According to different structures, hydraulic presses can be divided into a two-post hydraulic press, C-frame hydraulic press, four-post hydraulic press, etc. Now we’ll talk about the four-post hydraulic press, which is commonly used by manufacturers nowadays.
If you want to update your two-post or C-frame hydraulic press, then you can never miss the four-post hydraulic press. Due to its four-column structure, it has higher rigidity and larger access to the working area than two-post and C-frame hydraulic presses.
Four-column hydraulic presses are usually guided by quality graphite-impregnated self-lubricated bronze bushings, as a result of which, they generally do not need external lubrication and have a longer service life.
Four-post hydraulic presses are often compared with gib-guided presses which have even higher precision but are more expensive. Four-post hydraulic presses, which are supported by four chrome-plated columns, can never fail to achieve ideal rigidity and precision level; their prices are also cheaper than gib-guided presses. Therefore, it is considered to be more cost-effective than gib-guided presses.
When compared with a two-post hydraulic press and C-frame hydraulic press, a four-post hydraulic press is open from side to side and front to back, so it has wider access to the working area and it’s more convenient for operators to perform routine operations. Besides, because it has four columns to connect and support the top and bottom platens, it also has a higher level of stability and rigidity than two-post and C-frame types.
In view of the above, four-post hydraulic presses have been one of the forming machines that are mostly sought by manufacturers.
The four-column hydraulic press is mainly composed of three parts: the main engine, the hydraulic control system, and the electrical control system. The main engine includes a workbench, guide column, sliding block, upper cylinder, ejection cylinder, and others; the hydraulic system of the four-column hydraulic machine is composed of control components, execution components, auxiliary components, power devices, and working media; the electrical control system of the four-column hydraulic machine is mainly composed of relays, contactors, buttons, travel switches, electrical control cabinets, etc.
The working principle of the four-column hydraulic press is as follows: the electric control system controls the hydraulic system, and then the hydraulic system controls the main engine to work. The main engine touches the travel switch and the signal is fed back to the electric control system to realize cyclical control.
1. There are two speeds available: fast no-load speed, and slow working advancement speed towards the die.
2, Upper and lower limits are devised to protect the main cylinder and press cylinder. And it is also convenient to set the upper and lower limit position.
3. The hydraulic system uses a cartridge valve that has a large flow, high speed, low noise, and low heat.
4. Since there is four-sided wide access to a four-post hydraulic press, grating safety protection devices are often added for the sake of safety.
5. Four-post hydraulic press has evolved to achieve lower energy consumption while still having high efficiency.