DHP 11 Axial Piston Pumps(High Pressure Pump For Industrial Reverse Osmosis)
The DHP 11 Axial Piston Pump is a High Pressure Pump For Industrial Reverse Osmosis developed by Wuxi Fenigal Science and Technology (FENIGAL) in collaboration with its OEM partner Shenzhen CW Environment Technology. It is specifically designed for conveying high-pressure, low-viscosity corrosive fluids in industrial reverse osmosis systems, such as high-salinity wastewater concentration, seawater/brackish water desalination, and landfill leachate treatment. Based on the axial piston principle, the pump operates by the reciprocating motion of plungers parallel to the drive shaft within plunger bores, creating volume changes to achieve fluid transfer. It adopts fluid self-lubrication technology (eliminating the need for a lubricating oil tank) to avoid oil leakage pollution. Additionally, it integrates a check valve, which ensures one-way fluid flow from the inlet to the outlet when the pump is stopped, enhancing system safety.
As a key model in the DHP series, the DHP 11 inherits the core advantages of the series: "high efficiency, corrosion resistance, and low noise". Its components are made of corrosion-resistant materials such as 2205 duplex stainless steel (SAF 2205 / EN 1.4462 / UNS 31803), providing excellent resistance to salt spray and corrosion from high-concentration NaCl media. During operation, the pump generates significantly less pulsation than other pump types, resulting in low vibration and noise. With a compact structure, it can be directly installed on a motor or internal combustion engine, making it suitable for industrial sites with sensitive space requirements.
In terms of application scenarios, the DHP 11, as a High Pressure Pump For Industrial Reverse Osmosis, is widely used in three core fields: (1) Desalination of seawater and brackish water in islands and coastal areas; (2) Industrial wastewater desalination, resource recovery, and salt concentration for zero liquid discharge; (3) Reverse osmosis treatment of refractory wastewater such as desulfurization wastewater from coal-fired power plants and coking wastewater from coal mines. This aligns with FENIGAL's technical positioning since it began developing high-pressure plunger pumps in 1990: "addressing bottlenecks in related products and promoting the localization of axial high-pressure plunger pumps". Its technical level and product quality have reached world-class standards, capable of meeting the stable high-pressure fluid transfer needs of industrial reverse osmosis systems.
The technical parameters of the DHP 11 high-pressure plunger pump cover key indicators such as geometric displacement, flow rate, pressure, speed, power, and temperature adaptability, which are crucial for model selection and system matching. The specific parameters are shown in the table below:
| Technical Parameter Item | Value/Specification |
|---|
| Product Model | DHP 11 |
| Geometric Displacement | 133 cm³/rev |
| Flow Rate at Rated Speed (1500 rpm) | 11 m³/h |
| Minimum Outlet Pressure | 10 Bar |
| Maximum Continuous Outlet Pressure | 80 Bar (Contact the manufacturer for higher/lower pressure if needed) |
| Minimum Inlet Pressure | 2 Bar |
| Maximum Continuous Inlet Pressure | 5 Bar |
| Maximum Continuous Speed | 1500 rpm |
| Minimum Continuous Speed | 700 rpm |
| Noise Level (per EN ISO 3744-2010) | ≤85 dB(A) (Measured at maximum pressure and speed of the entire pump unit) |
| Power at 1500 rpm and 80 Bar | 30 kW |
| Medium Temperature | 2～50℃ (Depends on NaCl concentration) |
| Ambient Temperature | 0～50℃ |
| Equipment Weight | 52 kg |
| Integrated Function | Flush Check Valve (Available) |
As a fixed-displacement axial piston pump, the flow rate of the DHP 11 is proportional to the input shaft speed (the flow rate/speed ratio is fixed). The required flow rate can be achieved by adjusting the speed. If the flow rate required by the system is known, the corresponding motor speed can be calculated using the following formula:
Selected Motor Speed (r/min) = (Required Flow Rate (m³/h) × Rated Speed (r/min)) / Rated Flow Rate (m³/h)
The figure below shows the flow rate - speed curve of the DHP 11 at 80 Bar pressure, which allows for intuitive viewing of the actual flow rate corresponding to different speeds (e.g., approximately 5 m³/h at 700 rpm and the rated 11 m³/h at 1500 rpm), providing a reference for system speed matching:
As a High Pressure Pump For Industrial Reverse Osmosis, the DHP 11 must be installed and operated in strict accordance with specifications to ensure stable system operation and extend the pump's service life. The core points are as follows:
Filtration Requirements: Since industrial reverse osmosis media (such as high-salinity wastewater) may contain tiny particles, a 10 μm (absolute accuracy) depth filter must be installed at the inlet of the DHP 11. It is required to have a filtration efficiency of 99.98% for particles larger than 10 μm (β10>5000) to avoid particle wear on the precision clearances inside the pump (spiral-wound filter elements are recommended; bag filters with only 90% efficiency are not recommended).
