Processing various materials under strong physical pressure allows stamping, chopping, dressing and other operations. Similar works are organized in construction, manufacturing, transport and car services. Technical conditions for them are most often created by means of a hydraulic press, which is controlled directly by the operator without power auxiliary units.
Unit Overview
The pressing equipment has long been used by mankind as a simple and at the same time effective tool for exerting force on the workpiece. As the concept of piston mechanisms developed, more and more complex equipment variations appeared and today on the market you can find technological pneumohydraulic and electrohydraulic modifications. They work through an additional power plant and do not require direct human participation in this process. What are the advantages of vertical hydraulic presses working from physical force against this background? First of all, they have a lower cost and complete independence from third-party power supply and drive mechanisms. The unit is completely autonomous and requires only periodic maintenance with an oil change.
Press design
It must be emphasized right away that today various types of models are being produced, both structurally and functionally. For example, a desktop hydraulic press can be installed on a stationary workbench and perform small-scale editing of automotive parts. Classical vertical plants are used in production in line stamping of various products and blanks. That is, at least this equipment may have different sizes.
But, regardless of the form factor, any press of this type is based on a high-strength column bed with a reliable platform. On this base, functional units and auxiliary parts are fixed. A typical hydraulic press device provides for two cylinders with different diameters that communicate with each other. Their niches are filled with a special fluid that does not affect the metal of the structure, but at the same time performs the tasks of supporting pressure.
Operating principle
Units work according to the principles of hydrostatics. In particular, a law is in effect according to which the pressure exerted on a stationary gas or liquid will be uniformly transmitted in all directions associated with these media. This means that when pressure is applied to one of the aforementioned cylinders, the liquid in the second will raise the rod or piston. In this case, due to the difference between the volumes of the cylinders, you can get the additional force of the hydraulic press, which is involved in exerting pressure on the workpiece. That is, if earlier this mechanism was used as a means of lifting, then as the technology developed, the opposite effect, successfully used today in metal processing, was mastered. From workpieces deformation operations, engineers gradually switched to mechanical cutting, cutting, etc.
Specifications
So that the unit does not disappoint during operation with its parameters and capabilities, you should familiarize yourself in advance with what characteristics such equipment is evaluated in principle. It’s worth starting with maximum effort, which is expressed in tons. This is the magnitude of the load exerted by the piston on the workpiece. The average force of a hydraulic press is 20 tons, and the extreme values can be represented by a range from 5 to 50 tons.
In domestic conditions, for a garage or a small locksmith workshop, it is quite possible to limit the load to 10 tons. At large plants that work with solid-state materials, the required power potential can leave even more than 50 tons. By the way, heat-treated parts are served by machines, the force of which is 65 tons. In order not to make a mistake in choosing the load for a particular workpiece, you should refer to manometers - these are devices built into the design of presses that show the current working pressure.
A significant technical and operational parameter is the stroke. This characteristic of the hydraulic press determines the maximum dimensions of the parts available for processing and, on average, varies from 110 to 235 mm. From the point of view of the convenience of handling the workpieces, it will be useful to think through the design features in advance. For example, which unit is better suited - floor or table. And also to evaluate the height of the press, which also sometimes acts as a limiter for loading large-format billets.
Preparing the press for work
Before performing technical operations, you should familiarize yourself with the parameters of a particular unit in detail, which will minimize the risk of breakage. Next, the following components and parts are checked:
- Fixing connections. All nuts, brackets and screws are tightened. Particular attention is paid to the handle, which directly directs the force to the machine. It is important to consider that the operation of a hydraulic press is accompanied by high loads and vibrations. If a weak point is initially present in the structure, then it will become even more loose during operation, which can lead to breakage or injury.
- The free running of all movable parts of the unit is estimated. If necessary, replace the water or technical oil in the cylinders. For example, it is recommended to lubricate the press columns and plunger mechanisms with solid oil at each shift.
- Valve stems and plunger seals are inspected for physical defects. In order to promptly eliminate possible fluid leaks, these parts should be checked before and after operation.
