Get in touch today to discuss your requirements
Call: (+44) 01452 523352
Our current blog looks at Hydraulic Cylinders and acts as a guide to help you choose the correct type of cylinder for your hydraulic system.
As system layouts and sizes vary greatly, it can be a bit of a trial and error process to get the correct measurements for fitment. Luckily some manufacturers, such as ourselves, offer a bespoke cylinder option which can be tailored to specific power units with additional options also available, if required.
We will start with the most common type of cylinder, sometimes known as a catalogue cylinder, as they typically come in a range of pre-set measurements so you can browse through the standard sizes to find the best fit for your system. These are especially popular for smaller systems where the operational length of the system isn’t a big concern.
Standard cylinders can be a cheap, cost effective solution, but you have to bear in mind that if you have cut corners to get a non-bespoke cylinder, you may lose some of the extra efficiency and reliability a custom built cylinder could offer.
Next up are the bespoke cylinders themselves; the advantage of these is that they can be factored into the design of a system so form and function are perfectly suited to your custom build.
There are a number of key areas to look at when designing your bespoke cylinder. These include:
Servicing and maintenance plays a big part in ensuring that your cylinder is in prime working condition and with standard cylinders where ports and other components come pre-positioned, being able to service the cylinder easily could become a problem, whereas with bespoke versions the layout of componentry has been optimised to work closely with the system, thus maintenance is more straight forward.
At Hydraproducts we sell both standard and bespoke cylinders and these now form part of our new Components Division, which you can find out more about by clicking here to visit our new Hydraulics components webpage where Cylinders, Valves, Accumulators and more can be found.
In this article we want to explain the ins and outs of hydraulic powerpacks. A vital piece of equipment that is used with so many machines we see every day.
In a nutshell, hydraulic powerpacks are self contained units that are used instead of a built in power supply for hydraulic machinery. Hydraulic power uses fluid to transmit power from one location to another in order to run a machine. It really is as simple as that.
So what do they look like?
In order to recognise and better understand hydraulic powerpacks, it is a good idea to get to know the key components. Hydraulic powerpacks come in many different shapes and sizes, some are very large and stationary whereas others are much smaller and more compact. In fact, some hydraulic powerpacks are so compact that they can easily be transported in a small van or even an estate car.
The only real way to identify hydraulic powerpacks is through its main components. No matter the size of the unit, all power packs will have the following; a hydraulic reservoir, regulators, a pump, motor, pressure supply lines and relief lines.
What do these components do?
It may be obvious to some but in this post we wanted to explain every component as simply as possible. So here goes.
First up is the hydraulic reservoir which quite simply holds the fluid. Reservoirs will come in different sizes.
Then we have the regulators. Regulators are vital as they control and maintain the amount of pressure that the hydraulic powerpack delivers.
Thirdly we have the pressure supply lines and relief lines. The supply line simply supplies fluid under pressure to the pump and the relief lines relieve pressure between the pump and the valves. The relief lines also control the direction of flow through the system.
Finally we have the pump and a motor. We will begin with the simpler component of the two, the motor. The motor is simply there to power the pump. Easy as that. Now the pump generally performs two actions. Firstly, it operates as a vacuum at the pump inlet and through atmospheric pressure forces fluid from the reservoir into the inlet line and then to the pump. It then delivers the fluid to the pump outlet and pumps it into the hydraulic system. We did warn you that the second part would be slightly more confusing.
So what is the function of hydraulic powerpacks?
Hydraulic powerpacks deliver power through a control valve which in turn runs the machine it is connected to. Hydraulic powerpacks come with a variety of valve connections. This means that you can power a variety of machines by using the appropriate valves.
Hydraulic powerpacks are relied upon by a range of different machines that use hydraulic power to do its work. If a machine is required to carry out heavy or systematic lifting then its likely it would need help from a hydraulic powerpack.
