grundfos Water Treatment DMH DMH Hydraulic Piston Diaphragm Dosing Pumps from 0.15 l/h up to 2 x 1500 l/h (200 to 4 bar) General The Grundfos DMH range is a series of extremely strong, robust pumps for applications requiring a reliable dosing and high-pressure capability, such as process engineering. The range is highly versatile: it covers a wide flow range and offers a variety of dosing head sizes, materials and accessories. Accurate dosing - all the time DMH pumps have a very high dosing accuracy and allow an exact reproducibility. • For DMH25x, the dosing flow fluctuation is <± 1.5 % within the 10-100 % control range, and the linearity deviation is ± 2 % of the full-scale value. • For DMH28x, the dosing flow fluctuation is <± 1 % within the 10-100 % control range, and the linearity deviation is ± 1 % of the full-scale value. Smooth and low-pulsation dosing The DMH range combines sophisticated drive technology and gear kinematics to ensure smooth and low-pulsation dosing without pressure peaks. This means less stress to all system components and leads to longer service intervals for the entire system. Motors to match application needs For applications with specific motor requirements, the versatile DMH range offers high-quality motors for 50 Hz, 60 Hz, 100 Hz (with Variable Frequency Drive VFD) as well as EX classified or ATEX-certified motors, if required. Perfect material selection - for housing and liquidwetted parts The DMH models have a robust cast-aluminium housing with epoxy coating to meet all application needs (grey castiron if API 675 is required). A wide choice of materials for dosing head, valves and accessories allows selecting exactly the degree of chemical resistance required. All liquid-wetted parts need to be resistant to the chemicals used. The diaphragm is made of full-PTFE material. Safe and trouble-free operation The serially integrated pressure relief valve and active diaphragm protection system (AMS) keep the pump and the entire system protected against overpressure, if the discharge line is blocked. In addition, the degassing valve at the pump guarantees high functional safety of the pump, the installation and the whole process. Due to their aluminium enclosure and the piston diaphragm technology, DMH pumps have a very long operating life and long service intervals. Approvals and certificates For potentially explosive areas we offer EX classified or ATEX-certified motors and pumps. For applications in the petrochemistry we provide DMH dosing pumps with API 675 certificates. Flexibility - in pump configuration and applications A number of different product configurations are available to match requirements: • Flexible control concept for flow rate, manual or automatic stroke-length adjustment with electric servomotor. • Pumps fitted with double diaphragm with failure indication, or special dosing heads with electrical heating. Universal fields of application are possible for this pump series due to the full-PTFE dosing diaphragm. Wetted parts are available in material combinations that suit virtually all dosing tasks. Choose the best configuration for your specific dosing task.

Power plants PP PVDF Stainless steel 1.4571 (EN 10027-2) 316 Ti (AISI) PVC All dosing head materials are also available with diaphragm leakage detection. Petrochemical industry, refinery On request • Stainless steel with electrical heating flange • Stainless steel PTFE-coated • Alloy C-4 (2.4610), EN 10027-2 Gasket Valve ball Glass PTFE Stainless steel, 1.4401 (EN 10027-2) 316 (AISI) Ceramic Treatment of process water and drinking water Ex zones On request • Alloy C-4 (2.4610), EN 10027-2 Valve type Dosing of flammable liquids • Not spring-loaded • Spring-loaded • Spring-loaded, discharge side...