Hydraulic jack: 10 best, device, principle of operation

A hydraulic jack allows car owners to quickly and safely change a damaged wheel on their car.
To do this, every car must have a jack, since the need to replace a wheel can arise at any time and anywhere on the road. Hydraulic jacks vary in load capacity, weight, dimensions, design, pick-up height and lifting height. In this article we will consider in detail the structure, operating principle, and technical characteristics of hydraulic jacks. Here are the most popular models by load capacity.

Purpose of a hydraulic jack

The main purpose of a jack is to lift and secure a heavy load to a small height. A hydraulic jack uses an incompressible fluid that is forced into a hydraulic cylinder using a hydraulic pump. Oil is most often used as a working fluid. This design of the hydraulic jack allows it to work with very heavy loads.

Hydraulic jacks are not intended for moving loads or holding loads suspended for long periods of time. To do this, after lifting the load to the required height, it is necessary to install additional supports on which the load will be supported. Without such supports, you cannot work under a load to avoid injury.

Classification of jacks

• Mechanical - work from the application of human force (rotating a handle or pressing a lever).
• Hydraulic - work due to a hydraulic mechanism.
• Pneumatic - allow you to lift a load by filling a special cushion with air. Industrial models are equipped with a compressor, domestic ones are connected to the exhaust pipe and filled with vehicle exhaust gases.
• Electrohydraulic - connected to the electrical network, which drives the hydraulic pump.
• Electro-pneumatic - they are connected to electricity, for example to a car cigarette lighter, due to which air is pumped into the pillow.

Hydraulic jack device

The hydraulic jack consists of the following elements:

• Frame . The body is made of hardened steel and can be short or long. The housing contains a cylinder with a piston.
• The base of the body is the base on which the jack rests during operation.
• The catch is the uppermost part of the piston, which rests on the load being lifted. It is made of high-strength steel and has a corrugated surface to prevent the load from sliding. It is often equipped with a height-adjustable nozzle, which allows you to place a mechanical initial emphasis on the load without affecting the hydraulics.
• Pressure gauge . Allows you to monitor developing pressure.
• Reserve container in which the working fluid is located. Using a lever system, liquid is forced from the reserve tank into the discharge cylinder, and then into the main one.

• Working fluid . Most often, special hydraulic oils are used as the working fluid in hydraulic cylinders. It is not recommended to fill the hydraulic cylinders with water or brake fluid, as they will cause corrosion of the internal metal elements, which will lead to rapid failure of the jack.
• Oil filter . Needed to clean oil from contamination.
• Main cylinder with plunger. The rise of the plunger is due to the flow of working fluid into the cylinder, the lowering of the plunger occurs when the fluid flows into the reserve tank.
• Discharge cylinder with plunger . Pumps oil into the main working cylinder.
• Inflation valve. Allows fluid to flow from the discharge cylinder into the main cylinder and blocks its reverse movement. That is, it is responsible for the movement of the working fluid in only one direction, preventing its return.
• Pressure relief valve (bypass valve) . After reaching the desired height, the jack must be returned to its original state. To do this, there is a valve that allows the oil to return to the reserve tank and relieve pressure. This valve is needed to drain excess fluid and prevent the jack from being overloaded.

Characteristics of hydraulic jack

Material

Hydraulic jacks designed for light weight are usually made of aluminum. More serious models, capable of lifting extra-heavy loads, are made of hardened steel or cast iron. The greater the load capacity the jack is designed for, the thicker the metal used in its manufacture.

Dimensions, weight and lifting capacity of hydraulic jack

All three of these indicators are directly related to each other. Jacks with high lifting capacity are large in size. And accordingly, a large unit has a lot of weight.

Small hydraulic jacks used for passenger cars are small in size, light in weight and have low lifting capacity. Bottle jacks with a lifting capacity of 2 tons have a height of 15-18 cm and a weight of 2-3 kg.

Serious jacks used for trucks, in construction and industry, have a large load capacity - up to 100-200 tons and are large in size and weight. Thus, bottle jacks with a lifting capacity of 200 tons have a height of 40-50 cm and a weight of 130-135 kg.

Limit load capacity

Indicates the maximum weight that the jack can lift. When choosing a jack for a car, you need to add 150-200 kg to the “curb weight” value indicated in the PTS.

Jack lifting height

The lifting height of a jack is the maximum possible height to which a load can be raised. This value consists of two indicators:

• pick-up height
  - the smallest distance from the support surface from which the jack can operate;
• The stroke of the rod (the stroke of the jack)
  is the maximum distance between the highest and lowest positions of the piston.

For most hydraulic jacks, this figure is 30-50 cm. While a mechanical rack and pinion jack can lift a load to a height of 1 meter.

Pickup height

A very important indicator of a specific jack model. Shows the minimum distance from the support to the lifted load (from the ground to the bottom of the car). May vary between models from 6 to 30 cm. A jack with a high lifting height will not be able to be placed under the machine.

Pad diameter

The diameter of the platform is the size of the support platform for resting on the load. Determines the stability of the stop and distributes pressure on the jack to the load. The larger the platform, the greater the stability and optimal pressure applied.