To make it easier for you to understand, we have included a list of trades that regularly rely on our powerpacks. On a building site you will see machines like bulldozers and excavators, which both need hydraulic powerpacks. But, it is not just on building sites that you will find these types of machines. Fishermen and mechanics both need hydraulic powerpacks too. If we did not have them then how would fishermen lift their nets or how would mechanics lift our cars?
When picking a hydraulic powerpack there are a variety of pumps and options to pick from and it is important to pick the right pack to meet your machines needs. It is also important to consider a pack that will help maximise productivity and minimise cost.
Many people will overlook the necessity of hydraulic powerpacks, but they really are vital to ensuring our society runs efficiently.
Do you need to maintain hydraulic powerpacks?
Yes you do and this is hugely important! Hydraulic powerpacks require regular maintenance to ensure they are working properly and safely and to help extend their life. Maintaining hydraulic powerpacks is relatively simple and includes checking the tubing, this can be for any noticeable problems such as dents or cracks. It is also vital to regularly change the hydraulic fluid and look at the reservoir to check for any corrosion or rust.
What hydraulic powerpacks do we provide?
Generally we provide four different types of hydraulic powerpacks. You can pick from a standard powerpack, a mini powerpack, a micro powerpack or a bespoke powerpack.
The standard hydraulic powerpack uses a standard range of modular components and is ideal for the most demanding industrial applications. The mini powerpack is ideal for applications requiring up to 5.5kW. The micro hydraulic powerpacks were originally produced for mobility applications, so are great for when space is limited. Finally, if none of these seem to fit your needs then we offer bespoke hydraulic powerpacks ensuring your application gets the hydraulic powerpack it requires.
Finally, who is the genius behind hydraulic powerpacks?
The man behind hydraulics was Laissez Pascal. A French mathematician, physicist and religious philosopher who lived in the mid seventeenth century. Pascal made observations about fluid and pressure which led to Pascal’s law. Pascal's law states that when there is an increase in pressure at any point in a confined fluid, there is an equal increase at every other point in the container. Hydraulic powerpacks have been designed based on Pascal's law of physics, drawing their power from ratios of area and pressure.
So, interested in our Power Packs? Come on over to the main website and see what we can do for your Hydraulic Power Pack Needs .
If you’re curious about how hydraulic cylinders work, then you could find this post to be interesting. Let’s take a look at these powerful components that make it possible to move and lift the heaviest of items with ease.
You may not have ever considered this before, but what do you think deploys those huge wheels that aircraft need to land? They are put away tidily throughout a flight, and then when they’re approaching Heathrow, out they pop and all at the pilot’s press of a button.
Landing gear is operated through a hydraulic system. As with any hydraulic system, there are pipes, cylinders and of course hydraulic fluid. The fundamentals of this are the same as with any hydraulic system. When force is applied at one point, it is transmitted to another through the use of incompressible fluid.
Hydraulic cylinders mostly come in parallel pairs that are of differing diameters and are connected by a pipe. The cylinders will be at right angle to the pipe. This arrangement is then filled with a hydraulic fluid such as oil until the cylinders are partly filled.
The space that is left in the hydraulic cylinders will enable the pistons to operate. In one cylinder, the piston will be smaller than in the other. Fluid will be pushed into the chamber of the small piston and when force is applied, it will push the fluid into the chamber of the big piston as it will be incompressible fluid. This will then move the big piston. Due to the difference in size, the effect of the small piston’s movement will be multiplied. So for example if a small piston has a downward force applied to it of 100 lbs – the force on the big piston will be 900 lbs.
Hydraulic cylinders remove the need for a rigid structure when it comes to transferring force between two different points. This can be used to the hydraulic system’s designer’s benefit and a number of twists and turns can be added to the system. For example, there might be a space constraint. Using the different cylinders at different sizes, it’s possible to create a system that will pull, push or even lift heavy weights.
