What is a four column hydraulic press?
The Four Column Hydraulic Press is a type of mechanical equipment used to process various materials such as metal, plastic, rubber, wood, gunpowder, among others, using the static pressure of hydraulic oil generated by an oil pump.
See too:
- Hydraulic Press 101: Everything You Need to Know
What is the working principle of four column hydraulic press?
The hydraulic transmission system of a Four Column Hydraulic Press is composed of five components: power mechanism, control mechanism, executive mechanism, auxiliary mechanism and working medium.
The power mechanism typically uses an oil pump as a power source, which is generally a product oil pump. To satisfy the actuator movement speed requirements, one or more oil pumps are selected. This may include a gear pump for low pressure (oil pressure below 2.5 MP), a vane pump for medium pressure (oil pressure below 6.3 MP), or a plunger pump for high pressure (pressure of oil below 32.0 MP).
This hydraulic press is used for pressure processing and forming of various plastic materials, such as extrusion, bending and stretching of stainless steel plates, as well as cold pressing of metal parts. In addition, it can be used to press powder products, grinding wheels, Bakelite and thermosetting resin products.
Four Column Hydraulic Press Working Medium
Process of evolution of the working environment
Initially, the hydraulic press used water as a working medium. However, to improve lubrication and reduce corrosion, a small amount of emulsified oil was added to form an emulsion as the working medium.
Later, at the end of the 19th century, mills using mineral oil as a working medium appeared. This type of oil has excellent lubricating properties, corrosion resistance and moderate viscosity, which improves the performance of the hydraulic press.
During the second half of the 20th century, a new type of water-based emulsion was developed. Unlike the original “oil in water” emulsion, this new form was an “oil in water” emulsion.
The external phase of the “oil in water” emulsion is oil, which offers lubricating and corrosion resistance properties similar to those of oil. However, its oil content is low, making it less prone to combustion.
Despite its benefits, the cost of water-based emulsion is relatively high, which has limited its widespread use.
Function of the working environment
The working medium used in the hydraulic press has a dual purpose: it not only transmits pressure, but also ensures that the machine's working parts are sensitive, reliable, long-lasting and have minimal leakage.
Basic requirements for work environment
The basic requirements for the working medium of the hydraulic press are as follows:
- Appropriate fluidity and low compressibility to increase transmission efficiency.
- Ability to prevent rust and corrosion.
- Good lubrication performance.
- Easy to seal.
- Oxidation resistance, performance stability and ability to maintain optimal performance over a long period of time without degradation.
What are the types of four column hydraulic presses?
The Four Column Hydraulic Press, also known simply as the Hydraulic Press, is a machine powered by liquid pressure, which is based on Pascal's law. There are many different types of hydraulic presses available.
Applications of hydraulic presses vary depending on specific requirements. There are two main types of hydraulic presses based on the type of liquid used to transmit pressure.
The hydraulic press generates substantial total pressure, making it a common choice for forging and stamping operations.
Hydraulic forging press can be divided into two types: hydraulic forging press and hydraulic free forging press. Hydraulic forging press requires a mold, while hydraulic free forging press does not.
Four Column Hydraulic Press Components
The Four Column Hydraulic Press consists of two main components: the main machine and the control mechanism.
The main machine includes hydraulic cylinder, beam, column and liquid filling device. The power mechanism is composed of oil tank, high pressure pump, control system, motor, pressure valve, directional valve and other components.
The hydraulic press is ideal for the pressing process of plastic materials, including powder product molding, plastic product molding, cold (hot) extrusion metal molding, sheet stretching and cross pressing, bending, turning, correction and other processes.
The four-column hydraulic press has an independent feeding mechanism and electrical system. It is centrally controlled using buttons and offers three operating modes: adjustment, manual and semi-automatic.
Structural form of four column hydraulic press
Hydraulic presses are classified into two types based on the direction of applied force: vertical and horizontal.
Most hydraulic presses are vertical and used for extrusion purposes, while structural presses are typically horizontal.
In terms of structural design, hydraulic presses come in several varieties, including double column, four column, eight column, welded structure and multi-layer steel strip winding structure. Medium and small vertical hydraulic presses also come in C-shape.
The C-frame hydraulic press is open on three sides, making it easy to operate, but it lacks rigidity. On the other hand, the hydraulic press with welded structure for stamping has a good level of rigidity and is open at the front and back, but closed at the left and right.
In a four-column vertical free forging hydraulic press, the oil cylinder is fixed on the upper beam and the plunger is rigidly connected to the movable beam which is guided by the column and moves up and down due to the pressure of the working fluid . The beam has working tables that can move back and forth, and the upper anvil and lower anvil are installed under the moving beam and the working table respectively. The workforce is transported by the gantry composed of upper and lower beams and pillars.
