Air driven liquid pumps Ideal for hydrostatic testing with water or oil
- Air-driven hydraulic pumps up to 80,000 psi (5,516 bar)
- Official HII distributors, warranty up to 12 months
- Air-driven: no electrical connection and no lubricated air
- Price and availability within 24 hours
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Price and availability within 24 hours
Tell us the liquid, pressure and flow rate, or the HII model code: a technician will reply within 24 working hours.
High pressure
Applications
- Hydrostatic testing at high pressure of tubing, ducts, valves, cylinders, tanks
- Leak testing of components
- High pressure flushing unit
- Control panels/wellhead emergency shutdown
- Control/action of valve actuators
- Discover all applications ›
HII liquid pumps: models, ratios and pressures
Interfluid distributes HII (Hydraulics International) air-driven hydraulic pumps. They work on the differential-area principle: an air piston drives a smaller-diameter piston or plunger. Outlet pressure is the drive air pressure (12–150 psi, 0.8–10 bar) multiplied by the pump ratio; once equilibrium is reached the pump stalls and holds pressure without consuming energy. Data from the HII catalogue.
3L series: 3 inch air piston, single acting
| Model | Max pressure psi (bar) | Displacement per cycle (cm³) |
|---|---|---|
| 3L-SS-8 | 1,200 (83) | 13.4 |
| 3L-SS-14 | 1,950 (134) | 7.5 |
| 3L-SS-25 | 3,750 (259) | 4.1 |
| 3L-SS-41 | 6,150 (424) | 2.5 |
| 3L-SS-81 | 12,150 (838) | 1.3 |
| 3L-SS-125 | 15,000* (1,034) | 0.8 |
| 3L-SS-220 | 15,000* (1,034) | 0.5 |
* Continuous-duty limit for stainless steel versions. In intermittent service: 18,750 psi (1,293 bar) for 3L-SS-125 and 21,000 psi (1,448 bar) for 3L-SS-220.
5L series: 5-3/4 inch air piston, single acting, single drive (SS)
| Model | Max pressure psi (bar) | Displacement per cycle (cm³) |
|---|---|---|
| 5L-SS-10 | 1,500 (103) | 72.4 |
| 5L-SS-15 | 2,250 (155) | 50.3 |
| 5L-SS-30 | 4,500 (310) | 30.8 |
| 5L-SS-45 | 6,750 (465) | 20.3 |
| 5L-SS-60 | 9,000 (621) | 14.6 |
| 5L-SS-115 | 17,250 (1,189) | 7.9 |
| 5L-SS-150 | 22,500 (1,551) | 5.9 |
| 5L-SS-205 | 30,750 (2,120) | 4.3 |
| 5L-SS-300 | 45,000 (3,103) | 2.9 |
| 5L-SS-450 | 67,500 (4,654) | 1.9 |
5L series: single acting, double drive (SD) and triple drive (ST)
| Model | Max pressure psi (bar) | Displacement per cycle (cm³) |
|---|---|---|
| 5L-SD-20 | 3,000 (207) | 72.4 |
| 5L-SD-30 | 4,500 (310) | 50.3 |
| 5L-SD-60 | 9,000 (621) | 30.8 |
| 5L-SD-90 | 13,500 (931) | 20.3 |
| 5L-SD-120 | 18,000 (1,241) | 14.6 |
| 5L-SD-230 | 34,500 (2,379) | 7.9 |
| 5L-SD-300 | 45,000 (3,103) | 5.9 |
| 5L-SD-410 | 61,500 (4,240) | 4.3 |
| 5L-SD-600 | 80,000 (5,516) | 2.9 |
| 5L-ST-900 | 80,000 (5,516) | 2.9 |
5L series: double acting (DS, DD)
| Model | Max pressure psi (bar) | Displacement per cycle (cm³) |
|---|---|---|
| 5L-DS-4 | 1,250 (86) | 394.9 |
| 5L-DD-20 | 3,000 (207) | 144.9 |
| 5L-DD-30 | 4,500 (310) | 100.6 |
| 5L-DD-60 | 9,000 (621) | 61.6 |
| 5L-DD-90 | 13,500 (931) | 40.6 |
| 5L-DD-120 | 18,000 (1,241) | 29.2 |
| 5L-DD-230 | 34,500 (2,379) | 15.7 |
| 5L-DD-300 | 45,000 (3,103) | 11.8 |
| 5L-DD-410 | 61,500 (4,240) | 8.5 |
| 5L-DD-600 | 80,000 (5,516) | 5.9 |
Models 5L-DS-4, 5L-DD and 7L-DS-7 use the inlet liquid pressure to increase force (catalogue example: 200 psi inlet and 100 psi air give about 600 psi stall) and draw in and deliver half the displacement on each stroke. Models 7L-DS-35 … 7L-DD-200 draw in the full displacement and deliver half of it per stroke. For 5L-SS-450, 5L-SD-600 and 5L-ST-900 in heavy-duty hydrostatic testing the catalogue recommends a booster pump, for example the 3L-SS-41.