Principle of operation

The operation of the described jack is carried out by folding and unfolding a structure that looks like a diamond. As the horizontal corners of a rhombus contract, its vertical corners begin to move away from each other. Thus, the jack operates independently of the screw drive. A similar design of jacks can be equipped with different methods of screw drive:

• manual;
• electric;
• hydraulic.

A manual car jack is the simplest and most common of all. Everyone has seen it at least once. But a diamond-shaped specimen with an electric drive can not be found so often. Its device is even simpler than the manual version. You need to place it under the car in the right place and insert the connector into the cigarette lighter. Further, the ascent and descent control is controlled using the control panel. An electric jack of this type cannot be called a necessity; rather, it is a nice addition that may not always be convenient to carry with you for years.

A hydraulically driven device is extremely rare. The reason for this is its high price and operating features. In fact, this is a hybrid of 2 types of jacks (bottle and diamond-shaped). There is an oil pump on the housing that pumps fluid into the working cylinder.

Operating principle of a hydraulic jack

The operation of a hydraulic jack is based on the constancy of fluid pressure in communicating vessels. Inside the jack there are two “vessels” connected to each other. One vessel is the main cylinder with a working plunger, the other is a cylinder with a discharge plunger. This hydraulic system is filled with technical oil.

The injection cylinder is connected to an oil reserve tank and a lever. When the lever is pressed, the injection plunger moves: it lowers and pushes the oil out of the injection cylinder. The oil passes into the main cylinder and pushes the working plunger upward, due to this the load located on the jack’s support platform is lifted.

As a result of each press of the lever, a certain volume of oil is pumped into the main cylinder, equal to the volume of the injection cylinder. The discharge cylinder is filled with oil from the reservoir. Since pressing the lever alone is not enough to lift the load, they usually continue to move the lever until the desired height is reached.

Between the discharge and main cylinders there is a valve that allows fluid to flow in only one direction and prevents it from returning back to the discharge cylinder. The walls of the main cylinder must be designed for the weight of the load being lifted.

After reaching the desired lifting height, the jack must be returned to its initial position; to do this, it is necessary to open the bypass valve. The oil from the main working cylinder will return to the oil reserve tank and the jack will lower.

Advantages and disadvantages of hydraulic jacks

Hydraulic jacks have their pros and cons, which you need to pay attention to when choosing a jack for your car. When buying a car jack, you usually choose between mechanical and hydraulic jacks.

pros

• They have a high load capacity: 2-200 tons.
• A slight effort is required to lift the machine: pressing the lever to pump oil into the main cylinder. At the same time, human energy consumption is minimal, and the rise is fast.
• They have a very high efficiency - at the level of 80%.
• They can operate at sub-zero temperatures, since the oil in the cylinder does not freeze.
• They ensure smooth lifting of the machine, as oil gradually enters the cylinder, the rod rises without jerking.
• Smooth lowering prevents loads from falling and reduces the risk of injury when operating bottle jacks.
• They are highly stable thanks to the wide sole, which provides reliable support.
• Can be placed under any point on the body, since there is no rotating handle.
• There is a very small chance that the car will fall off the support.

Minuses

• They require periodic maintenance, monitoring the oil level, tightness of gaskets and valves, and oil changes.
• They require storage and transportation only in a vertical position, since oil may leak out when turned over.
• They are large in size and weight.
• An even support area is needed.
• The lifting height is greater than that of mechanical jacks, so hydraulic jacks are not suitable for vehicles with low ground clearance.
• The machine cannot be lowered to the specified height.
• They cost more than mechanical ones.

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Since ancient times, people have been faced with the problems of lifting large loads to a height; for this, many people were usually involved, and bulky structures were erected, which were not always super-strength, and therefore often broke, causing casualties. A way out of the situation appeared with the invention of a machine such as a hydraulic jack, which is still widely used today. Such an installation, unlike winches, is more reliable and is capable of lifting large loads at lower costs.

Purpose of a hydraulic jack

Today it is impossible to imagine carrying out repair work on a car, be it suspension repair or changing a wheel, without the use of jacks - special mechanisms that are designed to lift a heavy load and fix it at the required height. The most effective are hydraulic jacks, where the working force is created using hydraulic oil and a piston.

The first mechanical jacks appeared in ancient times. And the idea of ​​​​creating a hydraulic jack circuit specifically for a car arose unintentionally. Repairman Peter Lunati came across this idea in a hairdressing salon, being surprised at how easy it was for the hairdresser to fix the hydraulic chair at a certain height. In 1925, a complex platform lift with a hydraulic strut was made for a car.

Hydraulic jacks are distinguished by their lifting capacity, which ranges from one to several hundred tons, which allows them to be used in the repair of trucks and other heavy equipment. Machine bodies or flooring, foundation slabs and columns are used as loads. Depending on the purpose of use, such equipment has different dimensions and designs.

A hydraulic jack is used to move, lift and secure loads. The device is used in the field of general mechanics and tire fitting work, and is also indispensable when preparing a car for a long trip to create balancing: the wheel is removed using a jack and balanced using special equipment.

