single acting vs double acting hydraulic pump free sample

Hydraulic cylinders provide the unidirectional force required to power your industrial equipment for heavy lifting. Telescopic hydraulic cylinders, which are ideal for dump trailers and platform truck trailers, give the extended stroke lengths required for a range of versatile purposes. When purchasing telescopic hydraulic cylinders, consumers are frequently faced with the decision between single-acting and double-acting hydraulic cylinders. Learn what distinguishes the two types of telescopic cylinders to determine which cylinder is appropriate for your high-power hydraulic requirements.

The hydraulic cylinder is the industrial world’s workhorse. Learn about the benefits and drawbacks of single and double-acting hydraulic cylinders. The function of your cylinder decides whether you should choose a single-acting or double-acting hydraulic cylinder.

Single-acting cylinders generate force exclusively in one direction, whether it is a push or pull action. These are also referred to as “plunger” cylinders. They are utilized in lifting operations where hydraulic pump pressure stretches the hydraulic cylinder and a mass or spring retracts it. Single-acting cylinders contain only one port through which the hydraulic pump’s pressurized oil passes. This causes the piston to extend in one direction, compressing the piston’s spring. After releasing the air via the cylinder port where it entered, the spring or associated mass will retract the piston rod.

Single-acting cylinders are classified into two types: push and pull cylinders. The push-type, as the name implies, will allow the air entering to push the piston out of the cylinder. The pull-type hydraulic cylinder allows the oil entering the cylinder to pull the piston inside the cylinder. For one-way linear movement, single-acting cylinders are ideal. They are commonly seen in hydraulic jacks and forklifts.

The lower manufacture, installation, and repair costs of single-acting hydraulic cylinders are an advantage. With only one port to operate instead of two, both piping and valve costs are significantly reduced.

The spring mechanism in single-action cylinder interiors necessitates venting, which provides the unit with an outlet to the outside world. Particles, on the other hand, can enter the cylinder and create potential malfunctions or a slow loss in performance if not adequately monitored.

Single-acting hydraulic cylinders are ideal for use with smaller equipment due to their single port and compact structure. Most of the time, if a smaller equipment design allows for ports, fluid transmission, and venting, then this cylinder will be extremely suitable.

Pressure flows from two ports in double-acting hydraulic cylinders. The “advance” hydraulic hose fitting connects to one of the ports. The pump’s hydraulic power forces the cylinder to extend via the first port. The “retract” hydraulic hose fitting is connected to the second port. Hydraulic power is used to extend and retract the cylinder in a double-acting hydraulic cylinder. In contrast to the single-acting cylinder, which produces force in only one direction, force is generated in both directions. As a result, the cylinder may both push and pull.

The piston rod moves due to the push and pulls forces created by the pressurized fluid that alternates between both sides of the piston. These hydraulic cylinders have more control over their movement in the application where they are installed. Using 2-, 3-, or 4-way position valves, different levels of movement can be produced. Double-acting hydraulic cylinders are utilized in mobile applications such as a TLB’s boom or to control the steering of an excavator.

Though this hydraulic cylinder is not appropriate for small places, double-acting hydraulics are extremely versatile. Two ports provide hydraulic power in both directions and are readily operated with a push-and-pull motion. As a result, they are the most popular hydraulic cylinder.

Unlike single-acting variants, double-acting cylinders are sealed from the outside world. As a consequence, you will not require repairs as a result of particles invading inside pipes and valves.

Precision work that needs hydraulic pistons to stop at specific lengths regularly can stretch and deform the hydraulics over time. However, double-acting hydraulic cylinders are constructed with exact, very precise dual ports, enhancing the product’s longevity.

The choice between a double-acting and a single-acting cylinder is frequently a matter of control. How precisely do you need to be while exerting force in your hydraulic system? A single-acting cylinder may be sufficient if you need to produce a large force to move a load in a single direction, such as in heavy lifting applications. However, if you need to direct a load in two directions or have more control over the cylinder’s movements, a double-acting cylinder will provide you with more control.

When comparing single-acting vs double-acting hydraulic cylinders, the most visible difference is the number of couplers or connection ports. A single-acting hydraulic cylinder includes just one port. This is where the hydraulic fluid enters and forces the plunger out in one direction. A double-acting cylinder includes two ports. One for the hydraulic fluid to enter and extend the plunger, and the other for retracting the cylinder.

The plunger in a single-acting hydraulic cylinder extends when hydraulic fluid under high pressure is pumped into the cylinder. When it is time to retract the cylinder, depending upon the cylinder design, the plunger can be retracted using a return spring, by the load, or simply by gravity.

In a double-acting hydraulic cylinder, the plunger retracts when hydraulic fluid is pumped under high pressure into the top port, forcing the plunger back to its original position. This can be done quickly, if required, or very gradually with precise control.

The single-acting cylinder is simpler than its double-acting counterpart. With fewer components, there is much less to go wrong, which is good news when it comes to maintenance.

Single-acting cylinders are ideal for straightforward jobs – especially when fast or controlled retraction isn’t essential. Hollow plunger versions including a thread are also available to handle pulling applications.

Double-acting hydraulic cylinders have the ability to pump hydraulic fluid to both sides of the plunger. Connection ports positioned near both ends allow the piston rod to move both forwards and backwards. The extra port also allows more control of the plunger during retraction and ensures it always returns back to its starting point.

Hydraulic cylinders are an essential component in many industries, including most of Australia’s critical sectors. Hydraulic cylinders and rams all provide the power a hydraulic system needs to function, but within the category of ‘hydraulic cylinders’, there are a few key types to understand.

The major way of dividing hydraulic cylinders is between ‘single acting cylinders’ and ‘double acting cylinders’. While fairly similar in function, there are differences between single and double acting hydraulic cylinders, meaning they aren’t interchangeable.

The main difference between single and double acting hydraulic cylinders is that a double acting hydraulic cylinder uses hydraulic pressure to move a piston in two directions, while a single acting hydraulic cylinder relies on a spring or gravity to return to its original position.

To help outline the differences in these fairly similar hydraulic systems, we have produced this handy guide. This article outlines the key differences between single and double acting hydraulic cylinders, and when is the best time to use each one.

Whether you’re choosing the right hydraulics components or need to repair hydraulic cylinders, you’ll need to know what type of cylinder or ram you’re working with. That’s why we’ve also covered how to identify single vs double acting cylinders and whether you can convert them.

