Contributed by Hallie Riley & Victoria Lower • IC Fluid Power
When you step onto the floor of an industrial plant, the vast scale and constant hum of activity are undeniable. Massive hydraulic presses and intricate pipework stretch across the floor with the kind of freedom this scale allows. Space is abundant and equipment can be as robust and heavy as the job demands. It’s easy to take that freedom for granted until you’re working with a design where every inch counts.
Mobile applications face a different reality. Every valve, pump, and motor must be carefully chosen to keep the machine working hard without being weighed down by its own systems.
With every function competing for space, there’s little room for excess. That’s why engineers must rethink the components being used to maximize fuel efficiency, space, mass, cost, and more. Here are three areas where compact alternatives can make a big and efficient impact.
Rotating parts
Designing systems to rotate, lift, or steer loads in mobile equipment always raises the same question: how do you squeeze the most force and control into a compact package? Traditional configurations like rack-and-pinion actuators, cylinders, and levers can certainly get the job done, but often at the expense of valuable real estate.
Helical spline actuators help solve this problem. The internal mechanisms are straightforward. A helical splined shaft works in tandem with a sliding piston to convert linear movement into rotation. The splined teeth create a tight fit between components, resulting in a uniform and compact build.
For these reasons, helical spline actuators are noticeably shorter than some of the previously mentioned alternatives. Let’s consider an application that requires 360° of rotation with 3,540 lbf-in (400 Nm) of torque at 3,045 psi (210 bar). Using a rack-and-pinion actuator could require almost a foot and a half of installation space, while a helical actuator could deliver the same performance in just 4 in., taking up four times less space. Helical spline actuators have a larger profile in terms of height and width. That said, savings in linear space are often far more valuable in real-world applications where depth is the limiting factor in design.
Shutoff and regulating flow
Integrating emergency shutoff isn’t just best practice — it’s essential. Excavators and drill rigs often operate near sensitive waterways and ecosystems where even a small hydraulic leak could have serious environmental implications.
For years, ball valves have been the standard for flow regulation due to their affordability, easy actuation, and reliable sealing. Butterfly valves offer the same performance but differ mainly in cost and size. As designs become more sophisticated, saving space can be just as important as the cost.
Unlike ball valves which use a solid, heavy sphere, butterfly valves operate with a thin disk on a stem. The slim profile of the butterfly valve yields three main benefits: a smaller footprint, more design flexibility, and cost savings at larger sizes.
Butterfly valves are notably shorter and lighter than ball valves, especially as the pipe size increases. For a small 1.25 in. pipe, a typical ball valve is about 3.7 in. (95 mm) long, while a butterfly valve is about 1.4 in. (35 mm) making it roughly 60% shorter. On a 4 in. pipe, a butterfly valve can be as thin as 1.8 in. (45 mm) with a weight of 3.5 lb (1.6 kg). When compared to a 7.5 in. (190 mm) ball valve, the ball valve is almost four times heavier with a weight of 12 lb (5.5 kg).
The compact profile frees up valuable space, meaning system designs can include larger tanks or more flexibility when routing hoses and incorporating other parts into the system.
As the valve size increases, the cost advantage of butterfly valves becomes more pronounced. For example, on a 4 in. pipe, a ball valve can cost the same or even twice as much as a butterfly valve. Butterfly valves can be equipped with a proximity switch to ensure the hydraulic pump does not start if the butterfly valve is closed.
Intensifying pressure
When greater force output is needed, either the area or pressure must be increased. Since area is not always a viable option in mobile hydraulics, increasing system pressure becomes the most practical solution. This can be done in two ways.
One solution is upgrading to a pump with a higher pressure rating. This enables the system to maintain elevated pressure throughout all circuits, supporting continuous high-force operation.
Another option is using a pressure intensifier. This device is designed to boost pressure locally within a specific circuit or function, rather than throughout the entire system (though they are capable of doing so). This targeted approach allows you to achieve the necessary force exactly where it’s needed without the expense or space requirement of bulky equipment like high pressure pumps.
Many applications in construction and material handling could optimize space and efficiency with pressure intensifiers. For example, hydraulic cylinders in a mobile crane may need an output of 3,625 psi (250 bar) to lift loads as heavy as 20,000 lb (9,090 kg). Integrating a pressure intensifier could directly boost cylinders, while occupying just 4 in. of space at the same or even half the cost of a high-pressure vane pump.
Design considerations in mobile hydraulics go beyond space, of course. However, size is one of the most important aspects of decision making due to the constraints it imposes. Manufacturers and system engineers can keep machines lightweight without having to sacrifice performance by using compact, smarter alternatives to traditional hydraulic parts.
IC Fluid Power
icfluid.com
Filed Under: Components Oil Coolers, Cylinders & Actuators, Engineering Basics, Featured, Mobile Hydraulic Tips, Valves & Manifolds
