water, with a temperature not exceeding 80°C. It is applicable to various scenarios such as mine drainage, urban water supply and drainage, industrial circulating water systems, and agricultural irrigation.

DG Type Single Suction Multistage Boiler Feed Pump

Excellent high-temperature performance: The pump's flow components are made of high-temperature resistant materials, such as alloy steel for the impeller and pump shaft, which can withstand the erosion and corrosion of high-temperature liquids. It can transport clean water or mildly corrosive liquids with temperatures not exceeding 160°C - 210°C, meeting the high-temperature requirements for boiler feedwater.

Safe and reliable operation: Equipped with a complete shaft sealing device, typically using mechanical seals, which offer excellent sealing performance and effectively prevent high-temperature liquid leakage, ensuring safe pump operation. Additionally, the pump's bearings use forced lubrication or cooling methods to ensure they do not overheat and fail under high-temperature conditions.

Efficient and stable water supply: Designed specifically for boiler feedwater systems, it provides stable head and flow output, ensuring continuous and uniform water supply to the boiler. This prevents fluctuations in water volume from affecting boiler operation, thereby ensuring safe and efficient boiler operation.

Rational structural design: The pump adopts a single-suction, multi-stage, segmented structure with symmetrically arranged impellers in each stage, balancing axial forces, reducing bearing loads, and extending the pump's service life. The pump's inlet and outlet are both vertically oriented, facilitating connection and installation with boiler feedwater pipelines.

D-type single-suction multistage centrifugal pump

Flow rate range: Typically between 5 m³/h and 300 m³/h, with suitable flow rate models available to meet various production requirements, ranging from continuous low-flow delivery to batch delivery at medium flow rates.

Head range: Head can reach 50 m to 600 m, accommodating fluid delivery needs at different heights and distances, and easily handling high-head water supply or drainage scenarios.

Motor power: The motor power is generally 5.5kW - 250kW, which can be matched according to the flow and head parameters of the pump to ensure that the pump operates in the efficient range and provides sufficient power.

DG Type Single Suction Multistage Boiler Feed Pump

Flow rate range: Typically between 10 m³/h and 400 m³/h, capable of meeting the feedwater requirements of boilers of various tonnages, whether small industrial boilers or large power plant boilers, with suitable flow rate specifications available for all applications.

Head range: Head up to 100 m - 1000m, precisely matching the required head based on the boiler's operating pressure and feedwater height to ensure smooth feedwater entry into the boiler drum.

Motor power: The motor power is typically 15 kW to 400 kW, providing powerful support for stable operation of the pump under high-temperature and high-pressure conditions, ensuring stable water supply pressure and flow.

D-type single-suction multistage centrifugal pump

The D-type single-suction multistage centrifugal pump consists of multiple impellers connected in series. The liquid enters the first-stage impeller from the suction chamber. Under the centrifugal force generated by the high-speed rotation of the impeller, the liquid is flung toward the outer edge of the impeller and enters the guide vanes. The guide vanes convert the kinetic energy of the liquid into pressure energy and guide the liquid into the next stage impeller. Through this sequential pressure-increasing process across multiple stages of impellers, the liquid is ultimately discharged from the pump outlet at a high pressure, enabling high-head fluid transportation.

DG Type Single Suction Multistage Boiler Feed Pump

The operating principle of the DG-type single-suction multi-stage boiler feedwater pump is similar to that of the D-type single-suction multi-stage centrifugal pump, both achieving liquid transportation through the serial connection of multiple impellers for pressure enhancement. The key difference lies in its design, which is specifically optimised for handling high-temperature media. Liquid enters the first stage impeller through the pump's suction inlet, is pressurised by the impeller, and then flows into the diffuser. The diffuser converts part of the kinetic energy into pressure energy and guides the liquid into the next stage impeller. Through continuous pressurisation by multiple stages of impellers, the liquid achieves sufficient pressure and is ultimately delivered to the boiler, meeting the boiler's requirements for feedwater pressure and flow rate.

Application scenarios for D-type single-suction multistage centrifugal pumps:

● Mining industry: Used for underground drainage, slurry transportation in ore dressing plants (requires replacement of flow component materials), etc.

● Municipal sector: Pressurised water supply in urban waterworks, sewage lifting in sewage treatment plants, etc.

● Industrial production: Factory circulating cooling water systems, process water transportation, etc.

● Agricultural sector: Large-scale farm irrigation projects, water diversion and drainage at water conservancy hubs, etc.

DG-type single-suction multistage boiler feedwater pump application scenarios:

● Power industry: Boiler feedwater systems in thermal power plants and thermal power plants, providing high-pressure, high-temperature feedwater to boilers.

● Industrial boilers: Steam boiler feedwater for various industrial enterprises (such as chemical, textile, and paper industries), ensuring normal boiler operation.

● Heating systems: Boiler feedwater for district heating boiler rooms, meeting the water demand of heating boilers.

When selecting a D-type single-suction multistage centrifugal pump or a DG-type single-suction multistage boiler feedwater pump, the following factors should be considered:

Properties of the conveyed medium: including medium name, temperature, viscosity, corrosiveness, and solid content. If conveying high-temperature liquids for boiler feedwater, the DG-type is the preferred choice; if conveying room-temperature clean water or similar liquids, the D-type is the appropriate choice.

Flow rate and head requirements: Based on the actual flow rate of the liquid to be transported and the required head in production, refer to the pump's performance parameter table to select a model that meets the operational requirements.

Installation conditions: Consider the size of the installation space, pipeline layout, inlet/outlet pipe diameters, etc., to ensure that the pump's installation dimensions match the on-site conditions.

Operating environment: Consider the size of the installation space, pipe layout, inlet and outlet pipe diameters, etc., to ensure that the pump installation dimensions match the site conditions.

It is recommended to consult with a professional pump equipment supplier before selecting a model, providing detailed operating conditions parameters to obtain more precise selection recommendations, ensuring the selected equipment can operate efficiently and stably.

Daily Inspection: Regularly check whether the inlet and outlet pressure and flow rate of the pump are normal, whether the motor current and temperature are within the specified range, whether there are any leaks in the pump body and pipes, and whether the temperature and vibration of the bearing parts are in good condition.

Lubrication Maintenance: According to the requirements of the equipment manual, regularly add or replace lubricating oil (grease) for the bearings to ensure good bearing lubrication and reduce wear.

Seal Maintenance: Inspect the leakage rate of the mechanical seal. If the leakage rate exceeds the specified value, promptly replace the seal components to prevent medium leakage from causing damage or affecting pump operation.

Impeller and Guide Vanes Inspection: Regularly disassemble the pump housing to inspect the wear and corrosion of flow components such as the impeller and guide vanes. If any damage is found, promptly repair or replace the components to avoid performance degradation due to component damage.

Regular Test Runs: For standby pumps, regular test runs should be conducted to ensure they can be put into use at any time when needed. During test runs, check whether the pump's starting performance and operational sounds are normal.

Through scientific and reasonable maintenance and care, the service life of the pump can be effectively extended, the operational reliability of the equipment improved, the incidence of faults reduced, and the smooth progress of production ensured.