A single acting hydraulic cylinder is a hydraulic cylinder in which the fluid acts only on one side of the piston. It relies on the springs, gravity, load, other cylinders, or separate reservoirs to push the piston back into the opposite direction.

The fluid used a type of oil (usually mineral oil), which allows the fluid to push a load without being compressed back down by the weight. This type of hydraulic cylinder is best for straightforward applications, where the goal is to have something move in one direction.

Push Type Hydraulic Cylinder– Fluid enters to push the piston out of the cylinder. This is also referred to as a hydraulic cylinder with a ‘sprung in’ position, where the piston is fully retracted at rest.

Pull Type Hydraulic Cylinder– Fluid enters to pull the piston inside the cylinder. This is also referred to as a hydraulic cylinder with a ‘sprung out’ position, where the piston rod is fully extended at rest.

In a single acting hydraulic cylinder, a plunger extends when the cylinder is pumped full of pressurised fluid. When it is retracted, the plunger can retract using a return spring, by the load or gravity.

Single acting hydraulic cylinders have only one port, where pressurised fluid enters. These are fitted with either a spring, or a load. When the fluid is compressed, it enters through the single port which forces the piston to extend in one direction, consequently compressing the spring. The spring then retracts the piston back into its previous position after releasing the fluid from through the same port it originally flowed from.

The typical applications of single acting hydraulic cylinders are simple lifting jobs, light industrial and commercial applications, and any other application where fast and consistent retraction is not essential.

Position And Line Up Objects – Through this application, a workpiece or product is either pulled or pushed into place, or into a specific machine such as a conveyor belt, before the spring acts and prepares the hydraulic cylinder for the next workpiece.

Punch Or Mark Objects– In this application, thrust from a single acting hydraulic cylinder is used to either punch or mark an object. The spring then retracts the punch, ready for the next object.

Keep in mind that double acting hydraulic cylinders are able to do all of the above, albeit without the cost savings of a single acting hydraulic cylinder. When it comes to hydraulic cylinder parts, single-acting cylinders are simpler and therefore cheaper to purchase.

Lower cost– The initial cost of single acting hydraulic cylinders is much lower than double acting ones. This makes it ideal for situations where a double acting hydraulic cylinder may be too much, and a single acting hydraulic cylinder will work fine. In addition, its single port and small housing leads to reduced valve and hose cost compared to double acting cylinders.

Easier maintenance – Since force is only applied to one direction, there are fewer areas or segments which have to be maintained. Single acting hydraulic cylinders are easier to maintain and repair, especially if you know how to maintain hydraulic cylinders.

Safety benefits– Single-acting hydraulic cylinders have a specific rest state, which can be easily identified in the event of a power outage. Knowing the cylinder’s resting state will prevent surprise and injury once power is restored, if the cylinder is halfway through an operating cycle.

International Standards –Compared to double acting hydraulic cylinders, there aren’t many single acting hydraulic cylinders that are compliant with ISO standards.

A double acting hydraulic cylinder is a hydraulic cylinder in which the fluid alternately acts on both sides of its piston. It has a port on each end, filled with hydraulic fluid for the pistons’ retraction and extension.

This type of hydraulic cylinder is ideal for applications that require fast and predictable retractions, or applications where consistent accuracy is necessary.

In a double acting hydraulic cylinder, the plunger retracts when the hydraulic fluid, which has now been pressurised, is injected into the top port, which forces the plunger back to its original position. It is possible for this process to be done either very quickly, or very gradually with precise control.

Double acting hydraulic cylinders have two ports where pressurised fluid can flow in and out. Fluid flows through one port, which moves the piston forward, which then applies pressurised fluid into the second port which then retracts the piston back into the cylinder.

The standard applications for double acting hydraulic cylinders are those that require repetitive presses and situations that require both pushing and pulling forces. Elevators and forklifts are good examples of double acting cylinder applications.

Double acting hydraulic cylinders can do anything a single acting cylinder can. However, these are especially good for industrial and robotics industries, tasks such as opening and closing doors, and lifting and moving merchandise off conveyor belts. Other uses include medical applications, earthmoving and construction equipment, and even in space programs.

Complexity– Double acting hydraulic cylinders are built slightly different to their single acting counterparts. The parts of a double acting cylinder are more complex. They generally have more pistons, and more seals to accommodate the flow of fluid on both ends for a push and pull control.

Costly– Double acting cylinders are much more expensive than their single acting counterparts. They require larger housing, for example, if it’s used as a feed cylinder and requires coupling with another machine system. Because the system is larger, fluid is often consumed at a faster rate than in single acting hydraulic cylinders.

Single and double acting hydraulic cylinders both serve similar functions, with the double acting hydraulic cylinder being able to do any job a single acting cylinder can, at the cost of being more expensive and requiring more dedicated maintenance.

Single acting hydraulic cylinders are simple, inexpensive, have one job they can do and do it well. These cylinders are exceptionally useful in fabrication, where one repetitive movement is required, such as on a factory line. Manufacturing hydraulics systems strongly rely on low-cost single acting cylinders.

Double acting hydraulic cylinders, in comparison, are far more sophisticated and powerful. Not only can a double acting cylinder perform any job a single acting hydraulic cylinder could, but by having the piston pressured to move in two opposing directions, it’s essential to the way modern pneumatic machinery works today. Things like elevators and forklifts could not exist without double acting hydraulic cylinders.

If an application only needs motion in one direction, a single acting hydraulic cylinder is the safest and most economical choice. However, any situation requiring greater control and power requires a double acting hydraulic cylinder, and the ISO standards compliance associated with them.

You have two general options when you need to use a hydraulic cylinder as part of your hydraulic system: single-acting or double-acting hydraulic cylinders. Both types are able to handle high-powered work to lift, move, pull, press, or complete other desired tasks.

A single-acting hydraulic cylinder has a single inlet connection for the hydraulic fluid. As the fluid flows into the cylinder, it pushes the cylinder piston rod to extend outwards in a single direction. Once the fluid flow stops the cylinder stops extending, when the valve operating the cylinder is reversed, a spring or gravity causes the piston to retract.

For example, the arms on a construction front loader could use a single-acting hydraulic cylinder to lift and raise the bucket on the front of the vehicle. When the line to the cylinder is opened to tank gravity, along with the weight of the bucket and its contents, will cause the piston inside the cylinders on the loader arms to retract and lower back down to the ground.

A double-acting hydraulic cylinder has dual inlet connections for the hydraulic fluid. Just like a single-acting hydraulic cylinder, one inlet will allow fluid to flow into the cylinder to extend the piston rod outwards to perform the designed work.