Modern hydraulic jacks are widely used not only in service stations and car repair shops. They are successfully used in oil refineries, power plants and other industrial complexes. The highest level of performance and ease of operation have allowed this technology to be introduced into the domestic environment, which is why many owners have a hydraulic jack in their garage.

This equipment is capable of operating in horizontal and vertical planes, so it is widely used at the construction site and for tensioning reinforced concrete structures.

Hydraulic jack design

The main load-bearing elements of a hydraulic jack are the body, the working fluid, usually oil, and the retractable piston. The hydraulic jack has an elongated or short body that is made of hardened steel. The housing performs the following functions: it acts as a guide cylinder for the piston and serves as a reservoir for working oil.

The screw with the lifting heel is screwed into the plunger, turning the screw out, so if necessary, it is possible to increase the maximum lifting height. This type of jack is equipped with a hydraulic pump with manual, foot or air drive. The hydraulic jack is equipped with safety valves and other devices to ensure long-term trouble-free operation.

The lifting mechanism and retractable hydraulic cylinder, raised upward by a special platform, are located in the housing holes. The descent occurs by turning the T-shaped handle. The equipment has polyamide wheels, which provide the jack with maneuverability. The body of the extended range is used mainly for working with buses and heavy vehicles.

Working principle of a hydraulic jack

Any hydraulic jack works on the principles of communicating vessels using liquid. Before work, you must place the jack on a flat, hard surface under the car and press the lever with the valve closed until the car rises to the required height. The vehicle is lowered by smoothly opening the device valve counterclockwise.

The working hydraulic oil is pumped by a drive pump using a lever. Liquid enters the cylinder through the valve and squeezes it out. The reverse flow of liquid will be prevented by valves - discharge and suction. To lower the jack back, you need to open the valve on the pump, then the oil will flow from the cylinder back into the pump.

The presence of threads on the body of the jack, which is protected by a dirt-proof casing, threads on the rod and threaded holes in the base, guarantees unlimited possibilities for the use and operation of hydraulic jacks for crimping, clamping and bending. A high-strength support, made of hardened steel and installed on the rod, can protect the hydraulic jack from damage. The corrugated surface of the support prevents loads from sliding. The force of hydraulic jacks is regulated by a built-in pressure gauge.

Advantages and disadvantages of hydraulic jacks

Hydraulic jacks are among the most unpretentious for all their power. An important feature of hydraulics is the incompressible working material. Hence the smoothness of lowering and lifting, fixing the load at the desired height and precise braking. Hydraulic jacks demonstrate a high level of efficiency - up to 80% and a significant load capacity - up to 200 tons with little effort due to the large gear ratio between the cross-sectional surfaces of the pump plunger and cylinder.

But hydraulic jacks have a much higher initial lifting height than mechanical models. Another difficulty is the impossibility of accurately adjusting the lowering height. To maintain the jack in working condition, it is necessary to constantly monitor the oil level and control the tightness of valves and seals. Such jacks can only be transported and stored in a vertical position, as otherwise the liquid may leak out of the tank.

The disadvantages of hydraulic jacks arise from their advantages. They are relatively slow - one cycle of pump operation corresponds to a not too high lift height. The disadvantages include the large weight and size, the high price of a hydraulic jack, as well as a small stroke for single-plunger models. In addition, these tools often experience more serious breakdowns and malfunctions than mechanical devices.

Classification of hydraulic jacks

There are several types of hydraulic jacks.

Bottle hydraulic jacks

The design of a bottle (vertical) hydraulic jack is the simplest. The scope of use of such jacks is quite wide due to the large range of lifted weights - from 2 to 100 tons. “Bottles” are used in trucks. In addition to the main advantages of a hydraulic jack, vertical models have several more - versatility of use, compactness and a large support area.

There are single-rod and double-rod bottle jacks. The hydraulic single-rod apparatus is characterized by its simple design and ease of operation, which expands the scope of its use and allows it to perform work of any complexity: installation and dismantling in mechanical engineering, construction, repair of cars, wheels of railway cars, use as a power unit of a press, pipe bender, pipe cutter and similar tools .

A telescopic double-rod jack has a similar design to a bottle-type jack; the operating principle of a bottle-type hydraulic jack is based on the use of several working rods. The piston is located at the base of the telescopic jack. It can be used in horizontal and vertical positions. It is compact and fits most cars. Lifting occurs using a lifting lever driven by a hydraulic cylinder.

Rolling jacks

A rolling jack works on a similar principle to a bottle jack, but with the difference that the axis of the working cylinder is not located in the vertical axis, moreover, the piston is not directly aligned with the pick-up and the lifting lever is activated. This device is called a rolling device because it is a cart on wheels that can roll on a flat surface. When the lifting arm and lever are raised, the jack “rolls up” or moves under the load.

Such a jack is driven by the same swing of the lever as bottle models, and is lowered in the same way - by turning the valve screw. If it is necessary to lower the load down, it is necessary to place the tubular handle on the valve screw, after which the partition will fit into the groove of this screw. By rotating the handle around its axis, the user rotates the screw accordingly, relieving the pressure in the working cylinder and lowering the load to the required height.

