DMH hydraulically actuated piston diaphragm dosing pumps from 0.15 l/h up to 2 x 1500 l/h, with a pressure range from 200 to 4 bar
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 DMH 28x has been especially designed for high-pressure applications from 50 up to 200 bar. The range is highly versatile: it covers a wide flow range and offers a variety of dosing head sizes, materials and accessories. Customers worldwide have enjoyed years of trouble-free operation from their DMH pumps.
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 <± 1.0 % 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, such as tubes and valves, 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 liquid-wetted parts
The DMH models have a robust cast-aluminium housing with epoxy coating to meet all application needs (grey cast-iron if API 675 is required). Investment costs and running costs for spare parts are kept low over the years: A wide choice of materials for dosing head, valves and accessories allow 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 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 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 petro chemistry we provide special versions of our 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.
Ready for tough application areas
Dosing of various chemicals in all stages in a power plant:
- For boiler feed water, treatment of cooling water and process water (raw water purification, chemicals for ion-exchangers, supplementary water treatment, effluent water neutralization).
- Dosing of ammonia, hydrazine, phosphates in high-pressure areas (boiler feed water).
Petrochemical/oil & gas industry, refinery
Dosing of chemicals in process areas around the production of oil and gas (apart from drilling hole, platform):
- Dosing of chemicals for treatment of cleaning water and process water
- Dosing of wax as lubricant in oil-pipelines
- Dosing of inhibitors and anticorrosion chemicals to protect oil pipelines
- Dosing of additives and catalysts
- Odorisation of gas because of safety aspects in case of leakages
Treatment of process water and drinking water
- Rough environments (hot climate, desert, outdoor installations)
- Higher flow and pressure ratings
- ATEX Directive (94/9/EC), Group II, category 2 (zone 1/21) and
- ATEX Directive (94/9/EC), Group II, category 3 (zone 2/22)
Dosing of flammable liquids
- Dosing of alcohol or methanol in wastewater treatment
- Cleaning of kerosene and petrol in mechanical engineering and airport areas
- Dosing of ethanol and methanol
- Dosing of food-grade alcohol for disinfection in meat and bread packaging
- High pressure dosing up to 200 bar
- Very accurate dosing
- Full PTFE membrane as a standard
Information and advice
Grundfos is a world-wide provider of pumps and related systems. We have a trained staff of service engineers who will be able to support you during the installation phase of the pump or solution. Grundfos products are manufactured to very high standards, which helps to ensure a long life. Our many years of experience of different kinds of installation and with installation techniques are also key factors for maximising the lives of your Grundfos products or systems.
We will be able to support you with the following:
- Information about the proper protection of our pumps
- Advice on the physical positioning of the pump for necessary service/repair
- Advice on the physical positioning of the pump to maintain proper operation
- Correct cabling to fulfil the requirements of good practice and electromagnetic compatibility
Please contact your local Grundfos company to obtain full support for your new installation.
In order to achieve optimum performance, it is very important that the product/system is set up and adjusted correctly from the outset. The knowledge and experience of the Grundfos service technician, and the use of dedicated Grundfos service tools to adjust the performance of the pump, together guarantee that the greatest possible efficiency and fully correct operation of the equipment are both achieved. Commissioning of the pump is recommended in the following cases:
- If the pumps are controlled by a frequency converter
- If the pump system is operating in a large system, e.g. a building management system
- If the user wants to be trained in the proper operation of the pump
- If the pump is a vital link in an important production/application facility
- Where the setup is crucial for the Grundfos product to operate for its full planned life, e.g. in water treatment applications. In such cases commissioning is not only recommended but required
- Where safety is an issue, e.g. in disinfection systems
The commissioning is performed in a step-by-step procedure, and a report of the settings of the pump is produced.
Do not hesitate to contact your local Grundfos company to arrange for the commissioning of your newly-installed Grundfos product.