However, instead of relying on a spring or gravity to cause the piston to retract, hydraulic fluid is used. So, first, the fluid to the piston extension inlet is stopped. Then, hydraulic fluid is pumped into the second inlet on the other end of the cylinder to cause the piston rod to retract. As it does, the hydraulic fluid behind it is pushed back out through the inlet.

Double-acting hydraulic cylinders provide a bit more flexibility when controlling piston extension and retraction. It is easy to move the piston back and forth and ensure the plunger can be fully retracted to its original position.

In addition, work can be performed with double-acting cylinders somewhat faster since you do not have to wait for gravity or a spring to retract the piston.

Aside from how the piston rod is operated and having one or two hydraulic fluid inlets, there are some other differences between double-acting and single-acting hydraulic cylinders you need to know. By understanding these differences, it can help you choose the right hydraulic cylinder to meet your objectives.

Now that you have a better understanding of how double-acting hydraulic cylinders work and their pros and cons, let’s look at some of the key applications of using this type of cylinder for various applications.

For starters, double-acting cylinders are perfect for applications that require pressing, such as imprinting. The top pressure plates usually require the cylinder to be installed upside down. As such, the cylinders on the top pressure plate would not retract using a spring or gravity found in a single-acting cylinder.

Next, double-acting cylinders are well-suited for repetitive applications that need to be performed frequently—for example opening and shutting gates or doors. Operating the digger arms on backhoes or excavators.

Third, double-acting cylinders are better suited if you require a delayed or controlled reaction time as part of your hydraulic system functioning. Most importantly, if you desire the flexibility of pushing and pulling hydraulic operations, you will want to use double-acting cylinders.

Single-acting hydraulic cylinders have their useful purposes, too. They are a good choice for generalised lifting applications where springs or gravity can be used to retract the piston rod.

Another application for single-acting cylinders is whenever you do not require fast retraction and the cylinder is not being installed upside down. For instance, a hydraulic vehicle jack in a car service centre could use a single-acting hydraulic cylinder and rely on the weight of the vehicle to gradually cause the piston to retract.

In addition, single-acting cylinders are well-suited for a wide range of light commercial and industrial applications that require basic lifting or pushing movements. For example, some trash compactors use a single-acting hydraulic cylinder to compact the trash and a spring to retract the piston.

When choosing single-acting or double-acting hydraulic cylinders for your hydraulic system, you need to make sure that cylinders will perform the desired work and functions. It does not make any sense to invest in a single-acting cylinder when it will not perform the required work. Nor does it make sense to invest in a double-acting cylinder when a single-acting cylinder will meet your needs.

For example, if you need to move whatever is connected to the cylinders in two directions, then a double-acting cylinder is best. On the other hand, if you need to move the piston rod in a single direction and can rely on gravity or a spring for retraction, then a single-acting cylinder would be a good choice.

In addition, some system designs could use a combination of single-acting and double-acting cylinders depending on the system’s functions and applications. Last, you want to choose hydraulic cylinders that are built with high-quality parts and components that meet industry standards.

You can find the high-quality single-acting and double-acting hydraulic cylinders for every industry at White House Products, Ltd. Whether you need a single-acting cylinder for a light construction vehicle or double-acting cylinders for heavy industrial manufacturing purposes, we have or can make to your specification the cylinders you need.

We are also happy to help you choose which cylinders are best for your applications, as well as assist you with new hydraulic system designs. For further information, to request a free quote, or to order the cylinders you need, please feel free to contact us at +44 (0) 1475 742500 today!

A hydraulic pump converts mechanical energy into fluid power. It"s used in hydraulic systems to perform work, such as lifting heavy loads in excavators or jacks to being used in hydraulic splitters. This article focuses on how hydraulic pumps operate, different types of hydraulic pumps, and their applications.

A hydraulic pump operates on positive displacement, where a confined fluid is subjected to pressure using a reciprocating or rotary action. The pump"s driving force is supplied by a prime mover, such as an electric motor, internal combustion engine, human labor (Figure 1), or compressed air (Figure 2), which drives the impeller, gear (Figure 3), or vane to create a flow of fluid within the pump"s housing.

A hydraulic pump’s mechanical action creates a vacuum at the pump’s inlet, which allows atmospheric pressure to force fluid into the pump. The drawn in fluid creates a vacuum at the inlet chamber, which allows the fluid to then be forced towards the outlet at a high pressure.

Vane pump:Vanes are pushed outwards by centrifugal force and pushed back into the rotor as they move past the pump inlet and outlet, generating fluid flow and pressure.

Piston pump:A piston is moved back and forth within a cylinder, creating chambers of varying size that draw in and compress fluid, generating fluid flow and pressure.

A hydraulic pump"s performance is determined by the size and shape of the pump"s internal chambers, the speed at which the pump operates, and the power supplied to the pump. Hydraulic pumps use an incompressible fluid, usually petroleum oil or a food-safe alternative, as the working fluid. The fluid must have lubrication properties and be able to operate at high temperatures. The type of fluid used may depend on safety requirements, such as fire resistance or food preparation.

Air hydraulic pump:These pumps have a compact design and do not require an external power source. However, a reliable source of compressed air is necessary and is limited by the supply pressure of compressed air.

Electric hydraulic pump:They have a reliable and efficient power source and can be easily integrated into existing systems. However, these pumps require a constant power source, may be affected by power outages, and require additional electrical safety measures. Also, they have a higher upfront cost than other pump types.

Gas-powered hydraulic pump:Gas-powered pumps are portable hydraulic pumps which are easy to use in outdoor and remote environments. However, they are limited by fuel supply, have higher emissions compared to other hydraulic pumps, and the fuel systems require regular maintenance.

Manual hydraulic pump:They are easy to transport and do not require a power source. However, they are limited by the operator’s physical ability, have a lower flow rate than other hydraulic pump types, and may require extra time to complete tasks.

Hydraulic hand pump:Hydraulic hand pumps are suitable for small-scale, and low-pressure applications and typically cost less than hydraulic foot pumps.

Hydraulic foot pump:Hydraulic foot pumps are suitable for heavy-duty and high-pressure applications and require less effort than hydraulic hand pumps.

Hydraulic pumps can be single-acting or double-acting. Single-acting pumps have a single port that hydraulic fluid enters to extend the pump’s cylinder. Double-acting pumps have two ports, one for extending the cylinder and one for retracting the cylinder.

Single-acting:With single-acting hydraulic pumps, the cylinder extends when hydraulic fluid enters it. The cylinder will retract with a spring, with gravity, or from the load.