Most often, a rolling jack can be found at a tire service station, because it is ideal for lifting one side of the car and is quite quick to operate and install. The disadvantages of this design follow from the name - a rolling jack needs a flat, hard surface, concrete or asphalt, to work. In addition, the significant size and weight make it difficult to transport the unit in a car.

Rolling jacks are classified by purpose, as in the photo of hydraulic jacks:

• For personal use by motorists, with a carrying capacity of up to 3 tons;
• For car services and tire shops, with a lifting capacity of up to 4 tons and with pre-lift pedals to instantly achieve the required pick-up height;
• For servicing heavy machines and special vehicles (forklifts), with a lifting capacity of up to 20 tons and with pre-lift pedals and a sliding crossbeam, which is designed to lift one side of the machine.

Transmission rolling jacks are equipped with a special rotating frame. Here the smoothness and precision of hydraulic jacks is demonstrated in all its glory. The gearbox of a car that is being mounted or dismantled can be precisely fixed in a horizontal or vertical plane in the desired position.

Hydraulic hybrids

Two-level jacks are needed mainly in car repair shops, where they work with different cars. The features of this device include two lifting platforms. The drawing of a two-level hydraulic jack is generally a hybrid of a rolling jack and a bottle jack. To be more precise, a two-level jack is used at a height of 65 - 375 millimeters from the ground as a rolling jack and at a height of 375 - 687 millimeters as a telescopic one. When working with the lifting mechanism, use a hand lever and a foot pedal.

The pneumohydraulic jack combines hydraulics and pneumatics. It can be manufactured in a rolling solution and has a load capacity ranging from 2 to 80 tons. The initial pickup height is low. It is used exclusively as equipment for car service.

Hitch jacks

Low-lifting toe jacks are widely used wherever a low lifting height is needed: for installing and dismantling various equipment, for lifting rails on the railway, as well as in auto repair shops. It is precisely this low pick-up height, which ranges from 15 millimeters, with the possibility of step-by-step adjustment, that is very convenient when assembling mechanisms and acts as the hallmark of a hook jack. But this jack is based on a simple bottle-type device.

Diamond jacks

Hydraulic diamond jack is mainly required for lifting machines during repairs. It is characterized by high reliability when compared with its screw relative, and is practically not inferior to it in ease of use.

In a diamond jack, four levers act as load-bearing elements, which are connected by hinges. The operation of a hydraulic jack and lifting loads is based on changing the angles between the levers. The advantages of diamond jacks include their small dimensions, which provides convenient storage, transportation and, at the same time, a significant supporting surface and structural rigidity. Relatively low pick-up height.

Manufacturing of hydraulic press

When a car enthusiast independently services his entire vehicle fleet, one of the most necessary tools is a press. We suggest you make your own press from a hydraulic jack, which will become a reliable companion when performing a whole list of work. With its help, you can punch holes in different materials, press inserts and bushings, and press metalworking waste.

Assembling a hydraulic press is not that difficult. For this you will need a welding machine with the required number of welding electrodes, a hacksaw, an angle grinder with a metal disc, a thick-walled steel profile to construct the press. The functions of the power unit, which exerts the required operating pressure, are performed by a hydraulic jack.

The first unit of the hydraulic press is the support platform for the jack. Since the resulting pressure will be proportional to that applied to the base and upper working units, the strength of the base should be maximum. This can be achieved by making several stiffening ribs on the base. To make the base, take a steel square or rectangular profile that has a size of 40 by 50 or 50 by 50 millimeters and cut 4 parts about 250-300 millimeters long using the above tools.

After this, it is necessary to lay these parts with the side walls facing each other and weld the joining seams at the top and bottom to increase the rigidity of the base of the press. To ensure greater stability of the hydraulic jack, weld a steel plate to the resulting structure, the sheet of which has a thickness of 8 -12 millimeters and a size of 250 by 200 millimeters.

The next stage in the manufacture of a homemade press from a jack is the production of a stop and racks. To do this, you need to saw off 2 parts from a profiled thick-walled rectangular or square pipe of the required length. To calculate it, you need to clarify the maximum stroke of the rod using the instructions supplied with the jack and add the height of the hydraulic jack itself and the support platform to the resulting size.

Make the stop from the same material as the racks. The length of this part must be equal to the width of the support platform in order to maintain the overall geometry of the structure. Connect the stop and the resulting posts with a weld and weld the U-shaped structure to the base.

When performing such assembly operations, it is recommended to use a simple device that ensures the perpendicularity of the parts to be joined. On a steel sheet that is at least 10 millimeters thick, two pieces of steel corner 40 by 40 millimeters should be welded at an angle of 90 degrees. Place the parts to be connected later in this device and weld.

This way you can achieve the desired connection angle. For additional convenience, this improvised square is additionally equipped with clamping devices that fix the parts to be joined and prevent the connection angle from being violated due to thermal changes during welding in the metal.

The next mandatory element of our press is a removable stop that can move along the guides and transmit pressure from the central working rod of the hydraulic jack to the workpiece. To make it, prepare several pieces of steel strip, which is about 1 centimeter thick. Make the length of the parts less than the resulting distance between the posts. Connect the resulting parts in several places by welding on both sides.