For larger and medium free forging hydraulic presses driven by a pump accumulator, three working cylinders are typically used to obtain three-stage working power. The working cylinder is also equipped with a balance cylinder and a return cylinder that apply upward force.
Equipment Features of Four Column Hydraulic Press
The machine is equipped with an independent power mechanism and electrical system, and can be centrally controlled using buttons to obtain three working modes: adjustment, manual and semi-automatic. The working pressure and pressing speed, as well as the stroke and range of no-load rapid descent and deceleration, can be adjusted to meet the requirements of the pressing process. The ejection process can also be completed.
There are three process modes available: ejection process and stretching process, each with two process actions: constant pressure and constant stroke. The constant pressure forming process includes ejection delay and automatic return after pressing.
The machine has an independent power organization and electrical system and can be centrally controlled through adjustment buttons and semi-automatic operations. The mobile work platform is driven by a frequency conversion controller, and its electrical equipment is a world-leading PLC programmable controller. YH25-315D “T” type mobile action platform has been improved in design and production, which improves the automation level of the hydraulic press series, increases production power and reduces operator labor intensity.
The hydraulic press uses liquid as the energy transfer medium and has an advanced slave and master cylinder hydraulic circuit, resulting in low oil temperature. The idle travel speed is greater than 10 mm/s, the working speed is less than 20 mm/s, and the equipment operates silently with noise levels less than 75 db when the sliding speed goes up and down.
The machine adopts a four-column and three-plate structure and has a vertical moving plate precision controlled by four precision guide sleeves. The parallel accuracy between any point on the lower working face and the upper working face is less than 0.08 mm.
What are the product advantages of four column hydraulic press?
There are several types of hydraulic presses available on the market, each designed to be suitable for processing different parts and materials.
Many large-scale material processing and metal material production facilities now commonly use the four-column hydraulic press because it is economical and easy to use.
So what are the advantages of Four Column Hydraulic Press?
1. Precision forming, small tolerance and high precision
The pressure generated by the Four Column Hydraulic Press is stable, which reduces die wear and leads to more accurate product formation under numerical control. The forgings produced are of high quality, with minimal burrs and small tolerances, resulting in high precision.
This hydraulic press allows for less cutting processing and eliminates the need for additional turning, milling and planing processes. For example, the tooth shape of cylindrical gears and bevel gears can be directly formed and produced.
2. The human-machine interface is interactive
The hydraulic press motor is digitally controlled, and the user can input simple displacement and speed parameters to achieve intelligent and flexible numerical control of the process curve. This eliminates the need for the user to compile the process curve, making it extremely convenient to use.
3. High service life
Numerical pressure control ensures that the mold does not become overloaded, worn or damaged.
4. High efficiency and energy saving
The four-column hydraulic press has multiple energy-saving features, including no clutch friction power consumption, no flywheel idling power consumption, and high engine efficiency. These features make the servo press efficient and economical.
5. High equipment reliability
The Four Column Hydraulic Press equipment has no wearing parts, which makes it more durable. The motor's rotor has no windings, conductors, or permanent magnets, making it stronger than a permanent magnet servo motor. It is solid and reliable, as well as impact resistant. Maintenance-free equipment saves maintenance personnel and reduces the time required for maintenance.
6. Adjust intelligently
The body of the Four Column Hydraulic Press is equipped with a tonnage gauge that allows mold adjustment and testing under pressure control. The mold can be adjusted slowly and without stopping the machine, eliminating the need for special mold adjustment and testing equipment and personnel. This saves mold adjustment work and reduces the time required for the task.
7. Intelligent automatic numerical control
The operation of the Four Column Hydraulic Press is controlled by high-speed computational intelligence, allowing full automation without the need for manual operation.
What are the benefits of using a four-column hydraulic press?
Reduce quality and save materials
For typical parts such as automobile engine mounts and radiator supports, hydroformed parts are 20% to 40% lighter compared to stamped parts. For hollow parts with a stepped shaft, the weight reduction can reach 40% to 50%.
Reduce the number of parts and molds and reduce mold cost
Hydroforming parts typically require only one set of dies, while stamping parts typically require multiple sets of dies. For example, the number of parts of the hydroformed engine mount can be reduced from 6 to 1, and the number of parts of the radiator support can be reduced from 17 to 10.
Can reduce the amount of subsequent machining and assembly welding
For example, with the radiator support, the heat dissipation area increased by 43%, the number of solder joints was reduced from 174 to 20, the number of processes was reduced from 13 to 6, leading to an increase in productivity by 66%.
Improve strength and stiffness, especially fatigue resistance
For example, the stiffness of the radiator support formed through hydroforming can be increased by 39% in the vertical direction and 50% in the horizontal direction.