Double-acting:With double-acting hydraulic pumps, the cylinder retracts when hydraulic fluid enters the top port. The cylinder goes back to its starting position.

Single-acting:Single-acting hydraulic pumps are suitable for simple applications that only need linear movement in one direction. For example, such as lifting an object or pressing a load.

Double-acting:Double-acting hydraulic pumps are for applications that need precise linear movement in two directions, such as elevators and forklifts.

Pressure:Hydraulic gear pumps and hydraulic vane pumps are suitable for low-pressure applications, and hydraulic piston pumps are suitable for high-pressure applications.

Cost:Gear pumps are the least expensive to purchase and maintain, whereas piston pumps are the most expensive. Vane pumps land somewhere between the other two in cost.

Efficiency:Gear pumps are the least efficient. They typically have 80% efficiency, meaning 10 mechanical horsepower turns into 8 hydraulic horsepower. Vane pumps are more efficient than gear pumps, and piston pumps are the most efficient with up to 95% efficiency.

Automotive industry:In the automotive industry, hydraulic pumps are combined with jacks and engine hoists for lifting vehicles, platforms, heavy loads, and pulling engines.

Process and manufacturing:Heavy-duty hydraulic pumps are used for driving and tapping applications, turning heavy valves, tightening, and expanding applications.

Despite the different pump mechanism types in hydraulic pumps, they are categorized based on size (pressure output) and driving force (manual, air, electric, and fuel-powered). There are several parameters to consider while selecting the right hydraulic pump for an application. The most important parameters are described below:

Speed of operation: If it is a manual hydraulic pump, should it be a single-speed or double-speed? How much volume of fluid per handle stroke? When using a powered hydraulic pump, how much volume per minute? Air, gas, and electric-powered hydraulic pumps are useful for high-volume flows.

Portability: Manual hand hydraulic pumps are usually portable but with lower output, while fuel power has high-output pressure but stationary for remote operations in places without electricity. Electric hydraulic pumps can be both mobile and stationary, as well as air hydraulic pumps. Air hydraulic pumps require compressed air at the operation site.

Operating temperature: The application operating temperature can affect the size of the oil reservoir needed, the type of fluid, and the materials used for the pump components. The oil is the operating fluid but also serves as a cooling liquid in heavy-duty hydraulic pumps.

Operating noise: Consider if the environment has a noise requirement. A hydraulic pump with a fuel engine will generate a higher noise than an electric hydraulic pump of the same size.

Spark-free: Should the hydraulic pump be spark-free due to a possible explosive environment? Remember, most operating fluids are derivatives of petroleum oil, but there are spark-free options.

A hydraulic pump transforms mechanical energy into fluid energy. A relatively low amount of input power can turn into a large amount of output power for lifting heavy loads.

A hydraulic pump works by using mechanical energy to pressurize fluid in a closed system. This pressurized fluid is then used to drive machinery such as excavators, presses, and lifts.

A hydraulic ram pump leverages the energy of falling water to move water to a higher height without the usage of external power. It is made up of a valve, a pressure chamber, and inlet and exit pipes.

A water pump moves water from one area to another, whereas a hydraulic pump"s purpose is to overcome a pressure that is dependent on a load, like a heavy car.

Hydraulic cylinders are used in various mobile applications such as dump trucks, excavators, graders, loaders, dozers, and backhoes. Types of these hydraulic cylinders vary in certain components including the material, operating pressure, procedures used for connecting end caps, temperature, and wall thickness of tube or end caps.

Hydraulic cylinders are one of the most important components of the hydraulic industry. In order to convert the incompressible hydraulic fluid energy to work, hydraulic cylinders are used.

A hydraulic cylinder is a linear actuator that helps in generating an automatic force in a straight line either by pulling or pushing. The manufacturing of hydraulic cylinder requires many components. They include:A tube with finished interior and hard chrome-plated piston rods used to prevent pitting and scoring

Hydraulic cylinders are used in various mobile applications such as dump trucks, excavators, graders, loaders, dozers, and backhoes. Apart from this, hydraulic cylinder also has other applications including gym equipment, heavy machinery, wheelchair lifts, and many others. These beneficial features of the hydraulic cylinders have increased its demand in the end-use industries. A recent report by Research Dive, the global hydraulic cylinders market is anticipated to generate a significant revenue in the forthcoming years.

Hydraulic cylinders come in a wide type range. The design of cylinders differs depending upon its applications and end-use industries. Types of these hydraulic cylinders vary in certain components including the material, operating pressure, procedures used for connecting end caps, temperature, and wall thickness of tube or end caps. Some of the most important cylinder types include single acting cylinders, double acting cylinders, welded rod, tie-rod, and telescopic cylinders. Let’s have brief insights about each of them:

This type of cylinder is referred to as single acting cylinder because the head end port of these cylinders works in a single direction. As soon as the liquid gets pumped into the cylinder barrel, it will extend the piston rod. An external force or a load string is needed for the generation of the return operation. Then external energy is used to drain the fluid from barrel to the reservoir. An example of the single acting cylinder is a hydraulic jack.

Single acting cylinders are divided into two types- spring-extend and spring-return. Spring-return is the most commonly used type of single acting cylinder.

Double acting cylinders are designed with ports in both the head and rod ends which make it easier to pump fluid. The ports will control the flow of the liquid and encourage movement in both ways. When the hydraulic fluid is pumped to the rod end, the piston rod is retracted. On the other hand, pumping the fluid to the head end will help in extending the piston rod. Applications of this type include the raising and lowering devices. Two main categories of double acting cylinders are differential type and synchronous types.

Telescopic cylinders can be single or double acting. This type of cylinder homes more than five tubings. This is a single or double acting cylinder. Telescopic cylinder comprises more than five tubings. Each of these tubings nests inside one another. The diameter of each of these nested tubings or stages becomes lesser.

The hydraulic cylinders are rising in demand because of their applicability in various industries. With technological advancements, the hydraulic cylinders are expected to be more efficient in upcoming years.

There are two most commonly used types of hydraulic cylinder: single acting and double acting cylinders. One type of cylinder is not innately better than the other and the decision is not normally an either/or choice.

Rather, both single and double acting cylinders have their uses and applications where they are better suited than the other type. In this article we take a brief look at each type, explaining how they work and the applications they are found in.

In a single acting hydraulic cylinder, fluid pressure is exerted on one side of the piston only, so that the piston rod acts like a hydraulic ram, pushing outwards but not pulling back on the retract movement. These cylinders need an external force to retract the piston rod, such as a pump, motor or set of internal springs.