Recommended spare parts
Even though the Grundfos strategy is to supply the best possible pump solutions to our customers, after a long period of operation there will be wear and tear to some of the components in certain situations. If short operating downtime is a requirement, or if the pump is installed in inaccessible areas where delivery of spare parts may take a long time, it is advisable to maintain a small stock of recommended spare parts on site.
Please contact your local Grundfos company to obtain information about recommended spare parts or service kits for your Grundfos product.
Grundfos offers an efficiency analysis of your existing pump system, providing you with suggestions for increasing efficiency and thus for achieving cost savings over time.
Increase the efficiency of your existing system
Conducting an efficiency analysis of your existing pump system provides you with a basis for increasing efficiency and thus for achieving cost savings over time. An efficiency analysis results in suggestions for increasing efficiency and will show how this will save you money.
Grundfos offers the following levels of analysis for assessing the efficiency of your pump system:
- Installed base checks.
A basic evaluation is carried out purely on the basis of the data from the identification plate on the pump, comparing its performance with that offered by newer, more efficient technology and materials found in modern pumps.
- Pump efficiency quick check.
Pressure and the consumption of the pump in kWh are measured. Flow is estimated on the basis of available pump data and the results of the measurements.
Some of the resulting suggestions for improving efficiency might include a speed control upgrade, a motor upgrade, differently dimensioned pipes, the installation of a controller, or perhaps an agreement for routine service.
Complete pump audit
The efficiency analysis offered by Grundfos makes up the first step in our Pump Audit, a diagnostics tool that we use to check whether the pump system is operating at the optimal energy consumption to guarantee that your costs are kept to an absolute minimum – now and in the future. See "Replacement analysis" to find out more about the Grundfos Pump Audit.
A Grundfos service agreement ensures the efficient and uninterrupted operation of your pump system and gives you access to Grundfos service centres and authorised service partners worldwide, 24 hours a day.
Prevention is better, and more cost-effective, than cure
Once you have purchased your pump, you will want it to function efficiently and reliably; a formal service agreement with Grundfos will give you peace of mind. It also makes sound economic sense, giving you a firm costing for your maintenance budget and access to substantial discounts.
You simply combine a range of service programmes to suit your needs – and then let us carry out scheduled maintenance visits to prevent downtime. We offer three types of service agreement, available for all pumps:
Whichever agreement you choose, your equipment will always be serviced by specially trained staff.
The cost-effective choice
Well-maintained pumps can reduce your energy consumption by up to 50 %. Furthermore, it's worth remembering that in a series of pumps working together, one faulty pump can affect all the others. A Grundfos service agreement keeps the total cost of operating a pump to a minimum. Our careful calculation of the life-cycle cost of all our products means that we have an overview of the true costs of owning each of our pumps.
Signing up for a service agreement and letting our highly-skilled service technicians service your pumps is a safeguard against unforeseen expenditure. Regular servicing and maintenance of your pumps will ensure that they operate with optimum efficiency.
Repair and maintenance
Grundfos Service will maintain and repair your pumps. Our service professionals can also advise you on efficiency issues, offering suggestions for saving money in the long term.
Repair and maintenance of your existing pump systems
Naturally, you can always call Grundfos for the repair and maintenance of pumps you have purchased from us. Grundfos can repair your pumps to the same specifications as new. However, it is important to remember that an upgrade or even a replacement pump can be cheaper than repair in the long term. See "Upgrades and Replacement" for how this makes good business sense.
Effective service – wherever you are
Grundfos Service is always close by. Working in collaboration with our local authorised service partners we offer worldwide service. Help from qualified pump professionals is never far away, whether you need immediate assistance or are interested in hearing about opportunities for making savings.
Grundfos Remote Management
Grundfos Remote Management is a cost-effective, secure and reliable way to monitor and manage pump installations from an Internet PC at a very low cost.
Connecting pumps and people
With a secure and reliable remote management system, you can monitor and manage your pump systems from an Internet PC at a very low cost.
