Hydraulic Pumps in the Digital Age
How Hydraulic Pumps and Valves Have Become Part of the Digital Age
Have you ever taken the time to think how much harder your work would be without the help of hydraulic pumps and valves? Without hydraulics, you would have to perform many tasks by hand or manually. Imagine lifting a two-ton object manually using a series of pulleys or having to dig a hole using just a shovel!
Fortunately, thanks to hydraulic pumps and systems you do not have to worry about accomplishing such tasks. Several hundred years ago, things were very different prior to the invention of modern hydraulics.
A Brief History of Hydraulic Pumps and Systems
The use of hydraulics can be traced back to the ancient civilizations of Greece, Persia, China, Rome, and Sri Lanka. These early civilizations were inspired by the early uses of water power by the Egyptians. While most of their inventions used water hydraulics, they still helped fuel the advances made in fluid power during the 1600s to late 1800s.1
One of the most important people to help advance hydraulics was Blaise Pascal. He studied and developed several principles related to hydraulic fluids. These principles are what helped him develop his theory about the transmission of pressure in hydraulics, which we know today as Pascal’s Law.2
These developments and advances were later used by Daniel Bernoulli and his study of fluid dynamics. His research resulted in the creation of what we know as Bernoulli’s Principle. While Bernoulli was the one who figured out that as flow speed increases, pressure decreases, it was Leonhard Euler who refined Bernoulli’s efforts and created the Bernoulli’s equation in 1752 that we still use today.3
Bernoulli’s and Euler’s contributions further paved the way for another inventor, Joseph Bramah. Bramah invented the hydraulic press. It relied on Pascal’s Law, that the pressure of a closed fluid system remains constant. It also applied Bernoulli’s Principal.
Bramah created his first hydraulic press using two hydraulic cylinders of different diameters and set them up in a closed hydraulic system. He theorized that, as pressure was applied to the smaller diameter piston, the force it generated would be transferred to the larger diameter piston giving a greater force on the end of the larger diameter piston than required to push in the smaller diameter one. In 1795, Bramah obtained a patent for his hydraulic press.4
Another contributor to the advancement of hydraulics was William Armstrong. He invented the first hydraulic accumulators in 1846. Initially, the first accumulator was just a raised water tower that supplied the necessary pressure to hydraulic cranes. While this setup worked well in certain areas, it was not possible to use it at New Holland.5
The ground where the New Holland project was taking place consisted mostly of soft soil and sand, so the heavy water towers could not be constructed and used to power the hydraulic cranes. Armstrong developed a solution to his problem with the invention of the weighted hydraulic accumulator.
The weighted accumulator consisted of a cylinder with a plunger and a heavy weight. As the plunger moved upward, it drew water into the cylinder. Then, during the downward motion, the weight was used to increase the pressure of the water as it was pushed out of the cylinder.6
The inventions and advances during this time can still be found used in a variety of hydraulic pumps and valves, motors, and hydraulic systems today. For instance, the modern workshop presses uses the same type of configuration as Bramah’s press did over two centuries ago!
How Hydraulic Systems Continued to Evolve
During the late 1800s and early 1900s, there were advances being made in the creation of motor-powered vehicles and agricultural and construction equipment. In addition, enormous advances were being made in manufacturing and the types of machines being used to mass produce all sorts of products.
Many of the advances made during this time started to incorporate hydraulic systems in some manner. For instance, in farm tractors, the use of hydraulics made it easier to raise and lower attachments, as well as control the depth of ploughs.
During the last hundred years or so, two specific types of hydraulic pump systems evolved—the hydraulic piston pump and the hydraulic gear pump. Both types are well-suited to a variety of uses and function from simple hydraulic systems to very detailed and complex systems that require precision control.
Hydraulic gear pumps are generally used more often because they provide several benefits over piston pumps:
- Ease of Use
- Low Cost
- Delivery of a Constant Fixed Displacement
- Easily Adaptable
- Easily Customizable
The last two benefits make it possible to adapt a gear pump to fit the user’s configuration, equipment, and operating environment. In addition, valve control devices can be incorporated into the system design. Adding valve control devices makes it possible to mimic some of the features found in piston pumps but without the added cost.
Hydraulic piston pumps, on the other hand, are better suited to applications where greater operating pressure is needed. Often, gear pumps are not capable of producing the necessary operating pressure, so the system must be designed using piston pumps. Furthermore, piston pumps can be used in systems requiring a variable flow rate, as well as in systems with torque and power limitations.
Who Invented Digital Hydraulics?
In 1999, Matti Linjama from the Tampere University of Technology developed the concept for digital hydraulics. He theorized that computer-controlled digital valves could be used in place of current hydraulic valves to achieve the same desired output while, at the same time, reduce the overall number of valves in the system.7
Even though it took about a decade before any real advances were made, working digital hydraulic systems started to be produced in 2009. These first digital systems were built to address system inefficiencies found in modern hydraulic manufacturing equipment.
It was not long before other industries took notice, including the automotive industry. Today, you can find digital hydraulic systems used for anti-lock brakes, stability control systems, and various driver-assisted features like emergency braking and variable cruise control.
Other industries which have started to benefit from digital hydraulics include:
- Bulk Paper and Pulp
- Printing Press/Printed Media
- Clothing and Apparel
- Renewable Energy
One advancement made using digital hydraulics was the invention of Digital Displacement® Technology.
How Digital Hydraulics Helped Create Digital Displacement® Technology
In 1994, Edinburgh Wave Power Group created a company called Artemis Intelligent Power. The primary purpose of this new company was to further the development of hydraulics by creating advanced systems and machines. Around the same time as Matti Linjama was developing digital hydraulics, Artemis Intelligent Power was working on the concept of Digital Displacement® Technology.
What this technology theorized is that it could be possible to enable and disable moving cylinders in real-time, using computer technologies and ultra-fast control valves, along with hydraulic pumps, which could be used to pump in fluid or remove it from specific manifolds.
Artemis’ theory is now a reality. There are “smart” hydraulic engines now available that do exactly what Artemis initially believed possible. Their invention improves the efficiency of hydraulic engines and makes it possible to do things conventional hydraulic engines have not been able to do.
Initially, the new engines were being developed for use in the renewable energy sector. While they have been successful in that particular industry, the lightweight and highly efficient engines started to be evaluated for other useful applications.8
Among the more recent uses of Digital Displacement® Technology and hydraulic engines include:
- Improving the fuel efficiency of public transportation buses
- Advancing the development of the “self-driving” autonomous vehicle
- Improving the operational efficiencies of aircraft
- Being adapted for use in excavators and large-scale construction, agricultural, and commercial machines and equipment
This is just a small sampling of the numerous and potential uses for digital hydraulics and Digital Displacement® Technology.
The Future of Hydraulics in the Digital Age
The future of hydraulic systems in the digital age look very favorable. The recent inventions and advances in the field could even make traditional hydraulic pump systems and engines obsolete in the not-so-distant future.
Part of the reason digital hydraulics are expected to continue to grow and expand are the numerous benefits gained by using digital pumps, valves, and systems, which include:
- Digital hydraulic systems are computerized, which means they can perform functions much faster than manually controlled systems.
- Digital hydraulics are more energy efficient than traditional systems without a loss of power.
- Digital hydraulics are more reliable than conventional systems. They require less maintenance, and systems can continue to be operated even when a digital valve has failed, which translates to less system downtime.
- Digital engines produce fewer emissions because they require less of them to operate. Additionally, fuel efficiencies are increased.
- Digital systems provide improved operational efficiency because they are computer controlled, which increases overall system precision. Digital systems also improve machine performance and output as a result of better precision.
- Digital hydraulic pumps and valves, engines, and related components can cost less to manufacture and produce. As a result, the overall costs for implementing a digital system solution can be less, compared to a conventional system.
As one might imagine, the latest advances in digital hydraulics are starting to grow and advance into new industries every day.
In addition, as the use of digital systems becomes more commonplace, the costs for pumps, valves, and other parts and components are expected to continue to decrease. This will allow other industries, where costs can be a barrier to entry, to start considering what applications and functions could benefit from digital hydraulic solutions.
Whether you are still using conventional hydraulic systems or are interested in moving to digital solutions, White House Products, Ltd. is here to help. We provide access to one of the largest inventories of hydraulic gear pumps, piston pumps, motors, valves, and related components, as well as the latest digital hydraulic technologies.
We can also help you custom design and build a hydraulic system solution to fit your specific needs and requirements. For further assistance in sourcing the right hydraulic pumps and valves, motors, and more, please feel free to contact us directly at +44 (0) 1475 742500 today!
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