7L series: 7 inch air piston, double acting (DS, DD)
| Model | Max pressure psi (bar) | Displacement per cycle (cm³) |
|---|---|---|
| 7L-DS-7 | 1,250 (86) | 678.4 |
| 7L-DS-35 | 5,250 (362) | 127.8 |
| 7L-DS-60 | 9,000 (621) | 77.0 |
| 7L-DS-100 | 15,000 (1,034) | 45.9 |
| 7L-DD-70 | 10,500 (724) | 127.8 |
| 7L-DD-120 | 18,000 (1,241) | 77.0 |
| 7L-DD-200 | 20,000* (1,379) | 45.9 |
* Continuous-duty limit for stainless steel versions; in intermittent service 20,000 psi (1,379 bar). How to read the code, for example 5L-SD-300-X: series (3L, 5L, 7L), acting (S single, D double), air pistons (S single, D double, T triple), nominal ratio and modification. The actual ratio is about 15% higher than nominal. Max pressure refers to 10 bar (150 psi) drive air.
Liquids, materials and temperatures
- Fluids: hydraulic oils (mineral, vegetable), plain, distilled and deionised water, solvents compatible with Buna-N, Skydrol and brake fluids with modifications D and E.
- Liquefied gases: 3L and 5L series; not the 7L series, except model 7L-DS-7.
- Wetted parts in stainless steel (316 and 15-5 PH depending on the model), aluminium on -4 and -7 models; dynamic seals in UHMWPE, static seals in Buna-N.
- Temperature: +10 to +150 °F (−12 to +66 °C); with modification V the air section up to about 200 °F (93 °C); liquid section max 180 °F (82 °C).
Standard modifications
| Code | Function |
|---|---|
| B | Bottom inlet: modification for 5L-SS-30…-450 and 5L-SD-60…-600; standard on 3L, 5L-SS-10/-15, 5L-SD-20/-30 and 5L-DD-30…-300 |
| D / DD | Spacer (double spacer on 5L series only): double vented seal that protects the air section from liquid leaks or vapours |
| E | EPR static seals in the liquid section, for liquids incompatible with Buna (Skydrol) |
| H | Hand pump connection, 3L series only |
| L | Low drive air pressure (2–3 psi), 5L series only; requires external pilot ≥ 30 psi |
| P | Ducted exhaust: allows submerged operation in tanks or venting gases outside the area |
| S / RC | Single stroke (S) or return command (RC): for testing, dosing and precise control of the test pressure |
| V / V1 | Viton seals in the air section (V) or static in the liquid section (V1): higher temperatures and chemical resistance |
| X | External pilot port to start and stop the pump with a small valve |
| R / T | Return spring removed (3L) or 3-way spool (5L), for pressurised suction such as with liquefied gases |
HII high pressure accessories and components
| Component | Models | Pressure / range | Notes |
|---|---|---|---|
| Liquid relief valves | RVL-100 | setting 1,000–10,000 psi (69–689 bar) | Stainless steel; low flow; Viton (V) or EPR (E) options |
| High pressure relief valves | RV-300, RV-600 | 3,000–30,000 psi (207–2,069 bar); 10,000–60,000 psi (689–4,137 bar) | For liquids or gases; also usable as sequence valves or back-pressure regulators |
| Pilot stop valves | PCV | ranges from 50–200 to 5,000–25,000 psi (up to 26,000 psi) | Sense liquid or gas pressure and give or remove the air signal to start and stop pumps and valves; max air 120 psi |
| Unloading valves | UV-50, UV-80, UV-120, UV-200 | 5,000, 8,000, 12,000 and 20,000 psi (345, 552, 827, 1,379 bar) | Normally closed, opened by air pilot; UV-150-2 two-stage, inlet up to 15,000 psi |
| Pneumatic on/off valve | AOV-100 | 10,000 psi (689 bar) | Normally open, leak-tight; 316 stainless steel, Cv 0.75, pilot 30–150 psi, 1/4 inch NPT ports |
| Check valves | CVH-025, CVH-050, CVM-200 | liquid: 15,000, 20,000 and 5,000 psi (1,034, 1,379 and 345 bar) | 316 stainless steel body; 1/4, 1/2 and 2 inch NPT ports |
| Intensifier | IA100K3 | outlet up to 100,000 psi (6,895 bar) | Displacement about 3 in³ (49 cm³) per cycle; min inlet 1,500 psi with liquid; max 2 cycles/min |
HII power units
HII power units are ready to use: you only need compressed air and the connection to the item under test. The standard HIHPT4 version includes air controls (regulator, filter, gauge and speed control valve), air-driven pump, stainless steel tank with level indicator and filler cap, high pressure gauge, outlet shut-off valve and tank return valve. On request: relief valves, pilot stop valve, chart recorders, high pressure hoses, flowmeters and filters. For complete test units see the testing units with liquids.
