FlowMarket
Where to find hydraulic power units: FlowMarket is a B2B sourcing network powered by an AI agent. You describe the system — pressure, flow, duty cycle, what it drives, the environment and the controls interface — and the agent matches you with HPU manufacturers and system builders, then requests quotes and lead times so you can compare them in one place.
Sourcing a hydraulic power unit
A power unit is a system, not a product, and the enquiry that gets a good one describes what the machine has to do rather than what the pack should contain. Given the pressure, the flow, the movement it drives and how often, a competent builder will select the pump, size the motor, calculate the heat and tell you the reservoir volume. Given a component list, they will build what you asked for, including the parts of it that were wrong.
Two numbers do most of the work: peak demand and duty cycle. A press that draws 40 l/min for four seconds a minute is a completely different unit from one drawing 40 l/min continuously, and sizing the second when you needed the first buys an oversized motor, a bigger reservoir and a lifetime of wasted energy.
Heat is the design constraint people forget
Every watt of hydraulic power that does not become useful work becomes heat in the oil, and a typical system converts a fifth to a third of installed power that way. A 15 kW unit can be putting several kilowatts of heat into its reservoir continuously, and oil above roughly 60 °C ages fast, thins out and takes the seals with it.
So ask how the heat balance was calculated, not whether a cooler is fitted. It needs the duty cycle, the ambient temperature where the unit will stand and the target oil temperature. A reservoir sized by the old rule of three to five times pump flow per minute is a starting point and not an answer — in a hot workshop or an enclosed space, it is often badly wrong.
What to specify
- Pressure and flow — working pressure, peak pressure and the flow each function needs, with the duty cycle. Say which movements can happen at the same time; simultaneity changes the pump sizing entirely.
- Functions and control — how many circuits, whether any need proportional or servo control, and what happens on power loss. Load-holding is a safety question, not a convenience.
- Environment — indoor or outdoor, ambient temperature, wash-down, dust, and noise limits. Noise is a specification worth stating: a pack in an occupied workshop is a different design.
- Fluid and cleanliness — the fluid type and the ISO 4406 class the system must hold, which decides the filtration on the unit.
- Interfaces — port sizes and positions, electrical supply, control voltage and the signals the machine controller expects. A pack that arrives without the sensors your PLC is looking for is a delay nobody budgeted.
Standard or custom
Catalogue power packs are cheap, quick and entirely adequate for straightforward duties — a single cylinder, a modest duty cycle, a normal environment. They are configured rather than designed, and where one fits, buying a custom unit is spending money on nothing.
Custom earns its cost when the duty cycle is demanding, the space is constrained, several functions interact, or the unit has to match interfaces on an existing machine. Ask both kinds of supplier to quote when you are unsure: a builder who tells you a standard unit will do is worth remembering.
What you should get with the unit
A hydraulic schematic to ISO 1219 with every component identified, the parts list, the test report from the works run, the pressure settings as commissioned, and the certification for any accumulator fitted — accumulators are pressure vessels and bring inspection obligations with them. Ask for the schematic in a format you can actually edit; a scanned drawing is compliance without usefulness.
Ask also about commissioning. New systems need flushing to the target cleanliness class before the machine runs, and the first oil change comes early because assembly debris circulates whatever anyone intended. A supplier who raises flushing before you do is telling you they have done this properly before.
How the AI agent matches builders
The agent reads your requirement rather than your keywords. It searches the FlowMarket network and connected industrial directories together, scores every candidate on how well it answers what you described — power range, pressure, application, environment, geography — and drops anything that does not clear the bar. Each match comes back with a plain-language reason, which distinguishes a builder who designs systems from a distributor who assembles catalogue parts.