Grundfos Remote Management is a cost-effective and straightforward system for monitoring and managing pump installations in commercial buildings and in water supply and wastewater systems. It reduces the need for onsite inspections, and in the event of an alarm or warning, the relevant people are notified directly.
The system offers a wider range of benefits and functions than mobile-phone-based monitoring. For those who do not require remote process automation, Grundfos Remote Management is the ideal solution for monitoring and remote control, rather than traditional SCADA (Supervisory Control and Data Acquisition) systems. Initial investment is minimal, and a fixed low fee covers data traffic, hosting costs and system support, including back-up of all data.
Efficient alarm management
The on-call schedule in this new telemetry system ensures that alarm messages from onsite controllers go directly to the relevant people. The system manager can log on from a PC anywhere and plan who is to receive alarm messages from each installation at any given time of the day. Managers can plan for years ahead, and can easily handle day-to-day exceptions to the schedule.
Optimise service and maintenance
Changes in pump performance can be tracked using trend graphs generated automatically by the system. This tracking can give an indication of any wear or damage in the installation, and service and maintenance can be planned accordingly.
The communication interface (the CIU271 modem) enables data transmission via GPRS/SMS from your Grundfos pumps and controllers. The built-in multi-purpose I/O board allows you to connect sensors and switches.
The Grundfos Pump Audit is our replacement analysis. It is a complete diagnostic tool that considers your facility, the energy efficiency of your system, and the total life-cycle costs of your pumping solution. It provides detailed recommendations for replacement, including estimated payback time.
Let our Pump Audit tell you how to save on energy costs
Grundfos Pump Audit is the name we give to our replacement analysis This complete diagnostic tool developed by Grundfos is used to identify excessive energy consumption in any kind of pumping system. Our experience with pump audits shows that in many cases, 30-50 % of the energy consumed by pumps could be saved.
The purpose of CAPS is to provide a complete tool that contains both an extensive catalogue of Grundfos products and a sizing program to select the most suitable pump for your application.
There is also a comprehensive pump replacement selection function for central heating circulator pumps, hot water pumps and wastewater S pumps, and a function for producing professional quotations that include curves, drawings, quotation texts, wiring diagrams, etc.
Last but not least, the software contains the instruction and operating manuals for nearly all Grundfos pumps in multiple languages. Service drawings, exploded views and parts lists are available for all sewage products as well as several other pump types.
CAPS is available in two versions: WinCAPS, available on CD-ROM, and the online version WebCAPS, available at the Grundfos website. Additional features in WebCAPS include CAD Drawings and Literature.
"BE Responsible" is one of our core values at Grundfos. It is essential to us that our pumps are designed for low energy consumption and the highest possible performance throughout their operating lives. One consequence of this is that service offerings, including spare parts and replacement kits, are defined in the development phase.
Customised service offerings, online ordering and rapid response distribution centres ensure that you have the parts when you need them.
Recommended Spare Parts List
The list specifies the parts you should keep on site to service your pumps. These recommendations can be found at the product site in our WebCAPS tool.
Specially designed service kits
Service kits include everything you need for a specific maintenance or repair task, including instructions for dismantling, replacement and reassembly.
24-hour spare part delivery service
To be extra sure that you do not have to wait, we can set aside a stock of spare parts that are critical for your operation. This will ensure that they are available whenever you need them.
We guarantee that spare parts for any Grundfos pump you buy today will remain available for at least the next 10 years.
Service online tool
24-hour access to our online tool WebCAPS is available from any PC. All the technical documentation and information you need to service your pumps is immediately available to you, at any time:
- Service instructions
- Step-by-step service videos
- Interactive exploded views
- Sectional drawings.
A service video is available for this product. The service video is an easy way to see how to disassemble and assemble the pump.
The WebCAPS literature and service sections offer quick and easy access to service videos.
There are two different ways to access the videos from the WebCAPS home page:
- via Service
- via Literature.
The videos are also available on CD-ROM and DVD.
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Select country to contact your local service center