Lower production cost
According to statistical analysis of hydroformed parts in use, the production cost of hydroformed parts is 15% to 20% lower compared with stamped parts, and the cost of dies is 20% to 30% lower.
Safe operation of four-column hydraulic press
- Before operating the hydraulic press, the operator must undergo training and master the equipment's performance and operating techniques.
- Clean all mold debris and any dirt on the hydraulic press rod before starting operation.
- The hydraulic press must be installed with the power turned off and it is prohibited to activate it by pressing the start button, handle or pedal.
- Correctly install and align the upper and lower molds and adjust the mold gap, ensuring they are centered. Confirm that the molds are correctly placed before starting the press.
- Before using the hydraulic press, let the equipment idle for 5 minutes to check the oil level in the tank, the sound of the oil pump and whether there are leaks in the hydraulic unit, pipes, gaskets and pistons.
- Perform a pressure test by turning on the equipment and checking that the pressure reaches the working pressure and that the equipment operates normally and reliably without leaks.
- Adjust the working pressure, but it must not exceed 90% of the equipment's nominal pressure. Test a sample part and begin production after passing inspection.
- For different configurations of hydraulic presses and workpieces, adjust the working pressure, number of presses, and pressure retention time during the pressure adjustment and calibration process to avoid damage to the molds and workpieces.
- Do not extend your hands or heads on the workpieces of the pressing plate and mold when the pressing plate of the machine body moves up and down.
- It is strictly prohibited to manipulate the part in any way (hitting, stretching, welding, cutting, bending or twisting) while applying pressure.
- Smoking, welding, cutting and hot work are not permitted near the hydraulic press, and flammable and explosive materials must not be stored on site. Appropriate fire prevention measures must be taken.
- After using the hydraulic press, turn off the power supply, clean the hydraulic rod, add lubricating oil, and carefully clean and store the molds and workpieces.
Four-column hydraulic press maintenance
Common faults and maintenance techniques for four-column hydraulic presses: Precision parts often appear in the hydraulic transmission system.
Although hydraulic transmission in machines is known for its convenience and labor-saving benefits, it is also prone to damage.
The main cause of this is a lack of understanding of its operating principle and structural characteristics, resulting in an inadequate understanding of preventive maintenance techniques.
There are three main factors that contribute to hydraulic system problems: contamination, overheating and air ingress.
These three factors are closely related and can lead to additional problems if any of them occur.
Practice has shown that 75% of problems in the four-column hydraulic press system can be attributed to these three factors.
- Deterioration of working oil due to contamination:
- Overheating:
- Air Ingress Solution: Clean and assemble key system precision parts in a clean room to minimize contamination.
The clean room must have a clean floor, closed doors and windows and maintain a temperature of approximately 20°C.
Other common maintenance:
- For hydraulic oil, L-HL32/GB1118-89 or N32/GB3141 can be used when the temperature is below 20°C, and N46/GB3141 can be used when the temperature is above 30°C. It is recommended to use 32# and 46# anti-wear hydraulic oil for working oil, with an oil temperature range of 15-60°C.
- Oil should only be added to the tank after undergoing rigorous filtration by the oil industry.
- The working oil must be replaced once a year, and the first replacement must not exceed three months.
- Regularly lubricate the slide block with oil and keep the outside of the column clean. Spray oil before each operation.
- With a nominal pressure of 500t, the maximum allowable eccentricity of the concentrated load is 40mm. Excessive eccentricity can cause spinal strain or other undesirable results.
- Calibrate and inspect the pressure gauge every six months.
- If the machine is not used for a long time, clean the surface of each component and coat with anti-rust oil to prevent corrosion.
1. How to select hydraulic oil for four column hydraulic press?
After identifying the characteristics of the oil used, such as viscosity, density, vapor pressure, air solubility, volume modulus, anti-combustibility, temperature range, pressure range, lubricity and compatibility, and selecting or equipping hydraulic oil based on specific requirements, the issue of working medium in the hydraulic system can be resolved.
However, inappropriate use can still alter the properties of the oil. For example, it is commonly believed that the viscosity of oil at a given temperature and pressure is constant, regardless of activity. In reality, oil viscosity will decrease significantly after excessive shear.
2. To ensure the stability of the four-column hydraulic press under the condition of using hydraulic oil
For hydraulic oil that has been used for a long time, the temperature range is determined by its oxidation and thermal stability.
Therefore, hydraulic oil must be stored, transferred and filled at a temperature below its initial oxidation temperature for a long period, avoiding contamination during storage, transfer and filling.
Regular oil samples and inspections should be performed and a regular oil change schedule should be established.
Ensure adequate oil storage in the tank to facilitate heat dissipation in the hydraulic system and maintain system sealing.