Although the hydraulic systems that are used in our everyday life are not built with cylinders quite as basic as what’s described above, they are fairly similar. Let’s look at the different components involved:
· Cylinder barrel
· Piston rod
· Cylinder bottom (Cap)
· Cylinder head
· Cylinder bottom connection
· Rod glands
There are two different main types of hydraulic cylinders used. The tie rod type of cylinders and the welded body type. The former are used when there is a need for heavy-duty industrial or commercial use. Some are small bore and others large bore. The welded body cylinder type has no steel rods in it. The top of the barrel of the cylinder is welded directly onto the object that is expected and designed to move. Although these cylinders are small in size, they are used in a surprisingly large number of different machines. In some cases it’s necessary to use a telescoping hydraulic cylinder where the piston rod will retract into the barrel of the cylinder.
Hydraulic power has really evolved over the last 50 years or so. Much of the progress has come from the aeronautical industry, surprisingly. Although hydraulics have been used since before the time of the first recorded history, it’s only now that they have really come of age and have made such a tremendous difference to us in so many fields.
Hydraulics has been around for a very long time. But are you aware of how far it has actually come? You wouldn’t be alone if you responded with no. It is a very technical subject that can be quite difficult to understand, but in this article we want to tell you the story of hydraulics! We want to share with you who discovered hydraulics, what it was originally used for and how hydraulic power got to where it is today.
So why don’t we start at the beginning! Where does the word hydraulic come from?
The word hydraulic originates from the Greek word ‘Hydros’ which means water. Why water? Well, this is because water was the first liquid to be used in the hydraulic system. Today, hydraulics includes the physical behaviour of all liquids, not just water.
There are a number of purposes for having hydraulic fluid inside a hydraulic system. Of course, its main purpose is to transfer force from the hydraulic power unit to an actuator. In addition it has to:
Without any of these functions, the entire hydraulic system would not work as well as it should. This leads us to the question of ‘what would prevent any of these functions from fully operating and how can we prevent that from occurring? The biggest threat to hydraulic fluid being compromised is from particles in the fluid.
Although particles may not affect the power of the machinery, the other functions can be compromised by having particles in the fluid. These particles can impact the surface tension of the fluid and encourage microscopic leaks that can become problematic. They can get caught between surfaces that would usually be lubricated. This friction can cause damage and it can also result in an increased temperature of the fluid, which can then go onto cause further damage.
The most effective way to combat particles in hydraulic fluid is to use good quality hydraulic filters that are changed regularly. By keeping the hydraulic filter optimally operational, it’s possible to minimize contamination by the particles, and keep down problems that can occur from it.
What Won’t the Hydraulic Filter Do?
Although hydraulic filters are good, they aren’t perfect. For example, they won’t stop water from getting into the system. If water does get in, it can cause all manner of issues.
However, it’s still wise to equip your system with the best hydraulic filters that you can – the result will be less maintenance and an increased lifespan for your machinery.
Although hydraulic cylinders are so incredibly simple, equipped with just a steel rod, an iron tube and a few other pieces holding everything together, they are remarkably powerful. They provide the workhorse brawn of our nation’s industrial works and are what makes it possible to rapidly move earth and other materials around us. In this post we look at how the hydraulic cylinder works.
It’s a basic lore that area x pounds per square inch (PSI) = Force. For example, if you put 1 pound of pressure onto a 1 inch object, you will have 1 pound of pressure. If you put 1 pound of pressure on 2 inches, you will have two pounds PSI and so on and so forth.
This means that the size of the piston is closely related to the power of pushing or lifting available.
Inside the cylinder, the fluid will push against the piston. The diameter of the piston is known as the bore. When it comes to powerful lifting, it’s the larger bore cylinders that can perform the best and will be employed by the larger applications that we see in use.
Inside the piston is the hydraulic fluid. It needs to be contained by a seal. If the seal is in anyway defective, it won’t be able to perform to its utmost capacity. Although you may not see any oil or fluid on the outside, the damaged piston seal will make it possible for the oil to bypass the piston. This will not result in ultimate pressure, and so the lifting will not reach the level of effectiveness that it should.