While high quality single acting hydraulic cylinders are reliable units, those equipped with retractable springs are vulnerable to component failure as the springs wear out. This manifests as a gradual reduction in force on the retract movement. They are also more difficult to seal and can become damaged over time through exposure to corrosive fluids.

A double acting cylinder is capable of pressure being exerted on either side of the piston alternatively. This means that both outward and retraction movements can be achieved under the cylinder’s own pressure without an external source of power. This can be used simply to return the piston to its starting position, or to apply an alternating force on both sides of the cylinder – for instance to operate a crankshaft.

The decision between a double acting or single acting cylinder often boils down to one of control. How much precision is required when exerting force in your hydraulic system? If you need to exert a large force to move a load in a single direction – e.g. for heavy lifting applications – a single acting cylinder may be sufficient. However, if you need to direct a load in two directions or have greater flexibility over the movements of the cylinder, a double acting cylinder will give you more control.

We have a range of single acting and double acting hydraulic cylinders available for immediate dispatch from our extensive stock. Click here to check our current availability. For questions and product enquiries, please call 01299 896953.

The Power Team P-Series hand pumps come in a variety of configurations to meet the requirements of your application.  Along with various oil capacities and flow rates, you can choose from the following options:

Compact design ensures that the Power Team PA6 series pump is lightweight and portable. The PA6 series consists of single-speed pumps designed to drive single-acting cylinders. The power unit of choice for major manufacturers of auto body, frame straighteners and other equipment. Operates at 40-100 psi (3-8 bar) shop air pressure at the pump, dBA 85 at 10,000 psi (700 bar). Serviceable pump motor is not a “throwaway”, providing economical repair. Permanently vented reservoir cap. Internal relief valve protects circuit components, air inlet filter protects motor.

Compact, lightweight and portable the Power Team PA6D series pumps are single-speed pumps for driving double-acting cylinders. The PA6D series pumps operate at 40-100 psi (3-8 bar) shop air pressure at the pump. Designed with longevity in-mind the PA6D series feature internal relief valve protects circuit components, air inlet filter protects motor. Serviceable pump motor is not a “throw away”, providing economical repair. Permanently vented reservoir cap. dBA 85 at 10,000 psi (700 bar) for all PA6 pump.

Ideal for powering single-acting cylinders and portable hydraulic tools, the Power Team PA9 series pumps are easier to operate than a hand pump, designed for efficiency. Built to be economical in service; the PA9 series is not a “throwaway” unit. Unique bladder design for all-position operation and storage. Operates on 40-120 psi (3-8 bar) shop air, at 20 cfm (570 l). Hard-coat anodized aluminum housing. Oil filler with integral safety relief minimizes chance of damage to reservoir bladder if overfilling occurs.

A two-speed pump, the Power Team PA60 series pumps are designed for rapid oil delivery at low pressure to quickly advance cylinder or tool. Equipped with air pressure regulator, air filter and lubricator. Serviceable air motor for economical repair. Internal relief valve protects circuit components. Permanently vented reservoir cap.

Focused on single-speed and low pressure the Power Team PA50 series pump outputs 3,200 PSI / 220 BAR, fitting serviceable requirements for air motor for economical repair. Integrated air inlet filter protects motor. The PA50 series also features a filter in outlet port protects against contaminated systems Assorted reservoirs to suit your application"s requirements.

Rotary-Style Air Motor.  Use where air is the preferred source of energy.  3 hp motor starting under full load.  Two-speed operation for rapid cylinder advance.  Models available with full remote control over advance and return, except PA554.  Tandem center valve holds the load when pump is shut-off.

Compact, Portable, Cordless Hydraulic Pump for MRO Applications.  Compact, Li-ion 18VDC, 9.0 Ah battery-powered pump provides extended run-time.  Two-stage, high-pressure hydraulic pump offers quick tool advancement in the first stage.  Extremely compact, lightweight with an ergonomic handle grip and transport strap to ease portability.  Self-contained, rubber bladder reservoir allows pump usage in most positions with an impressive capacity of 70 cu. in. usable.  Quiet, smooth-running, serviceable brushed 18VDC motor.  High-impact, fiberglass reinforced shroud protects your investment in the most demanding and harsh applications.  Interchangeable valve configuration accommodates a vast array of applications.  CSA rated for intermittent duty, CE compliant.

The 10 series Power Team hydraulic pumps are designed to have a maximum of 690 bar (10,000 psi) at a flow rate of 164 cc/min (10 cu. in/min). All Power Team pumps come fully assembled, and each with the ability to be valved for either single- or double acting cylinders. Designed to be compact can easily mobile, the power team 10 series includes a portable power source is included for hydraulic cylinders, and tools. The permanent magnet motor is strategically constructed to easily start under load, even with reduced voltage conditions. Battery-operated models have 8 foot (2,4 m) power cord with alligator clips to connect to any 12 volt battery, optional rechargeable battery pack with shoulder strap are alternatives for maximum portability. The Power Team 10 series pump typically delivers 15 minutes of continuous operation at 10,000 psi (700 bar) on a single battery. Built to withstand High-impact, shielded with a flame retardant construction.

The Power Team 17 series pump is delibertly designed for maintenance and construction applications up to 55 Ton. For use with single-acting or double-acting cylinders at operating pressures to 10,000 psi (700 bar). For intermittent duty; starts under full load. Equipped with 1⁄2 hp (0,37 kW), 3,450 rpm, single-phase, thermal protected induction motor; 10 ft. remote control cord (PE172S has 25 ft. (7,6 m) cord) Low amperage draw; small generators and low amperage circuits can be used as power source. Extremely quiet noise level (67-81 dBA).

Vanguard Jr. + Power Team 18 series pumps provide two-speed high performance in a light-weight, compact package. Designed to provide a gauge port and metal reservoir on all pump models. Equipped with a 1⁄2 hp (0,37 kW), 115 volt, 60/50 Hz single phase motor that starts under load, even at reduced voltage. Low amperage draw permits use with smaller generators and low amperage circuits. All pumps have a 10 foot (3 m) remote control. CSA rated for intermittent duty. Noise level of 85-90 dBA. For operating hydraulic crimping, cutting or other tools: No. PE184C - Allows you to alternately operate a spring-return cutting and/or crimping tool without disconnecting either tool. Select a port connection with a manual 4-way valve, start the pump with a remote control hand switch and extend the connected tool. When the hand switch is switched to off, the pump stops and the automatic valve opens, allowing the tool to return. In the center (neutral) position, a manual control valve holds the tool in position at the time valve is shifted.

