Customers often ask, “when do I need a two-stage hand pump versus a single-stage hand pump?” Well, that depends on the type of work you are trying to do inside your hydraulic system. There is a measurable difference between the two of them and both have benefits depending on the application. To explain, let’s look at the new PowerX International line of hand pumps.
First up is the PowerX P43 single-stage 10,000 psi (700 bar) hand pump. The reason why it is called a “single-stage” pump is because the flow of oil produced is the same on each stroke of the handle. For the PowerX P43, the flow is a continuous 0.20 in3 of oil per stroke. The pumps flow rate remains constant, whether it is simply raising a single acting cylinder with no weight on it, or pushing 10 tons at 10,000 psi. A single-stage pump is great if your hydraulic ram does not have to travel far before it starts to lift or push the load. But if the ram needs to travel any significant distance to meet the load, there would be a lot of excessive pumping by the operator before they actually started to do any work. This would get tiresome very quickly!
Enter the PowerX P37 “two-stage” 10,000 psi (700 bar) hand pump. Two stage hydraulic hand pumps give the operator higher flow rates up until the cylinder or ram starts to do work. In the case of the PowerX P37 hand pump, the first stage has a flow of 0.79 inches3 of oil per stroke (almost 4 times more than the P43) before making contact with the work load where the pressure builds. Once the ram makes contact with the load, and the pressure inside the system raises above 200 psi, the second stage kicks in at 0.17 in3 of oil volume. This two-stage pump allows the operator to do less work (or hand pumping) before coming into contact with the load. Your operators will thank you!
Both the PowerX P43 and the PowerX P37 are built with rugged steel construction and both have internal pressure relief valves to protect against overload. To learn more about the PowerX line of 10,000 psi (700 bar) hand pumps, click here.