To ensure quick replacement of this part when performing any hydraulic work and to fix the element when moving on vertical posts, it is necessary to drill two through holes in the resulting block of steel strips and saw off two plates; their length should be 100 millimeters longer than the length of the block. Also drill two holes in the plates that match the holes in the block.

When installing the block on the press frame using a hydraulic jack, select two bolts of the required length with nuts and washers with your own hands and connect the resulting plates to the block so that they are located on both sides of the racks. If there is a need to achieve less free play of the hydraulic jack piston, the space between the moving stop and the upper beam of the structure can be reduced by additionally installing an intermediate square profile.

To do this, saw off a section of a square profile that has a length that is equal to the distance between the posts, and attach it at an equal distance with the welds. This will significantly reduce the working distance of the hydraulic press and reduce the time spent on certain types of work.

To further reduce the stroke of the working rod of a hydraulic jack, you can use additional replaceable inserts, which are made of solid or hollow steel profiles or replaceable anvils. To create them, you should saw off several parts of different thicknesses and additionally mark them for quick and thorough selection of the desired element.

Hydraulic jack repair

Hydraulic jacks periodically require maintenance, so it is necessary to add liquid to the working cylinder, which flows out during operation through oil seals and various seals. In addition to oil leakage, malfunctions of the jack include jamming when lifting a load to a certain height, the inability to lower the jack after lifting, or the inability to lift even a light load.

Oil leak

To repair and test a hydraulic jack at home, you should buy the necessary repair kit for the equipment. Before performing repairs, you must first disassemble the device. An extension to the keys may be required to provide significant force and greater leverage. Be sure to prepare a container to drain the old oil and prepare new working fluid.

After this, the pistons should be removed and checked for corrosion. All dirt and corrosion are removed. Check to see if the stem is bent. If deformation occurs, then it is unlikely that it will be possible to make it even again and there is no need to repair anything further.

It is necessary to check the oil bypass valve. To do this, the valve is unscrewed and checked for deformation or dirt getting inside the valve. If the valve is faulty due to mechanical deformation, then it should simply be replaced. In addition, it can simply become dirty, and the ball will not fit tightly into its seat. This is the reason for the passage of working fluid.

Completely drain the old oil. This procedure is quite simple, although it takes a lot of time while the oil flows from one cylinder to another. The liquid is drained by pumping the system, moving the lever up and down. Wash all parts thoroughly to remove dirt and oil residues. Completely replace all cuffs and gaskets.

Another reason for the failure of a hydraulic jack may be dirt that has entered the working cavity. To remove it from there, you need to unscrew the head of the housing, pour kerosene into its base and pump the jack with the locking needle unscrewed. Upon completion of the operation, kerosene should be removed and clean oil should be poured into the working cavity.

Air entry

During long-term operation, air bubbles accumulate in the working cavity of the jack, significantly reducing its effectiveness. The reason for this is usually air that has entered the hydraulic system due to a lack of operating oil. You can fix this problem as follows.

First, open the oil tank cap and bypass valve, and then quickly pump the hydraulic press pump several times. In this way, air will be forced out of the working cavity into the oil container. You can then close the bypass valve and the hole leading to the oil tank. If you did everything correctly, the air will be removed and the jack will work normally again.

If your attempt is unsuccessful, repeat all of the above steps. However, this method is not the only one for removing air from the working cavity. It is not difficult to determine the presence of air in the working cavity: the jack does not work at all, or the load is lifted slowly.

First, unscrew the locking needle one and a half to two turns, then lift the plunger by hand by the screw to the uppermost point and release it so that it is again in the lower position. Repeat these steps twice or three times. To prevent a similar problem from arising in the future, it is worth periodically checking the oil level in the hydraulic jack and adding working fluid if it is insufficient.

Thus, you have become familiar with the design of a hydraulic jack, studied its advantages and disadvantages, understood the classification of such equipment and understood how a hydraulic jack works. Now you can start assembling the device yourself. And don’t forget about periodic maintenance and adding operating oil.

Application of hydraulic jacks

• Hydraulic jacks are widely used in professional car repair shops and tire shops, as well as by owners of jeeps and heavy SUVs. Passenger car owners most often prefer compact mechanical jacks.
• Due to their high load capacity, hydraulic bottle jacks are used in the repair of heavy cargo and agricultural equipment, and in industrial production for lifting super-heavy metal structures.
• In construction for lifting heavy blocks, parts of buildings, tensioning reinforcement using reinforced concrete.
• When laying oil and gas pipelines.
• When carrying out rescue operations and liquidation of consequences of accidents.

How does it work?

The operating principle of most lifts can be explained using hydraulic models as an example. Their functioning is based on Pascal's law and the principle of communicating vessels. At the same time, all existing models of mechanisms have a common property - the mandatory use of a lever (handle) in one form or another. The main distinguishing feature of most modern jacks is mobility

It is also important to consider the lack of assistive devices. Today, jacks are most often used in the following areas

• Construction. Lifting blocks and structural elements, as well as their fixation. Lifting systems for installing drywall and other sheet materials deserve special attention. There are also tension jacks designed for screwing joints under load with a certain force.
• When repairing vehicles of varying complexity - from replacing a wheel on the road, to performing more complex work in car service centers and tire shops.
• As a lifting device, if it is necessary to move and mount various large parts or equipment on supports.