The 21 series Power Team pump and RD5513 cylinder used in a special press that produces pharmaceutical-grade extracts for herbal medicines. Totally enclosed, fan cooled induction motor: 1 hp (0,75 kW), 1,725 rpm, 60 Hz, single phase. Designed intentional for thermal overload protection. Remote control, with 10 foot (3,1 m) cord is standard on pumps with solenoid valves. Manual valve pumps have “Stop”, “Start” and “Run/Off/Pulse” switches. Pump controls are moisture and dust resistant. Motor drip cover with carrying handles and lifting lug. Low noise level of 70 dBA@ 10,000 psi (700 bar). In the event of electrical interruption, pump shuts off and will not start up until operator presses the pump start button. 24 volt control circuits on units with remote controls provide additional user/operator safety.

Ideal for running multiple tools or cylinders from one power unit. Recommended for cylinders up to 75 tons. Two-speed pumps have the same low pressure and high pressure flows from both valves. Flows and pressures of each pump are independent. Delivers 300 cu. in./min. of oil at 100 psi (4,8 liter/min of oil at 7 bar) and 25 cu. in./min. at 10,000 psi (0,4 liter/min at 700 bar) from each pump. 1 1/2 hp, 110/115 volt, 60 Hz (1,12 kW, 220 volt, 50 Hz) induction motor, 10 foot (3,1 meter) remote control and 5 gallon (19 liter) steel reservoir. Models available for operating single-acting or double-acting cylinders. Each power unit contains two separate pumps and two separate valves allowing operator to control multiple processes with one power unit. Both pumps on each power unit are equipped with an externally adjustable pressure relief valve. Not recommended for frequent starting and stopping.

The Power Team 30 series pump is intently ideal for maintenance and construction applications.  Operating both single-acting or double-acting cylinders. A dynamically built, Integral roll cage protects the 30 series pump from many forms of damage. 1 hp (0,75 kW), single phase, permanent magnet motor. High performance to weight ratio. Starts under full load even when voltage is reduced to 50% of nominal rating. Quit operations: 82 dBA @ 10,000 psi (700 bar) and 87 dBA @ 0 psi (0 bar). CSA rated for intermittent duty. Remote controls and/or solenoid valves feature 24 volt controls.

The Power Team 46 series is best suited for under the roof maintenance and production applications. Equipped with two-speed high-performance pump, for use with single- or double-acting cylinders at operating pressures to 10,000 psi (700 bar) the 46 series pump is versitile. With a 1 1⁄2 hp (1.12 kW), 3,450 (2,875) rpm single-phase, 60 (50) Hz thermal protected induction motor that starts under full load. Noise level of 77-81 dBA. All equipped with a 10 foot (3,1 m) remote control except PE462S which has a 25 foot (7,6 m) remote control. 24 volt control circuit on all units with remote control. CSA rated for intermittent duty.

A powerful multifaceted pump, the Power Team 55 pump excels at multiple applications. From heavy construction to concrete stressing this pump series is designed for intensity. With low voltage starting possible,  the 50/60 Hz universal motor; draws 25 amps at full load, and can start at reduced voltage. CSA rated for intermittent duty. 10 foot (3,1 m) remote motor control (except PE552S which has a 25 foot (7,6 m) remote motor and valve control). True unloading valve achieves greater pump efficiency, allowing higher flows at maximum pressure. Reservoirs available in sizes up to 10 gallons (38 liter). Lightweight and portable. Best weight-to-performance ratio of all Power Team pumps. “Assemble to Order” System: There are times when a custom pump is required. Power Team’s “Assemble to Order” system allows you to choose from a wide range of pre-engineered, off-the shelf components to build a customized pump to fit specific requirements. By selecting standard components you get a “customized” pump without “customized” prices. All pumps come fully assembled, add oil and ready for work.

A compact lightweight pump, the Power Team 60 series is designed for rugged applications and low voltage starting. Experiencing a long, trouble-free life in the most demanding work environments, the 60 series is durable.. Powered by 1 1⁄8 hp, 115 volt, 60/50 Hz (0,84 kW, 220 volt, 60/50 Hz) single phase motor. Starts under load, even at the reduced voltages at construction sites. Optional fan-driven external oil cooler includes rollover guard. Insulated carrying handle. Integral 4" (102 mm) diameter fluid-filled pressure gauge with steel bezel complies with ASME B40.1 Grade A. 0 to 10,000 psi (0 to 700 bar) pressure range in 100 psi (7 bar) increments. Sealed 3⁄4 gallon (4,34 liter (usable) reservoir. Reservoir drain port is standard. Standard oil level sight gauge for accurate oil level monitoring. External spin-on filter removes contaminants from circulating oil to maximize pump, valve and cylinder/tool life.

The Power Team PQ60 series pumps are designed specifically for heavy-duty, extended cycle operation. Integrating single- or double-acting cylinders the PQ60 series is versatile. Constructed for longevity by employing a metal shroud keeps dirt and moisture out of motor and electrical components. An electrical shut-down feature prevents unintentional restarting of motor following an electrical service interruption. Internal relief valve limits pressure to 10,000 psi (700 bar). External relief valve is adjustable from 1,000 to 10,000 psi (70 to 700 bar). The Power Team PQ60 pumps operate below maximum OSHA noise limitation (74-76 dBA). Start and operate under full load, even with voltage reduced by 10%.

The Power Team 120 series pump is exactingly designed for heavy duty, extended cycle operation up to 400 Ton. Built in grit, the series 120 pump can start and operate under full load, even with voltage reduced 10%. An electrical shut-down feature prevents unintentional restarting of motor following an electrical service interruption. Internal relief valve limits pressure to 10,000 psi (700 bar) and an external relief valve is adjustable from 1,000 to 10,000 psi (70 to 700 bar). Pump prewired at factory with a 3 hp, 460 volt, 60 Hz (2,24 kW, 380 volt, 50 Hz), 3 Phase motor. Other electrical configurations are available. 24 volt control circuits on units with remote controls for added user/operator safety. 3 hp (2,24 kW) 3 phase motor with thermal overload protection. Motor starter and heater element supplied as standard equipment; with an intentionally designed metal shroud to keep dirt and moisture out of motor and electrical components. Pumps operate below maximum OSHA noise limitation.

