Air Over Oil Intensifier FAQ: Converting Shop Air to Hydraulic Power

Model Selection & Configuration

An air over oil intensifier converts shop air into hydraulic pressure to provide an in-line power boost when a specific task requires more force than compressed air can deliver. This is an ideal solution for environments where compressed air is the only available power source: 

• Simple, reliable, stable additional force when and where needed
• Streamlined installation
• Cost-efficient
• No need to install or maintain tanks or other hydraulic equipment
• May reduce the need for additional pneumatic caliper brakes to achieve desired braking

Discover the benefits of air over oil intensifiers

What models are available?

We offer six standard-rod intensifier models with pressure change ratios ranging from 5:1 to 36:1, plus our OVLBOOST intensifier that has an oval rod. Displacement is based on bore size and stroke length.

• INT05: 5:1 ratio, for use with hydraulic caliper disc brakes or other hydraulic applications

• INT09: 9:1 ratio, for use with hydraulic caliper disc brakes or hydraulic spring applied brake

• INT10: 10:1 ratio, for use with hydraulic caliper disc brakes and other hydraulic applications
• INT18: 18:1 ratio, for use with hydraulic caliper or hydraulic spring applied brakes
• INT20: 20:1 ratio, for use with hydraulic caliper disc brakes and other hydraulic applications

• INT36: 36:1 ratio, for use with hydraulic caliper disc brakes and other hydraulic applications 

• OVLBOOSTTM: 7.8:1 ratio (44 mm) or 7:1 ratio (25mm), for use with our Branham brakes and also to operate small hydraulic cylinders

See our entire lineup of air over oil intensifiers

How do they work?

An air over oil intensifier is a compact, self-contained device with two chambers. Compressed air retracts a piston in the first chamber, which pressurizes hydraulic fluid or oil in the second chamber, enabling the second piston to produce the required force. 

The area of the two piston surfaces determines the ratio of pressure change. For example, in a 10:1 intensifier, the surface of the pneumatic piston will be ten times greater than the surface of the hydraulic piston. Pressure increase is conversely related to fluid pressure.

Increase hydraulic pressure using shop air

How is OVLBOOST different?

This model uses the same functional concept as our other air over oil intensifiers. However, its shorter but wider shape provides a more compact option to save space. OVLBOOST is derived from Branham’s OVLPRO rodded pneumatic cylinder which also features an oval shape, but in this case the device is designed to convert air to hydraulic pressure.

Discover the benefits of OVLBOOST

How do I choose the correct size?

Output volume depends on fluid volume and pressure change ratio. If space is limited, OVLBOOST may be the best option.

Your sizing questions, answered

How much air volume is needed to cycle the intensifier? 

Multiply the hydraulic fluid displacement by the ratio. For example, a 10:1 intensifier will displace .44 cubic inches of fluid per stroke, so the amount of air would be ten times that, or 4.4 cubic inches.

Can it be used as a closed-loop system?

Yes. Once the system is filled and bled of all air it can be used as a closed-loop system. In this case the reservoir no longer needs to be attached to the intensifier. The supplied check valve should remain. It is not necessary to remove the reservoir, however. 

How is it oriented?

Once established in a closed-loop system, the intensifier can be mounted in any direction. Mounting holes allow the air over oil intensifier to be mounted directly to the platform or the application. Note that, if you’re using a reservoir kit, the intensifier must be attached so that the reservoir is vertical to allow the fluid to feed into the intensifier via gravity.

Can air over oil intensifiers be used with spring-applied brakes?

Yes. Air over oil intensifiers can be used with any Branham brake, as long as fluid displacement and resulting hydraulic pressure matches what is required to operate the brake.

Can I use more than one intensifier to increase pressure?

Yes. Air over oil intensifiers can be used together in parallel, but they cannot be used in series to increase pressure. For parallel application, air hoses are attached to both intensifiers so that a single pneumatic stroke can achieve the greater desired hydraulic pressure without exponentially increasing the volume.

Can they be used with brake fluid?

Yes, DOT-3 or DOT-4 fluid can be used instead of standard mineral oil-based fluid. In this case be sure to specify the ‘G’ denominator which is EPR instead of Buna seals.

Can an air over intensifier be used with other hydraulic components?

Yes, as long as the fluid capacity required is within the intensifier’s ratings.

Can air over oil intensifiers be customized?

Yes, customized design is possible for higher-volume orders. That might include a simple change to mounting configuration, or if greater output volume is required, a longer stroke length can be used to accommodate that.

Talk to an expert about your custom design needs

How much lead time is required?

Standard lead time for components that are in stock is 1-week to ship.

Performance & Operating Conditions

We offer air over oil intensifiers for every Branham hydraulic and spring-applied hydraulic caliper brake.