Fluid Handling Tips
In the operation of updating water and oil in hydraulic equipment there is nothing complicated, however there are tricks that will help to save on this consumable. For example, the operational characteristics of the oil in the form of heat resistance, adhesion and viscosity will remain longer if the liquid is protected from fine dust, litter and dirt during the entire period of storage and direct use. It is also recommended to protect the composition from direct sunlight and air.
The loss of working properties will be indicated by the darkening of the liquid, the formation of slags and organic acids in the composition. Again, maintaining performance is important primarily for the hydraulic press itself, the surfaces of its structure, which have direct contact with technical oil and water filler.
If the oil is clogged, then do not rush to a complete replacement. You can clean it using special filters. In locksmith workshops and factories, perforated sheet metal membranes are used for these purposes. Wire and cloth layers of the filter will also allow you to get rid of small impurities.
Trouble-shooting
The presence of breakdowns will be indicated by uncharacteristic knocks, excessive vibrations or insufficiently powerful force when lowering the valve. Among the causes of incorrect operation of the unit may be air in the cylinders, incorrect adjustment of the design, errors when replacing valves and rods, as well as jamming of individual functional parts. In each case, there will be its own sequence of actions aimed at restoring the equipment to working capacity, and at home, you can perform the following repair operations:
- Full adjustment of the valve stroke of the hydraulic press, as well as elimination of gaps and excess air.
- If there are inconsistencies in the connection of the pipes for draining the liquid or other communications to the cylinder system, then it will be possible to compensate for the violations with throttle washers by choosing the right diameter.
- Jams and wedges are eliminated only during the disassembly of the problematic mechanism. Prevention of such situations is expressed in timely and sufficient lubrication of the working surfaces.
Proper machine care
In order not only to eliminate the risk of the above-mentioned malfunctions, but also to extend the basic operational life of the unit and its parts, its condition should be maintained in proper form. The key to good work and durability is clean external and especially internal surfaces. Dirt, dust, foreign objects and other garbage - all this must be eliminated in time. For the routine cleaning of surfaces, a cotton cloth is used that effectively collects not only dirt, but also moisture.
Since the manual hydraulic press has a lot of inaccessible grooves and holes in the design, comprehensive care cannot be avoided without a compressor with a cleaning gun. A supply of compressed air will clean these areas, eliminating clogged impurities. Another way to deal with dirt in hard-to-reach places is to use a thin stick with a wound cleaning cloth or a piece of cloth. The fabric can initially be moistened with a detergent for metal surfaces.
Hydraulic Press Manufacturers
High-power units with high-quality assembly and element base are manufactured by TORIN, Ombra and Sivik. In particular, the TY50001 50 tonne unit from TORIN receives good reviews. The manufacturer AE&T, on the contrary, is famous for its well-assembled machines of low productivity - for example, you can highlight the T61204 modification of 4 tons, designed to work with hard landing parts. In the domestic segment, the companies SOROKIN and STOK stand out, also for the most part offering entry-level equipment. As a universal hydraulic press for 20 tons, you can buy a decent model SD0805C with a foot drive from the company "Stankoimport".
Equipment application
Despite the morally obsolete principle of operation, or rather, the approach to its application, hand-operated hydraulic systems are still used in various fields of production, construction and household facilities. With the help of such units, lumber is made, plastics are squeezed into molds, metal blanks are cut and flanging is performed. In ordinary garages, you can find a desktop hydraulic press that allows you to bend individual parts of the body, parts of the chassis, etc. without the help of specialists. In professional auto repair shops on powerful machines, you perform shaft dressing, press in bearings and bushings, and also fix large-format elements with large section.
Conclusion
When choosing suitable equipment for exerting force pressure, several points should be taken into account. Firstly, the basic technical and operational characteristics. Secondly, the very scheme of work, due to the structural and functional capabilities of a particular machine. And also do not forget that a manual hydraulic press is part of a wide group of equipment operating under high pressure due to liquid. It would be useful in principle to assess the feasibility of acquiring just this type of pressing equipment. Still, in terms of convenience and load, it is inferior to pneumatic and electrical analogues. But, on the other hand, manual hydraulic systems cost less and are not dependent on other energy sources.