With high tonnage double-acting cylinders, the Power Team 400 series offers both single or multiple cylinder applications. Two-speed high output pump delivers up to 5 gpm (16 liter/min) of oil, with a low noise level of 73-80 dBA. Integral electrical shut-down feature prevents unintentional restarting of motor following an electrical service interruption. Over-current protection prevents damage to motor as a result of overheating. “Stop” and “Start” control buttons are 24 volt. PE4004 has a 4-way/3-position manual valve. The PE4004S has a 4- way/3-position solenoid valve with a 24 volt remote hand switch. External pressure relief valve is adjustable from 1,500 to 10,000 psi (100 to 700 bar). Heavy duty 4" (50,8 mm) diameter casters assure easy maneuvering. 20 gallon (3,927 cu. in. usable) / 75,7 liter (62,8 liter usable) reservoir has a low oil level sight gauge. Powered by a dual voltage 10 hp (7,46 kW), 3 phase, 1,725 (1,437) rpm motor. 3 phase motor has all the electrical components necessary to operate the pump.The customer has no hidden charges when making purchase. Deliver 1,200 cu. in./min. (16 liter/min) of oil @ 200 psi (15 bar), 420 cu. in./min. (5,6 liter/min) of oil @ 10,000 psi (700 bar).

Power team synchronized lifting and lowering system, the MCS ( motion controller system ) series can be used in many hydraulic applications where load position is critical, requiring cylinder synchronization. Whether it is a bridge, a building or any kind of heavy load, with the SPX FLOW power team motion control system, lifting, lowering, pushing, pulling, tilting or positioning loads can be carried out automatically with a high degree of accuracy. The PLC-controlled system is a combination of digital actuation and digital control providing significant advantages such as time savings, repeatability, and extremely low internal stress in the object one is moving. The system also provides documentation for the movement performed.

Extremely durable yet lightweight and operable under low-line voltage conditions, the Power Team PE-NUT series pumps are constructed for challenging conditions. A 115V 5/8 hp (0,46 kW) universal electric motor (50/60 cycle), employing a two-stage pump for efficiency and designed for use with spring-returned remote tools. The PE-NUT series pumps also feature high-pressure safety relief valve, remote hand control with 10-foot (3,1 meter) cord, and a pressure matched quick-coupler supplied. The PE-NUT series uniquely utilizes intermittent duty, piston-type high-pressure pump supercharged by a low-pressure pump. CAUTION: DESIGNED FOR CRIMPING APPLICATION ONLY! This system should not be used for lifting.

Gasoline power ideal for remote locations.  A logical choice at work sites where electricity or compressed air are unavailable. For single or double-acting cylinders at operating pressures up to 10,000 psi.  All gasoline engine/hydraulic pumps feature Posi-Check® valve to guard against pressure loss when valve is shifted from “advance” to “hold.”

PG303 is for single-acting cylinders, has a 9520 valve with separate internal return line which allows oil from running pump to return to reservoir, independently of cylinder return oil, when valve is in “return” position.

A logical choice at work sites where electricity or compressed air are unavailable. For single or double-acting cylinders at operating pressures to 10,000 psi.

PG1200 Series pumps powered by a Honda 4-cycle, 5.5 hp engine with automatic decompression and electronic ignition. Deliver over 0.5 gallon (130 cu. in.) of oil per minute at 10,000 psi.

Rubber anti-skid insulation on bottom of reservoir resists skidding and dampens vibration. PG1200M-4 and PG1200M-4D include a pump cart with 12” wheels.

The Power Team HB series is purposefully constructed to convert low-pressure portable hydraulic pumps or on-board hydraulic systems, into high pressure power sources. HB series applications include utilities, railroads, construction, riggers and others. This product operates single or double-acting cylinders, jacks, and tools such as crimpers, spreaders, cable cutters, or tire tools. Version for use with double-acting torque wrenches available. May be used to operate two separate, single-acting tools (with integral valves) independently, without need for additional manifold. Control valve included. Other Power Team valves available as an option to suit your specific application, if needed; consult factory. Compact and rugged for use inside a utility vehicle aerial bucket or stowing in a vehicle. No reservoir level to maintain; uses low pressure system as oil supply. Has 3⁄8" NPTF ports; compatible with standard fittings for low and high pressure systems.

Portable two-speed pump operated in any position (open or closed-center) providing pressures up to 10,000 psi for the operation of high-pressure tools.

These compact, lightweight boosters do not have reservoirs. The units can be operated in any position on either open- or closed-center (accumulator) hydraulic systems.

“Assemble to Order” means you can choose a basic pump with gas, air or electric motor. Then select the proper valve, gauge, pressure control, motor control and reservoir. You get a two-stage pump that gives high oil volume for fast cylinder approach (and return with double-acting cylinders) in the first stage and high pressure in the second stage.

1-1/8 HP Universal Motor.  These motors start under full load and are suitable for operation up to 5,000 or 10,000 psi. The motor is 1-1/8 hp, 12,000 rpm, 115 or 230VAC (specify), 50/60 cycle AC single-phase (25 amp draw at 115VAC). With proper valve they can be used with single or double-acting cylinders. NOTE: Remote control available.

1-1/2 HP Jet Motor, Single & Three-Phase.  Feature low noise level, moderate speed for long service and are ideal for fixed applications. Motor is 1-1/2 hp, 3,450 rpm, 115 or 230VAC, 50 or 60 cycle (specify), AC single-phase with thermal overload switch. Can be used with single or double-acting cylinders and equipped with remote control. Also available in 230/460VAC, three-phase (specify).  NOTE: These do not start under full load unless valve is in “neutral” (requires open or tandem center valve) and are not recommended for frequent starting and stopping.

3 HP Jet Motor, Three-Phase.  Gives low noise level and long life due to its moderate operating speed. Ideal for fixed installations. Consists of basic 10,000 psi pump, jet pump motor: 3 hp, 3,450 rpm, 230/460VAC, 60 or 50 cycle (specify). AC three-phase, with thermal overload switch. Equipped with internal and external relief valve. Will start under load.

or cannot be used. The 5,000 or 10,000 psi pump has a 3 hp air-driven motor at 3,000 rpm (optimum performance based on 80 psi air pressure and 50 cfm at the pump). You can drive single or double-acting cylinders with the correct valve.  NOTE: 80 psi air supply required to start under full load.

unavailable. It is capable of continuous operation at full pressure. Consists of basic 10,000 psi pump, 4-cycle Briggs & Stratton “Diamond Edge” gasoline engine, developing 6 hp. As with all these pumps, this unit can be valved for use with either single or double-acting cylinders.