Types of hydraulic jack

There are several types of hydraulic jacks, they differ in design.

Classification of hydraulic jacks

• Bottle.
  The simplest version of a hydraulic jack, the name comes from its appearance, which resembles a bottle. It has compact dimensions and a large support area. Allows you to work with heavy and very heavy loads: from 2 to 200 tons. Can be used when working with cars and trucks, special equipment, and for lifting houses in construction. It has a fairly high minimum lift, so it is not suitable for cars with a ground clearance of less than 200 mm. You need to work with a bottle jack on a perfectly level support.
• Rolling
  . There are several modifications for professional and household use. To work with them, you need a hard, even floor covering such as concrete, asphalt, or tiles. They are widely used in professional car repair shops for passenger cars.

• Telescopic.
  It has a telescopic piston, which allows you to increase the maximum lifting height.
• Double rod or double piston.
  Due to the two pistons in the design, it has an increased load capacity.
• Low toe hooks
  . Used in cases where a minimum pick-up height is required. Capable of lifting a load from a distance of 15 mm from the support, allowing step-by-step adjustment of the lift and securely fixing the load. They are used for raising railway tracks and in industry.
• Specialized:
  two-level, diamond-shaped.

Classification and comparative points

This issue should also be given attention, because it reveals the main differences between hydraulic and other similar devices. https://www.youtube.com/embed/rRJl6fK2qTs

Bottle devices

Jacks of this type have a fairly simple design. We can say that it is the most primitive among all the devices found today. Hydraulic bottle jacks are actively used in many areas of human activity, which can be explained by their high load capacity. With their help you can lift loads weighing from 2 to 100 tons.

Vertical versions have high strength characteristics and provide the possibility of using a wide support to perform certain operations. They are most widespread in the truck servicing industry, where they are used to lift trucks or buses.

Rolling mechanisms

This group of lifting mechanisms is also one of the most popular. Most often they are used in the automotive industry. In the design of these devices, the cylinder axis is not located in a vertical plane, but is connected directly to the jack lever. These devices are necessarily equipped with wheels that allow them to be moved on any surface.

Lifting mechanisms of this type are characterized by high load capacity. They are also very convenient to use. They work on the same principle as all other jacks. In terms of their design, rolling hydraulic jacks are almost no different from their bottle counterparts.

Hydraulic hybrids

These versions of jacks are most widespread in the field of car service, where they are used to carry out repair work of varying degrees of complexity and on a wide variety of cars. One of the features of these devices is the presence of two working platforms. They are useful when you need to lift a passenger car, and then some kind of gazelle.

This is an excellent choice for professionals. Such models combine the capabilities of a bottle jack and a rolling jack. Thanks to the fact that their capabilities could be embodied in one multifunctional device, buyers have the opportunity to purchase an indispensable assistant and save a lot on it. These devices are as easy to use as any other and can be operated using a hand lever or a foot pedal.

Hitch jacks

Most often, these mechanisms are used in cases where a small picking force is required. They are great for lifting any equipment. They can also be used in the process of assembling complex mechanisms, where a small pick-up height is required.

Diamond devices

Lifting mechanisms of this type are most in demand among car enthusiasts who need a device to lift their vehicle. These mechanisms are highly reliable. In their design, they look exactly like diamond-shaped screw jacks. Every car enthusiast will be happy to have such an assistant in the garage. In the design of these devices, four levers perform the functions of load-bearing elements.

Rating of the 10 best hydraulic bottle jacks

Hydraulic jack SPARTA 2t 50341 telescopic

Designed for lifting loads weighing up to 2 tons. The base of the jack is made of cast iron and has a protective anti-corrosion coating. Equipped with a safety valve that prevents lifting of loads weighing more than 2 tons. The weight of the lifted load should not exceed 2 tons.

Not intended for moving loads and maintaining the load suspended for a long time. After lifting the load, it is necessary to secure it with stands for support. If there are no supporting stands under the load, you cannot stand and carry out work. To work, it must be placed on a flat horizontal surface. The presence of a telescopic mechanism allows you to lift the load to a height of 410 mm without much physical effort.

The homeland of the SPARTA brand is Germany, assembly is carried out in factories in China and Taiwan, which allows you to combine German quality and low cost of production. SPARTA jacks are durable and inexpensive.

Technical characteristics of the jack SPARTA 50341:

• Load capacity - 2 t
• Pickup height - 170 mm
• Lifting height - 410 mm
• Case material: metal
• Type - double plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Weight - 3.2 kg
• Case - no

Hydraulic jack 2t Gigant HBJ-2

The hydraulic jack of the Russian brand Gigant is produced at factories in China and Russia. Manufactured according to GOST R 53822-2010. Designed to work with loads weighing up to 2 tons. The jack is not designed to hold a load for a long time. When working under load, it is necessary to use additional supports. The Gigant HBJ-2 jack is distinguished by reliable operation and good stability due to its large support area.

