1. Start with your application

According to the product description, the double acting power units consist of a high pressure gear pump, a motor, a multifunctional manifold, valves and a tank. The supplier describes them as having stable performance and a compact structure, and lists automotive, garden machinery, machine tools and logistics equipment as typical fields of use.

The published model description also states that the unit:

• uses a double-action solenoid valve, which switches flow direction (the source wording is "turn over through the solenoid valve");
• uses an assembled gear pump;
• has an oil suction filter screen.

If your cylinder needs to be driven in both directions through a solenoid valve, this configuration is the one to examine. The confirmed material does not cover single acting power units, so this article does not compare the two designs. Ask the supplier for separate documentation if you are considering a single acting unit.

2. Match the electrical supply

The specification table lists motor voltage options of 12V, 24V, 220V and 380V. Low-voltage options are normally relevant to vehicle-mounted or battery-powered equipment, while 220V and 380V entries are relevant to equipment connected to mains power.

There is one point to confirm. The model description says the product "uses a DC motor," but the table also contains 220V and 380V entries. Before ordering, ask the supplier to confirm the motor type (AC or DC), phase and frequency for the exact model. This matters most if you buy for more than one market, such as the US, Europe, the Middle East or Southeast Asia, because local supply standards differ.

3. Check motor power, displacement and relief pressure together

The published table includes these ranges:

These values cannot be mixed freely. In the table, displacement and relief pressure come paired. For example, the 2.1 ml/r entry is listed at 20 MPa, while the 4.2 ml/r entry is listed at 10 MPa. A configuration with more flow per revolution may therefore have a lower listed relief setting. Choose the row that meets both your cylinder speed requirement (flow) and your force requirement (pressure).

The published table merges some voltage and power cells. Ask the supplier for a model-by-model sheet that shows voltage, motor power, displacement, relief pressure, tank capacity and length on one line for each model. Also confirm the units of the larger tank entries (16, 20, 22 and 25), which are listed without units.

4. Size the tank and check the installation space

The model description mentions a five-liter tank, while the table lists capacities from 3 L upward. Decide on tank size based on your cylinder volume and duty, then confirm the exact capacity for the model you choose.

The listed overall length (L) runs from 472 mm to 1100 mm depending on configuration. Check this against the available space. The unit must be mounted horizontally, so the length has to fit in a horizontal position.

5. Respect the duty cycle

The supplier rates this power unit at S3 duty: 30 seconds on and 270 seconds off. This is a key limit. If your machine needs continuous or near-continuous pumping, this unit as published does not apply, and you should discuss other options with the manufacturer rather than assume the unit will cope.

6. Plan oil and maintenance

The published notes specify:

1. Clean all related hydraulic parts before mounting the power unit.
2. Use hydraulic oil with a viscosity of 15 to 68 cSt. The oil must be clean and free of impurities. N46 hydraulic oil is recommended.
3. Change the oil after the first 100 hours of operation, then every 3000 hours.
4. Mount the power unit horizontally.

Include these requirements in your equipment manual or service plan so end users follow them.

When a different unit may fit better

If your application is lifting and left-right swing of a snowplow blade on a truck, the same supplier publishes a separate snowplow power unit. It is designed specifically for that job, offers different circuits and valves as options, and can include manual emergency oil release if specified when ordering. Its published table lists 12V and 24V options with 1.2 to 2.7 ml/r displacement. It carries the same S3 duty, oil and horizontal mounting requirements.

Buyer checklist

• Does your circuit need double-action solenoid switching?
• Which voltage, and is the motor AC or DC for that row?
• Which displacement and relief pressure pair meets your speed and force needs?
• What tank capacity and overall length fit your machine with horizontal mounting?
• Can your duty cycle stay within S3 (30 s on / 270 s off)?
• Can you supply clean 15 to 68 cSt oil (N46 recommended) and follow the oil change intervals?
• Have you confirmed price, lead time and any required certifications in writing?

Hebei Shenghan Hydraulic Machinery Co. , Ltd. mainly produces hydraulic cylinders and power units. Send your application details with your enquiry so the supplier can confirm the right configuration.