The DMH hydraulic piston diaphragm proportioning pump has a flow rate of 0.15 l/h to 2 x 1500 l/h and a pressure range of 200 to 4 bar
The Grundfos DMH series provides reliable dosing and high voltage carrying applications, such as processing workflows
For a powerful and durable series of water pumps. The DMH 28X is designed for high-pressure applications ranging from 50 to 200 bar. This series of products has high versatility: it covers various flow ranges and provides various proportioning head sizes, materials, and accessories. DMH water pump users around the world have not experienced any malfunctions in their years of operation.
Always accurately proportioning.
The DMH water pump has extremely high accuracy in dosing and has * reproducibility. The dosage flow fluctuation of FDMH25x is less than ± 1.5, with a control range between 10-100%, and a linear deviation of ± 2% of the full-scale value. The dosage flow fluctuation of DMH28x is less than ± 1.0, with a control range between 10-100%, and a linear deviation of ± 1% of the full-scale value.
Smooth and low pulsation dosing
The DMH series combines complex driving technology with gear dynamics to ensure smooth and low pulsation dosing without pressure peaks. This can reduce the pressure on all system components, such as pipelines and valves, and extend the maintenance cycle of the entire system.
The electric motor meets the application requirements
For applications with specific motor requirements, this universal DMH series product can provide high-quality 50Hz, 60Hz, and 100Hz motors (with variable frequency drive VFD), as well as EX level or ATEX certified motors according to requirements.
Complete material selection, suitable for shells and liquid wetted parts
The DMH series products have durable cast aluminum shells and resin coatings that meet various application requirements (grey cast iron if API 675 is required). Maintain low investment and operating costs for many years. Multiple proportioning head materials, valves, and accessories can accurately select the required level of chemical resistance. All liquid wetted components need to be resistant to the chemicals used. The membrane is made of all PTFE material.
Safe and trouble free operation
A continuously coordinated pressure relief valve and active diaphragm protection system (AMS) can protect the water pump and the entire system from overpressure in the event of a blockage in the discharge pipeline. In addition, the exhaust valve of the water pump can ensure the high functional safety of the water pump, installation, and the entire process. Thanks to its aluminum casing and piston diaphragm technology, the DMH water pump has a long service life and maintenance cycle.
Approval and Certification
For areas with potential risks, we offer EX grade or ATEX certified motors and pumps. For petrochemical applications, we offer a special version of API 675 certified DMH dosing pumps.
Flexibility in pump configuration and application.
Various product configurations meet different needs. Flexible control concept of flow rate: manual or automatic stroke length adjustment and servo motor. The water pump is equipped with a dual diaphragm with fault indication or a metering head with electric heating. Thanks to the full PTFE dosing film, this water pump series can be used in all application fields. Wet components can be used for material combinations suitable for all dosing tasks. Choose more for your specific dosing task
Excellent configuration.
Suitable for harsh application environments
power plant
The dosage of various chemicals in all stages of the power plant:
For the treatment of boiler water supply, cooling water, and process water (purified unpurified water, chemicals used in ion exchangers, supplementary water treatment methods, effluent neutralization treatment).
The dosage of ammonia, hydrazine, and phosphate in high-pressure areas (boiler water supply).
Petrochemical/Oil and Gas Industry, Refining
Chemical dosage in oil and gas production and processing areas (excluding drilling and platforms):
Chemical dosage for handling clean water and process water
The dosage of wax used as lubricating oil in oil pipelines
Dosage of inhibitors and anti-corrosion chemicals to protect oil pipelines
Dosage of additives and catalysts
Adding odor to natural gas for safety reasons of leakage
Treatment of process water and drinking water
Harsh environment (hot climate, desert, outdoor installation)
Large flow rate and pressure level
EX area
ATEX Directive (94/9/EC), Group 2, Category 2 (Region 1/21) and
ATEX Directive (94/9/EC), Group 2, Category 3 (Region 2/22)
Combustible liquid dosage

Dosage of ethanol or methanol in wastewater treatment

Coal and gasoline cleaning in mechanical engineering and airport areas