Technical characteristics of the Gigant HBJ-2 jack:

• Load capacity - 2 t
• Pickup height - 181 mm
• Lifting height - 345 mm
• Case material: metal
• Type - single plunger
• Telescopic mechanism - no
• Horizontal operation - no
• Weight - 2.6 kg
• Case - no

Hydraulic jack SPARTA Compact 3t 50332

The hydraulic jack SPARTA Compact 3t of the German brand SPARTA is assembled in factories in China. It has established itself as a reliable and inexpensive tool, thereby gaining great popularity among car enthusiasts. Designed for lifting loads in construction and during automotive repair work. It has a stable cast iron base, a body made of durable steel, and a polished rod that increases the service life of the jack.

It has a small pick-up height of 180 mm, which allows you to work with cars with low ground clearance. The maximum lifting height is 320 mm. After lifting the load to the required height, it is necessary to securely secure the load with supports to ensure the safety of the working person. It is impossible to work without additional supports. The jack is not designed to move a load and hold it suspended for a long time. The weight of the lifted load should not exceed 3 tons.

Technical characteristics of the jack SPARTA Compact 3t 50332:

• Load capacity - 3 t
• Pickup height - 180 mm
• Lifting height - 320 mm
• Case material - steel
• Type - single plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Retractable screw stroke - 50 mm
• Weight - 2.4 kg
• Case - no

Hydraulic jack BelAK 3t BAK.10040

The BelAK BAK.10040 hydraulic jack has a lifting capacity of 3 tons and is perfect for car repairs. It is produced under the BelAK brand, owned by the Russian production holding BelAvtoKomplekt. Assembly is carried out at two factories in China, where production meets international ISO standards, all products are manufactured in accordance with GOST and undergo final quality control.

The jack is supplied in a case, which makes its storage especially convenient. It has a wide support platform and two handles. Has a low lift of 145 mm. The BelAK BAK.10040 jack has a long service life, low price, and high quality.

Technical characteristics of the jack
BelAK 3t BAK.10040:

• Load capacity - 3 t
• Pickup height - 145 mm
• Lifting height - 285 mm
• Case material: metal
• Type - single plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Retractable screw stroke - 50 mm
• Base size - 85x70 mm
• Weight - 2.3 kg
• Case - yes

Hydraulic jack KRAFT 4t KT 800014

The KRAFT KT 800014 jack is designed for lifting loads weighing up to 4 tons, and is widely used in the repair and maintenance of vehicles. Belongs to the German brand KRAFT, which has been producing car parts and auto tools for more than 20 years. Assembly is carried out in China, where all products undergo mandatory quality control of international standards DIN, ANSI.

The jack has a safety valve that prevents lifting loads over 4 tons. Frost-resistant oil is used as a working fluid, which does not lose its properties at a temperature of -45°C. The convenient folding handle makes the jack compact. Supplied in a plastic case with a handle, which is convenient to store and transport.

Technical characteristics of the jack KRAFT 4t KT 800014

• Load capacity - 4 t
• Pickup height - 195 mm
• Lifting height - 380 mm
• Case material: metal
• Type - single plunger
• Telescopic mechanism - no
• Horizontal operation - no
• Retractable screw stroke - 60 mm
• Base size - 108x108 mm
• Weight - 3.6 kg
• Case - yes

Hydraulic jack MATRIX MASTER 4t 50754

Hydraulic jack of the German brand Matrix, assembly is carried out at factories in China and Taiwan. All manufactured products undergo strict quality control, which allows us to combine low price, high quality and long service life. Matrix Master 50754 has a load capacity of 4 tons, is made of durable anti-corrosion metal, resistant to rust and mechanical stress.

The jack has a wide base, which allows it to be used on fairly soft ground. Supplied complete with a plastic case with a handle. The case allows you to properly store and transport the jack - in a vertical position.

Technical characteristics of the jack MATRIX MASTER 4t 50754

• Load capacity - 4 t
• Pickup height - 194 mm
• Lifting height - 372 mm
• Case material - steel
• Type - single plunger
• Telescopic mechanism - no
• Horizontal operation - no
• Retractable screw stroke - 48 mm
• Weight - 3.9 kg
• Case - yes

Hydraulic jack SPARTA Compact 5 t 50333

The hydraulic jack SPARTA Compact 50333 is designed for lifting loads weighing no more than 5 tons. Produced in factories in China using German technology in compliance with all necessary requirements. The jack is distinguished by high build quality, durability and reliability. These characteristics, combined with a low price, make the SPARTA Compact 50333 jack an excellent purchase.

The jack is not designed to hold a load suspended for a long time; for this you need to use special supports, without which it is strictly prohibited to work under a raised load. The body is made of durable steel and has a stable cast iron base. The jack is equipped with a polished rod.