The shaft or rod of the cylinder is what travels through the head of the cylinder. It attaches the piston to the fitting at the end. The strength of the piston in combination with the diameter of it will be what determines whether it will bend. Pistons take a lot of stress and it will need to be strong enough to cope with the ‘side load’ that it will get from being extended.
When it comes to the total distance of travel between a fully retracted length and a fully extended length, this is known as the stroke.
The head or gland of the cylinder is the part through which the piston rod travels. Inside the gland, the piston rod seal has a weakness for leaking as it’s exposed to the elements ad it also collects debris.
The cap or butt of the cylinder is located at the base. In some cases, it does not require a seal as it is welded to the cylinder tube.
Hydraulic cylinders are wonderful inventions, and without them our world would not be what it is. For more on hydraulic systems, follow our blog regularly.
The front suspension of modern motorcycles is a set of telescopic tubes that absorb impact from the road by moving within each other. They are comprised of two parallel hydraulic cylinders that act as shock absorbers; the first appearance of hydraulics to provide a smooth damping action was in 1935, on a BMW machine. The hydraulic cylinders are attached at the top to the steering bars, and to the centre of the wheel at the bottom; so is connected to the frame at two points. The entire assembly is called the front forks. Within the hydraulic cylinders is a coil, which provides much of the suspension action, surrounded by oil. The coil is under constant compression. The compression and lag are set according to pre-load settings when the machine is first sold, which allows the motorcycle to be ridden by almost any rider and in any style. Fine adjustments can be made to the tuning of the forks within the range where the internal coil is still under compression.
Motorcycle front forks come in two set ups, either the conventional type where the bottom portion of the fork assembly slides up over the fork tubes, or “upside down” (USD) forks, where it is the top portion that moves; the fork tubes are fixed at the bottom. There are benefits to both systems, but the USD forks are stiffer and give better handling at speed, so are often used on race bikes. They are more expensive than conventional forks but the benefits of better track handling make them the first choice for competitive riding. Race forks are also often manufactured with a built in coolant reservoir, which helps keep the oil cool under race conditions.
The oil used in the forks is different to the sort of oil used in the engine; the viscosity makes a big difference in the performance of the hydraulic forks and therefore the ride handling. Different riding conditions also affect the oil, as it becomes less viscous as the temperature increases. For this reason, a hydraulic fork oil of 5w may perform well and give responsive handling under normal road riding conditions, but used in the forks of a race bike it will heat up too quickly and perform badly; as it heats the suspension will become less responsive and feel spongy, so cornering will be affected negatively.
Road riding does not generate the same heat in the engine and body of the motorcycle as track racing, so although an oil of 10w to 12.5w may be used in the USD forks of a track bike, this weight would be very hard and unresponsive when used in a motorcycle that is used for commuting. The weight of the rider is a factor to consider when choosing the appropriate weight for a hydraulic oil, as heavier riders generate more downwards force on the forks and therefore require an oil of higher viscosity to give the same resulting performance. The speed at which the motorcycle travels when in a race situation also increases the downward force on the suspension; the higher the speed the more pressure is exerted.
Hydraulic shock absorbers are also found in the rear suspension of the motorcycle, but unlike the front suspension, which has a small range of setting adjustments, the rear hydraulic shock system has many more settings that can be adjusted. The coil is also usually external to the hydraulic component, instead of housed inside the fork assembly. Also unlike the front forks, the rear shocks do not take the brunt of the impact and force of the road, so are less likely to make a big difference to the comfort of the ride. When taking a pillion passenger, however, it is vital to adjust the rear hydraulic suspension to accommodate the extra weight over the back wheel. The front fork settings are not affected as much by the extra weight and can be left alone unless the passenger is exceptionally heavy.
Hydraulic Power Pack
Connect with us
Connect with us on social media or eBay