INT05

• 5:1 ratio
• .44 cubic inch displacement per stroke
• Maximum input 100 psi
• Maximum output 500 psi
• Spring retract

INT09

• 9:1 ratio
• 7.068 cubic inch displacement per stroke
• Maximum input 100 psi
• Maximum output 900 psi
• Double-Acting

INT10

• 10:1 ratio
• .44 cubic inch displacement per stroke
• Maximum input 100 psi
• Maximum output 1000 psi
• Spring retract

INT18

• 18:1 ratio
• 7.068 cubic inch displacement per stroke
• Maximum input 100 psi
• Maximum output 1800 psi
• Double-acting

INT20

• 20:1 ratio
• .50 cubic inch displacement per stroke
• Maximum input 100 psi
• Maximum output 2000 psi
• Spring retract

INT36

• 36:1 ratio
• 1.77 cubic inch displacement per stroke
• Maximum input 100 psi
• Maximum output 3600 psi
• Spring retract

OVLBOOST 44mm

• 7.8:1 ratio
• 1.50” stroke with .460 cubic inch displacement or 3.00” stroke with .920 displacement
• Single side or rear porting
• Maximum input 100 psi
• Double-acting

OVLBOOST 25mm

• 7:1 ratio
• 2.00” inch stroke with 0.22 cubic inch displacement
• Maximum input 100 psi
• Double acting

What operating conditions do intensifiers support?

• Pressure Range: 20 to 100 psi
• Operating Temperature: -20o to 200o F
• Media: Compressed and filtered air, dry or lubricated

Can intensifiers be used with outdoor applications?

All of our intensifiers feature anodized aluminum housing, either clear or black. They can be exposed to outdoor elements – in fact some customers use them on off-road vehicles. 

For outdoor use, we build the intensifiers with stainless steel fasteners, rods, and other key components to protect against corrosion. The housing and tubing are not stainless steel. We recommend you work with our sales team to determine whether an air over oil intensifier is appropriate for your specific application.

Can intensifiers be used in high-temperature environments?

These products are not suitable in cases where VITON seals would be required.

Can I use an intensifier at low air pressures?

In order to activate the piston and ensure proper performance, our air over oil intensifiers are designed to operate at 20-25 psi or higher.

Application Suitability

What applications are best suited for air over oil intensifiers?

Air over oil intensifiers are extremely versatile, offering a wide range of conversion ratios. They can provide an in-line, on-demand hydraulic power boost in systems that otherwise use compressed air for:

• Tensioning
• Stop-and-hold
• Emergency braking

Intensifiers are also ideal for small hydraulic devices that do not require high-volume fluid displacement. That makes them a great choice for a wide range of real-world applications beyond braking:

1. Web, wire, or coil winding machines
2. Wind turbines
3. Agricultural equipment
4. Robotics
5. Mining
6. Amusement park rides
7. Grippers
8. Indexing tables
9. Vices
10. Welding positioning equipment
11. Railroad cars

Read how customers are using intensifiers

Can air over oil intensifiers handle harsh environments?

Anodized aluminum housing enables our air over oil intensifiers to withstand humid or wet conditions. They are suitable for heavy washdown and outdoor environments where dirt, debris, or harsh chemicals may be present.

Maintenance & Serviceability

How much maintenance do air over oil intensifiers require?

These devices are low-maintenance. They can be disassembled for repair and reassembled onsite.

• Do not exceed the rated maximum pressure of the brake, as this can cause failure.
• Air within the hydraulic circuit diminishes compression, so it is important to fully bleed the air to ensure proper ratio and performance.
• Replace seals if air or hydraulic fluid leaks are detected.

Download the maintenance guide for models 1777, 1778, 1779, and 1782

Download the maintenance guide for models 1780 and 1781

Why should I choose a Branham air over oil intensifier for my application?

• Manufacturing quality: Our intensifiers are manufactured in Wisconsin by W.C. Branham using the highest quality materials and workmanship.
• Convenience and savings: Intensifiers offer a simple, cost-efficient solution where extra force is required for specific tasks but only compressed air is available.
• Versatility: Air over oil intensifiers are convenient and highly versatile, ideal for indoor and outdoor applications.
• Seal variety: Both standard and high-temperature seals are available.
• Short lead time: Standard lead time of one week to ship.
• Responsive technical support: Application assistance and troubleshooting from Branham engineers familiar with North American industrial applications, without extensive time-zone delays.
• North American distribution: Responsive delivery from Branham’s central-USA location minimizes time from order to receipt. 

Ordering & Support

How do I order an air over oil intensifier or get support?

Contact W.C. Branham to discuss your application requirements.

• Phone: 1-800-428-1974 (U.S./Canada) or 715-426-2000 (local)
• Email: AskWCB@wcbranham.com
• Website: www.wcbranham.com