Technical characteristics of the jack SPARTA Compact 5 t 50333

• Load capacity - 5 t
• Pickup height - 180 mm
• Lifting height - 340 mm
• Case material - steel
• Type - single plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Retractable screw stroke - 50 mm
• Weight - 2.9 kg
• Case - no

Hydraulic jack BelAK 5t BAK.00042

Belongs to a Russian brand, assembly is carried out at a factory in China. Designed to lift cargo weighing no more than 5 tons. Despite its large load capacity, it has compact dimensions and, due to its low lift, allows it to work with machines with low ground clearance. The wide base ensures the stability of the jack and reduces pressing into the ground. If it is necessary to hold the load suspended for a long time, it is necessary to install additional supports, without which it is prohibited to work under the load.

Technical characteristics of the jack BelAK 5t BAK.00042

• Load capacity - 5 t
• Pickup height - 175 mm
• Lifting height - 345 mm
• Case material: metal
• Type - single plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Retractable screw stroke - 60 mm
• Working stroke - 110 mm
• Base size - 75x85 mm
• Weight - 2.9 kg
• Case - no

Hydraulic jack SOROKIN BottLine Jacks 12t 3.12

Designed to lift cargo weighing no more than 12 tons. The jack is of the famous Russian brand Sorokin, whose production facilities are located in China, Taiwan, Russia, and Europe. The jack is assembled in China, which reduces production costs and, accordingly, the final price while maintaining high quality products. It is used for construction, industrial and auto repair purposes.

Not designed to hold a load for long periods of time. After lifting the load to the required height, it is necessary to use additional fixing supports for safe work under the load.

The SOROKIN BottLine Jacks 12t hydraulic jack is easy to use and has a screw rod that makes it easier to place the jack under the supporting surface of the load. There is a metal handle on the side of the case, which is convenient for carrying the jack. At the bottom of the body there is a wide support base that prevents the jack from sinking into soft ground.

BottLine Jack® series bottle jacks are equipped with a telescopic mechanism that allows you to reduce the pick-up height while maintaining or increasing the lifting height compared to classic models.

Technical characteristics of the jack SOROKIN BottLine Jacks 12t 3.12

• Load capacity - 12 t
• Pickup height - 245 mm
• Lifting height - 570 mm
• Case material: metal
• Type - double plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Retractable screw stroke - 55 mm
• Working stroke - 270 mm
• Weight - 9.5 kg
• Case - no

Hydraulic jack WIEDERKRAFT 20t. WDK-81200

The WIEDERKRAFT WDK-81200 hydraulic jack is designed for lifting loads weighing up to 20 tons. It is used at service stations for freight transport, special vehicles and agricultural machinery. WIEDERKRAFT is a German brand; jacks are assembled in China. High quality is combined with long service life and reliability.

The jack has a handle, which makes it easy to transport. The wide base ensures the stability of the jack during operation. The screw platform is height adjustable.

Technical characteristics of the WIEDERKRAFT 20t jack. WDK-81200

• Load capacity - 20 t
• Pickup height - 226 mm
• Lifting height - 452 mm
• Case material: metal
• Type - single plunger
• Telescopic mechanism - yes
• Horizontal operation - no
• Retractable screw stroke - 150 mm
• Working stroke - 226 mm
• Base size - 144x150 mm
• Weight - 10.6 kg
• Case - no

Kinds

Today you can find telescopic jacks of various types on sale - from stationary to portable and mobile. In addition, the lifting device may differ in size, operating principle and design features. The most common types of two-rod jacks include:

Mechanical

Great for car enthusiasts. Its mechanism is driven by human physical efforts. Such a jack usually has a diamond shape and is produced with a sliding mechanism, the main component of which is a lead screw. To lift a load using a mechanical device, you need to twist the handle, and the load capacity directly depends on the screw thread (the wider the pitch, the higher the load can be lifted).

Among mechanical double-rod jacks, rack-and-pinion models, in which a folding pick-up is fixed to a tripod, deserve special attention. Compared to other mechanical jacks, rack and pinion jacks are available with lifting heights from 500 mm to 1 m.

The main advantages of mechanical devices include: compactness (they take up little space in the garage), ease of use, good stability, operational reliability and affordable price. As for the disadvantages, such jacks cannot be overloaded with unacceptable weight; they also have low efficiency.

Hydraulic

This type runs on hydraulic oil. Its operating principle is as follows: the drive pump creates oil pressure, which causes the plunger (piston) to move and starts the process of lifting the load to the desired height. After the working fluid enters the pump reservoir, the load begins to smoothly lower. A double-plunger jack has a lot of advantages, among which are high load capacity, smooth running, high efficiency and mobility of the structure.

In addition, hydraulic jacks are expensive.

In turn, hydraulic jacks are divided into bottle, rolling and special (hook, diamond-shaped).

Double-stock bottle models are considered the most popular and functional; they are characterized by a convenient design and long service life.

The rolling jack is widely used among car enthusiasts; it can be found in any garage. The design of the rolling device has the form of a trolley with a rigid frame that can withstand heavy loads. In addition, the design includes a protection valve; it is activated in case of overload and increases the safety of operation of the device.

The main advantages of rolling jacks include:

• complete autonomy;
• high efficiency;
• no need to expend effort and time;
• safe and convenient operation (can be used anywhere where a breakdown has occurred).

Such units have no disadvantages.