Pressure Control: A low-pressure control switch (set to 1 Bar) must be installed at the inlet to automatically shut down the pump when the pressure is lower than 1 Bar, preventing cavitation. A high-pressure control switch (set to 70 Bar) must be installed between the outlet and the reverse osmosis membrane to shut down the pump when the pressure exceeds the limit. Additionally, a safety valve must be installed to prevent instantaneous pressure damage to the system after the pump starts.
Pre-Startup Preparation: Before startup, thoroughly flush the pipelines and system to remove debris; discharge air from the pump and system to prevent cavitation; confirm that the pump rotation direction is consistent with the arrow on the pump body. Starting the pump with the outlet valve closed is prohibited (as it may cause the safety valve to operate or the pipeline to burst).
The figure below shows the standard connection method between the DHP series high-pressure pump and the motor. When installing the DHP 11, ensure that the coupling clearance is at least 3 - 5 mm and that there is no axial/radial load on the pump shaft:
The power consumption of the DHP 11 varies with operating pressure. The power values at different typical pressures are shown in the table below, which can be used for system motor selection (e.g., matching a 30 kW motor can meet the rated operation requirements at 80 Bar):
| Pump Model | Rated Flow Rate (L/min) | Rated Flow Rate (m³/h) | Power at 60 Bar | Power at 70 Bar | Power at 80 Bar | Rated Speed (rpm) |
|---|
| DHP 11 | 183 | 11 | 22 kW | 30 kW | 30 kW | 1500 |
The outline dimensions of the DHP 11 (especially the inlet/outlet interface dimensions) and the installation dimensions of the complete equipment (including the frequency conversion motor) are crucial for pipeline connection and on-site layout. The details are as follows:
Interface Dimensions: Both the inlet and outlet of the DHP 11 feature M52×1.5 threads with a depth of 17 mm, requiring matching high-pressure pipe fittings of the corresponding specification.
Complete Equipment Dimensions: When the DHP 11 is equipped with an independent fan motor (frequency conversion motor), the installation dimensions corresponding to motors of different powers are shown in the table below (Unit: mm):
| Pump Model | A | B | H | K | P | AD | HD | C | D | L | G | IEC Motor |
|---|
| DHP 11 | 279 | 279 | 180 | 15 | 350 | 265 | 445 | 275 | 204 | 735 | 1214 | 22 kW -4P |
| DHP 11 | 318 | 305 | 200 | 19 | 400 | 305 | 505 | 275 | 204 | 765 | 1244 | 30 kW -4P |
| DHP 11 | 356 | 286 | 225 | 19 | 450 | 325 | 550 | 275 | 234 | 760 | 1269 | 37 kW -4P |
| DHP 11 | 356 | 311 | 225 | 19 | 450 | 325 | 550 | 275 | 234 | 785 | 1294 | 45 kW -4P |
The figure below shows the outline structure diagram of the DHP 11, marking key information such as the inlet/outlet positions and installation interfaces:
Although the DHP 11 adopts a self-lubricating design (no lubricating oil required), proper maintenance can significantly extend its service life. The core maintenance points are as follows:
Daily Maintenance: If abnormal noise or vibration occurs during operation, stop the pump immediately for inspection and repair. In high-salinity environments (such as seawater desalination), flush the pump cavity with fresh water after each shutdown to discharge concentrated brine and prevent crystallization from damaging the seals and plungers.
Shutdown Maintenance: For short-term shutdowns (≤3 days), no flushing is required; simply keep the pump filled with the medium. For medium-term shutdowns (3～15 days), flush the pump with fresh water. For long-term shutdowns (>15 days), flush the pump with fresh water containing a bactericide to prevent microbial growth.
Regular Inspection: A comprehensive inspection is recommended after 8,000 hours of operation, and worn parts (such as seal plates and plunger sleeves) must be replaced to avoid complete pump failure.
FENIGAL provides comprehensive warranty and maintenance services for the DHP 11, as shown in the table below:
| Service Type | Service Content | Remarks |
|---|
| Free Warranty | 1-year free maintenance from the date of ex-factory (excluding damage caused by human error or improper use); 8,000-hour maintenance-free warranty (not exceeding 18 months from the production date) | The 8,000-hour warranty is only applicable if the pump operates under "specified filtration, pressure, and speed conditions" |
| Fault Handling | Axial piston pump fault detection, on-site maintenance, and factory repair | Priority response upon receiving fault feedback to resolve issues quickly |
| Spare Parts and Customization Services | Provision of original spare parts (such as plungers and check valves); customization of special-specification parts according to customer needs | Spare parts are made of the same materials as the original to ensure compatibility |
| Maintenance for Similar Pumps | Provision of maintenance services for axial piston high-pressure pumps of other domestic and international brands | Adhering to the "customer-first" principle, covering maintenance needs for all types of axial piston pumps |
For maintenance or warranty inquiries, please contact Wuxi Fenigal Science and Technology: