Compact and Powerful Hydraulic Actuators

As the name suggests, the hydraulic power unit, based on Pascal’s law of dynamics is the main driving component in a hydraulic system. It consists of a motor, a reservoir and a hydraulic pump. Their synchronised action even in a mini hydraulic power unit generates ample power to stir up motion and drive the hydraulic ram. This space saving vertical style device is designed for quiet and leak-free operation.

These power units generate power as per the pressure exerted on a specific area. With a wide range of applications, these are designed depending on the ultimate utility and manufactured. To illustrate this aspect, the Delhi NCR based Dantal Hydraulics is one of the leading Indian companies engaged in the development and fabrication of such silent and leak-free operation power units. Apart from customised applications, the Mini Compact Power Packs produced by this company are extensively used in systems like – Read more

Amazing Action of Hydraulic Cylinders

This is a true story of an inquisitive journalist. Watching an off-shore rig of Oil and Natural Gas Commission (ONGC) on the Bombay High during early 1980s from a helicopter or aboard an OSV (off-shore supply vessel) was a delight for him. He would grab every opportunity of visiting Sagar Samrat and another rig as and when the occasion arose for coverage in the magazine for which he was the correspondent in Bombay.

He used to wonder as to how such an expansive platform was hoisted and placed on the mammoth jacked up rigs in the middle of the sea with the anchor winches operating round the clock by turns. And then came the day in late 1982 when a gigantic rig assembled at the Robin Shipyard in Singapore was towed and tugged by several barges to Bombay.

All this while, this journo’s inquisitiveness grew with each passing day and after covering the event of formal induction of this new rig from Singapore, he sought an exclusive visit by an OSV to watch its commissioning that was to take place a fortnight later. Three weeks later, he was thrilled to receive a telephonic call from the PR Manager as well as an invitation from the Director of Engineering to watch the commissioning of the new rig. Read more

Hydraulic Applications in All Walks of Life

Applications of hydraulic and pneumatic engineering have literally revolutionised the industrial scenario. So much so, right from the day-one when the utility of French scientist Blaise Pascal’s theory was given a try in mid-1660s and a century later the British innovator Joseph Barmah conceptualised his innovation of press, hydraulic solutions have streamlined the process of almost all the products and services. And today, this science of fluid-based dynamics can be witnessed or experienced in every other activity around us. Be it on the ground, up in the sky or over the river and sea including underwater, there is an application of hydraulic technology in operation.

Over the past couple of centuries, the never-ending study and research in this stream of engineering have resulted in the development of thousands of concepts and products to facilitate the functioning of a system based on hydraulics. One of them is the electro hydraulic actuator. EHA in short, it is a fully self contained actuation system that is energised by an electric source and transforms an input command signal into motion. It has been extensively used for the operation of wide range of systems.

The EHA is widely used in the following arenas among others: Read more

Thrust of Cylinders in Hydraulic Engineering

Hydraulic technology has ushered the ‘minimum effort, maximum result’ concept in almost every other industrial activity. A ready example is excavation of earth for basement at the construction site of a building. In contrast to the manpower and man-hours spent in executing this task that would have prolonged for over ten days at a stretch, a hydraulically operated excavator does the same job in a single day.

The key element in a hydraulic system is the cylinder, the mechanical actuator, aptly referred as hydraulic motor. There are two versions. Single acting hydraulic cylinders which are simple in design as well as economical and the double acting cylinders. While the single action cylinders function with fluid on only one side of the piston, the latter have a port at each end that are lubricated and supplied with hydraulic fluid for both the retraction and extension action.

By and large, the single action cylinders are found in almost all the steam and petrol or diesel driven IC (internal combustion) engines and also steam turbines, pumps, presses and ramps. The following are the main parts of a cylinder and these are designed and manufactured with utmost precision in which specifications could be as minute as 4 to 16 of a microinch: Read more

Versatile and Vital Power Devices

Almost the entire range of machinery and thousands of other systems or appliances function on account of linear actuators incorporated in their design. It is the actuator that generates motion and lends momentum to an engineered system. Depending on the application such as whether it should be rotary, pull, push, lift, hoist, drop, telescopic or to and fro, the actuator is designed and manufactured. The power source in it also varies such as manual, electric, air pressure, hydraulic, pneumatic, piezoelectric or ultrasound among others.

In the design, an actuator for standard systems usually has the motor as a separate cylinder attached to its side, either parallel or perpendicular. The motor is attached to the end of the actuator for energising the system. Compact actuators have specially designed motors that try to fit the motor and actuator into the smallest possible shape.

The actuators provide a safe, quiet and clean movement with accurate and regulated motion. They are energy efficient and have a long lifetime with little or no maintenance. Incorporating an actuator is very easy as compared to other energisers such as hydraulic systems. Space wise, it takes least possible space since there is no involvement of pumps or hoses in the system. Apt functioning of a system or a product depends on the actuators adaptability to a wide range of specific of applications. Read more

Energising with Compact Power Packs

The advantages of hydraulic engineering and pneumatic technologies have been multi-fold with thousands of applications in mega, medium and light industries. A relevant appliance is energised to function for which a mini compact power pack also known as DC power unit is in-built or integrated with the systems. A DC power pack supplies a voltage of fixed polarity (either positive or negative) to its load. Depending on its design, a DC power supply may be powered from a DC source or from an AC source like the power mains. These units that supply regulated and controlled power are meticulously designed, developed and manufactured. Several aspects such as safety, quality standards and also energy efficiency are kept in view during manufacture. Often these are also customised.

For instance, among the DC power unit manufacturers in India, the Delhi NCR-based Dantal Hydraulics has facilities for the entire range power units for numerous applications. It also makes AC/DC Mini Power Units. Some of them are:

  • Dock leveller
  • Electrical Stackers
  • Emergency lowering
  • Car Carrier
  • Tier Changer
  • Car Lift
  • Scissor Lift
  • Car Parking Systems
  • Scooter and three wheeler Lift
  • Customised Applications

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Compact Energy Saving Actuator

In modern engineering, hydraulic power has given an impetus to the operation of various applications. Developments in this technology such as the concept of electro hydraulic actuator, EHA in short have further revolutionised the entire operation. Earlier hydraulic systems were energised by pumps which in turn called for tubing and allied parts. It was also observed that in the absence of safety in the design, the functioning of a pump was prone to hazards. Fortunately, the EHA has eclipsed these short comings and also improved the overall performance of hydraulic powered systems.

Primarily, the EHA was designed for applications in aviation particularly in a pilot controlling the aircraft’s speed and ailerons when airborne as well as on the ground. With drastic advancements witnessed in the size, capacity and speed of an aircraft, hydraulic engineers rose to the occasion and developed the electro actuator. In the principle on which EHA functions, motors with enhanced power drive a reversible pump that is linked to the hydraulic cylinder that renders the ultimate action.

This compact integrated system which includes the pump, the cylinder and a reservoir of hydraulic fluid, is packaged into a single self-contained unit. Initially, an EHA was made operational by modulated electrical pulses such as ‘fly-by-the-wire’ systems in aviation which have been replaced by the optics technology. Thus today, it is ‘fly-by-light’ concept. In addition to the lightweight, the EHA is instrumental in saving energy to a great extent. It draws power only when moved and the pressure is regulated internally when the motor stops.

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Air handling in hydraulic system

Over the last 50 years there has been a surge in using aircraft hydraulic systems. The biggest challenge has been managing the air as it moves in the circuit while steering the aircraft. It is to have an effective approach of managing the air pressure as any deviation may cause bizarre and untoward occurrences. Therefore it is important to know the ideal ways to handle the air in Hydraulic Fluid.

 Many symptoms of aerated hydraulics have plagued the aerospace industry. Before you strike out the symptoms typical to aerated systems, it is equally essential to know how and why the fluid becomes aerated. Aeration is caused due to the accumulation air bubbles in the chambers of the system wall. The saturation of the system fluid leads to pressure on the built-in chambers. Use of separators to make sufficient compartments helps keeping the fluid/oil de-aerated.

Various air extraction techniques are not much effective in the case of aircraft system as it face a lot of pressure. Consequent to myriad research and studies, a laboratory model of air-oil came into existence. There are many techniques that include the process air handling in an effective manner. The air-oil separator functions on the logic of pacifying the pressure inside the chamber that contains the hydraulic fluid which is directed from the pressurized system.

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Components & Specifications of Hydraulic Cylinder

What are hydraulic cylinders?

A hydraulics cylinder is a mechanical actuator that generates force created by a compressed liquid locked in a cylindrical vessel. They are a variety of application of such cylinders as these are used in manufacturing machines, construction machines and garbage dump trucks. The fluid of these cylinders is an oil-based lubricant to facilitate the back and forth movement of the barrel. The barrel exerts pressure on the fluid generating force that is ten times greater than the force exerted on the fluid.

What are the different parts and variants of hydraulic cylinders?

A standard hydraulic cylinder can be broadly divided into three parts. First is the barrel itself, second is the base or the cap and lastly the end of the cylinder. The role of barrel is to keep the pressure of the cylinder intact. The further classification of the parts may be listed as piston, piston rod, and seal gland. The role of Piston is to maintain the back and forth movement inside the barrel, it also varies the pressure inside the barrel. The piston rod is a hard piece of chrome attached to the piston that is connected with the cylinder adjoining the end of the rod.

The seal gland is prefixed at the top of the cylinder and prevents leakage of the compressed oil keeping the pressure of the barrel as it is. A mini hydraulic power unit will include all these basic parts. Different types of cylinders employ the type of parts with different operating pressure. On the basis of the components and its specifications, the hydraulic cylinder is classified as Multistage, Telescopic, Ram and cable cylinders.

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Multiple Utilities of Hydraulic Cylinders

Thanks to the great strides in research and development of dynamics over the last three centuries, remarkable applications have been witnessed in every sphere. One of them is the technology of hydraulics that is based on fluid dynamics. Rightly it could be termed as the mankind’s greatest invention of time-saving concepts. Hydraulics engineering has streamlined and simplified management of logistics. Evident are the assorted material handling systems like earth-moving machinery, winches and cranes, fork-lift trucks, jacks and lifts, compactors, loaders and dumpers etc. This technology has revolutionised the construction industry with products such as pile foundation hammers. Even hospital aids have found suitable applications of hydraulics.

All these above cited utilities function with the aid mobile hydraulic cylinders. Based on the principle of hydrostatic energy, a hydraulic cylinder acts like a linear actuator. With the aid of levers and booms, the cylinders are controlled and used as the needs be. These range from lifting, moving, bending, tilting and arcing applications. These are extensively used in mobile machinery and systems of all types. The design and manufacture of hydraulic cylinders happen to be a very high precision technology in which the engineers focus on stroke length, speed and flow calculations to the utmost minute detail.

Leaders in this industry like Dantal Hydraulics rely on 3D design for perfection in the product. Apart from being OEM for numerous systems, these companies also manufacture standard as well as custom-made special hydraulic cylinders.

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