A double acting cylinder uses hydraulic power to both extend and retract. You can tell if a cylinder is double acting by looking at the number of ports. See the image below as an example.

A double acting cylinder has pressing and pulling power and is generally controlled with a joy stick control. A single acting cylinder only has pressing power.

A hydraulic cylinder is a tube that produces linear actuation utilizing hydraulic pressure. Basically, the pressure of a hydraulic fluid forces a piston to move in either a pushing or pulling motion.

Because hydraulic fluids are incompressible, the plungers A1 and A2 will remain in the same positions if no force is exerted on any of them. But if a force is exerted on one of them, we will notice a displacement on the other end because of a resultant force calculated using Pascal‘s Law as follows.

Hydraulic cylinders are the moving force in many commercial as well as industrial manufacturing concerns. Some of their applications are as detailed below:

Depending on the application and industry, hydraulic cylinders can be called hydraulic actuators or hydraulic pistons. These terms can be understood in the following contexts:

In instances where large amounts of force are needed to operate a valve e.g., valves of a mainstream system, hydraulic actuators are the preferred choice. Hydraulic actuators come in various orientations but the most common is the piston type.

Small hydraulic cylinders have a stable structure, are easy to operate and can be used for a much extended period of time. They are typically used in fast motion applications as well as in equipment with intricate and small components.

Stainless steel hydraulic cylinders are typically used in applications where the priority is corrosion resistance. The vast majority of other hydraulic cylinders are made from alloy steel combinations such as 1045 and 1018. However, they are prone to oxidation and rusting when used in wet or humid environments. The carbon steel cylinders can still be prone to dents, surface abrasion, or harsher chemicals, even if they may be painted using epoxy. Thus, such conditions can wear away the paint and expose the carbon steel to corrosion. Therefore, in such instances stainless steel hydraulic cylinders are preferred, for example in marine environments both onshore and offshore. These can be used on maritime cranes, davits, or boat lifts.

Hydraulic Cylinders come as either Single or Double Acting. If only one chamber is pressurized by the hydraulic fluid, it is a single acting, otherwise it‘s double acting.

In a single acting cylinder, there is one chamber that receives pressurized hydraulic fluid. Which side that is will depend on the intended use of the cylinder. If it is meant for a pushing motion, the chamber opposite the cylinder rod will be pressurized. The other chamber is usually spring loaded to cater for the retraction. If the chamber with the cylinder rod is the one pressurized, it will be a pull motion. The opposite chamber will also be spring loaded to cater for the protrusion.

In a double acting cylinder, both chambers can be pressurized. Of the two chambers, the one that accommodates the cylinder rod will have little surface in contact with the hydraulic fluid, since we cannot take into account the surface area of the piston already occupied by the cylinder rod. This difference in the surface area will need less pressure to retract than the other. Thus, pressure control and direction control is important in this set up of hydraulic systems.

The three most popular hydraulic piston configurations are ram styles, tie-rod, and welded. Tie-rod cylinders utilize threaded steel tie-rods with great strength, usually on the outside of the cylinder casing, to provide additional stability. Welded cylinders incorporate a heavy-duty welded cylinder housing that has a barrel welded right onto the end caps and thus requires no tie rods. Ram cylinders usually have no piston but rather use the cylinder rod as the piston.

Single-acting hydraulic cylinders that have no pistons but have large rods are called rams. These rams operate exactly like the conventional single-acting cylinders. However, they use large diameter rods in place of pistons and piston seals in their designs. Thus, in place of pistons, rams have high-pressure cap-end ports. They also do not have any low-pressure rod-end ports.

Ram types of hydraulic cylinders are typically used to give vertical motion, including lifting loads in a vertical direction. Such a cylinder is also used to provide the motion in a horizontal direction but needs attention and suitable guides to guide the motion.

Telescopic hydraulic cylinders are also known as multi stage cylinders. Their huge advantage is that it can be a single acting hydraulic cylinder or a double acting hydraulic cylinder or a combination of both. They are a variant of a linear actuator with stages operated in a straight line rather than circular. Telescopic cylinders are typically used in construction trucks, dump trucks, vehicle trailers, and agricultural equipment. The telescopic hydraulic cylinders can be operated with ease, cost effective, space saving and can meet specific angle requirements.

As the hydraulic pressure is introduced to the cylinder, the main or barrel, which is the largest sleeve, is extended first. Once the barrel has gotten to its maximum stroke, the next sleeve then begins to extend. This will continue until the cylinder reaches the last stage.

In a welded rod hydraulic cylinder, often the barrel gets welded directly to the end caps. The head cap can utilize a variety of retention approaches, such as threading or bolting down. This design is generally accepted for mobile equipment because of the compact construction, inside bearing lengths, and its duty cycle compared to tie rod construction. But, this design does make inspection and repairs a lot more difficult in the field due to requiring less common tools and equipment.

The welded rod cylinders are welded and also have loftier seal packages. These help to increase the life expectancy of the cylinder and are helpful when the cylinder will be used in locations that include contaminants and weathering. Visually, these welded body cylinders tend to have lower profiles than tie rod cylinders which improves the appearance of the equipment they are mounted on. Because they are narrower than tie rod ones, welded hydraulic cylinders work well in situations where space is a factor.

This is the main case of the cylinder. Made of steel, commonly carbon steel, the barrel or cylinder tube is built to withstand hydraulic fluid pressure inside its walls throughout its lifespan. A wide variety of steel qualities are available that offer ruggedness and strength, but basically greater pressures will require thicker cylinder walls and stronger steels.

To prevent corrosion and abrasion, the surfaces are given special treatment. Either these will be coated or painted. Some applications of hydraulic cylinders like food packaging might need a material without coats to avoid peels falling into the food, thus stainless steel can be employed in such cases. The internal walls usually need no surface finishing because the hydraulic liquid is usually non corrosive and also protects it from corrosion. However, in some cases where water is used as the hydraulic fluid, coating may be required on the inside walls as well.

This is the part that protrudes out of the barrel. It is attached to the piston inside the cylinder. Because of the friction from the rapid protruding and retracting, this is the only external component that is not painted. Because of its function, not only does it need protection from corrosion, but wear and pitting. This is a very delicate component because peeling, pitting, or corrosion will most likely scrap the seals, contaminate the hydraulic fluid and eventually jeopardize the whole hydraulic systems.

So, the materials and coating of the hydraulic cylinder are of the highest importance. Usually, the cylinder rod is machined from steel or stainless steel and the