Why choose them
- No electrical connection, no lubricated air
- Pressure held without energy consumption and without heating the fluid
- Self-priming and tolerant of contamination
- Stall pressure set by the drive air regulator
- Ideal for start-stop cycles under full load
- Compact, lightweight and weather proof
- Can also be driven with nitrogen, line gas and liquefied-gas vapour, with suitable modifications
Catalogue applications
- Hydrostatic testing and calibration of pressure components
- Clamping and pressing: cylinders that hold force for a long time without generating heat
- Valve actuator operation with line gas
- Portable hydraulic tools and compact power units with tank
- Industries: manufacturing, mining, automotive, machine tools, energy, oil & gas, defence, research and laboratories
Frequently asked questions
What pressure do HII pumps reach?
Up to 80,000 psi (5,516 bar) with models 5L-SD-600, 5L-ST-900 and 5L-DD-600. Outlet pressure is the drive air pressure (12-150 psi, 0.8-10 bar) multiplied by the pump ratio.
Which series should I choose: 3L, 5L or 7L?
The 3L series (3 inch air piston) is the most compact, up to 15,000 psi (1,034 bar) continuous. The 5L (5-3/4 inch) covers 1,250 to 80,000 psi (86 to 5,516 bar). The 7L (7 inch) gives more flow at medium pressures, up to 20,000 psi (1,379 bar).
Do they need lubricated air or electric power?
No: HII pumps need neither lubricated air nor electrical connections. They can also be driven with nitrogen and other gases, with suitable modifications.
Which liquids can they be used with?
Hydraulic oils, plain, distilled and deionised water, solvents compatible with Buna-N. Skydrol and brake fluids require modifications D and E. Temperature from −12 to +66 °C (+10 to +150 °F).
How soon do I get price and availability?
A technician will reply within 24 working hours. Tell us the liquid, maximum pressure, flow rate and available air pressure.
See also: testing units with liquids, HII air-driven gas boosters, HII electric gas boosters and HII air amplifiers.
Can't find the model code you need?Tell us the liquid, maximum pressure, flow rate and available air: a technician will reply within 24 working hours.
Request price and availabilityAir driven liquid pumps description
Air driven liquid pumps convert compressed air into hydraulic pressure (up to 80,000 psi). No electrical connection or lubrication is required.
Hydraulic outlet pressure is equal to the drive air pressure multiplied by the pump pressure ratio. Once the high pressure air-driven pump reaches the pre-set pressure it will automatically stall and maintain the pressure. In case of a pressure drop downstream, the pump will automatically restart.
High performance air-driven pumps provide a highly safe, reliable and long-lasting hydraulic power source for applications up to 68,000 psi (4,688 bar).
These pumps are built to run at their maximum rated pressure and feature a robust motor and seal design that delivers a long lifetime. Moreover, they do not require a lubricated air source and incorporate several features to facilitate easy installation and service.
These pumps reach a “bubble tight” pressure stall that can be used for high pressure applications such as: valve actuation, hydraulic power units, bolt tensioning, jacking, lifting, power pressing, pressure testing and proof testing of components, work holding and clamping, hydraulic cylinder actuation, chromatography, lubrication and spraying, liquefied gas transfer.
Combining HiP’s high pressure expertise with Graco’s extensive pump engineering background, T-Series pumps address many of the shortcomings typically found in air driven pumps.
T-Series is available with the Graco DataTrak electronic monitoring system, equipped with:
- Stroke counter
- Cycle rate display
- Runaway protection
Features
- Maximum working pressure: 80.000 psi (5500 bar)
- Compatible with all hydraulic fluids
- Stainless steel body and check valves in contact with liquid
- Drive air lubrication is not required
- Operate with compressed drive air (gas) from 116 psi (0.8 bar) to 145 psi (10 bar)
- Possible to drive with other inert gases
- Feed from mains or from a tank
Benefits
- Wide range of special modifications available
- Compact, lightweight, robust and weather proof
- Easy to incorporate and operate
- Ideal for START/STOP applications under load
Applications
- Hydrostatic testing at high pressure of tubing, ducts, valves, cylinders, tanks
- Leak testing of components
- High pressure flushing unit
- Control panels/wellhead emergency shutdown
- Control/action of valve actuators
- Power unit for tensioning – torque tools
- Packers inflation
- Press overload circuit
- Blocking cylinder actuation
- Burst test benches
Alternative to:
- Haskel
- Maximator
Download
- HII air driven liquid pumps catalogueDownload HII air driven liquid pumps catalogue
- Sprague air driven liquid pumps catalogueDownload Sprague air driven liquid pumps catalogue
- HIP air driven liquid pumps catalogueDownload HIP air driven liquid pumps catalogue
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High pressure • 17 Ocotber, 2023
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