Immediately clean up any spills that occur.
Four Column Hydraulic Press Troubleshooting
Common faults and protection techniques for four-column hydraulic presses: Precision parts often appear in the hydraulic transmission system.
Although hydraulic transmission in machines is known for its convenience and labor-saving benefits, it is also prone to damage.
This is due to a lack of understanding of its operating principle and structural characteristics, resulting in an inadequate understanding of how to prevent and protect it.
The hydraulic system has three main factors that contribute to problems: contamination, overheating and air intake.
These three factors are closely related and can lead to additional problems if any of them occur.
Practice has shown that 75% of problems in the hydraulic system can be attributed to these three factors.
Action failure
- Electrical Wiring Problems: If the electrical wiring is not secure or connected incorrectly, compare the circuit to the electrical diagram to resolve the problem.
- Insufficient oil in oil tank: To troubleshoot insufficient oil filling, add oil to the appropriate level.
Sliding Block Tracking
- Air buildup in the system or pump oil inlet: To resolve this problem, check the oil suction tube and operate the system up and down several times while pressurizing.
- Incorrect precision adjustment or lack of oil in the column: To resolve this problem, readjust the precision and add oil to the column surface.
Down with pressure
- Excessive support pressure
Troubleshooting: Adjust the pilot valve and use pressure no more than 1MPa.
- Sliding block seriously slides after stopping
Cylinder port (or piston) seal ring leaks oil
Troubleshooting: Check the sealing ring and replace it if it is damaged.
- Pilot valve preset pressure is too small
Troubleshooting: Adjust the pressure value
- Poor cartridge valve port seal
Troubleshooting: Check valve port and replace
- The pressure gauge needle fluctuates a lot
There is air in the pressure gauge oil passage.
Troubleshooting: Loosen the connector to bleed when pressing it.
- Gas pipeline mechanical vibration
Troubleshooting: Check the tubing for looseness, and if it is loose, secure it securely.
- Damaged pressure gauge
Troubleshooting: Replace the pressure gauge.
- At high speed, the traveling speed is not sufficient and the upward pressure is slow.
The variable flow of the pressure compensation pump is too small.
Troubleshooting: Adjust according to the requirements of the oil pump.
- Worn or burned pump
Troubleshooting: If the oil output from the oil pump oil drain is more than 4L/min, it must be removed for maintenance.
- Oil leak in the system
Troubleshooting: Check the corresponding links of each part.
Pressure fall
- The valve ports involved in the seal are not hermetically closed or the piping leaks oil.
Troubleshooting: Check whether the corresponding valve seal fastener is damaged and replace it if it is damaged.
Repair and weld the leaking pipeline and check whether the pressure commissioning is normal.
- The master cylinder sealing ring is damaged.
Troubleshooting: Replace the sealing ring.
The information above provides an overview of the situation. When a fault is identified during actual use, it is important to first analyze the cause before taking any troubleshooting steps.
How to buy four column hydraulic press?
In China, the selection of a hydraulic press should be based on the nature of the production process, batch size, mold conditions, accuracy requirements and other factors due to the variety of hydraulic press models and their different levels of rigidity, precision and methods of use.
The four-column hydraulic press is a piece of equipment widely used in industrial production, but it can be difficult to find a cost-effective option.
For those who frequently use and operate a four-column hydraulic press, finding suitable equipment can be a challenge.
It is recommended that purchasing partners determine their specifications based on their actual needs and follow the following principles:
1. You need to select the appropriate model and equipment according to your own needs .
① Before purchasing, it is important to determine the shape and raw material to be pressed, the desired yield, and any special requirements for the four-column hydraulic press. The manufacturer should then be consulted to provide the appropriate model.
② When choosing a four-column hydraulic press, it is important to ensure that the pressure is suitable to improve the service life of the equipment and support future development. The nominal pressure must be higher than the actual working pressure.
③ The production of four-column hydraulic press not only depends on the model, but also on the hydraulic system of the equipment. A fast system is important.
④ The stroke of the four-column hydraulic press must be sufficient to accommodate the size of the molded product and allow easy removal from the mold.
2. Select the appropriate manufacturer
The quality of a four-column hydraulic press not only affects its service life, but also affects production efficiency.
After determining the desired equipment model, it is advisable to contact several companies to collect information about hydraulic press prices, parameters, delivery methods and other relevant details.
It is also recommended to visit the processing plant for an on-site investigation to assess the scale of production, actual processing capacity and technical capabilities of the company in order to determine the quality of the equipment being produced.
(1) The appearance design of the four-column hydraulic press should be reasonable, with uniform and smooth painting and a smooth surface without corrosion.
(2) When testing the equipment, check whether there are any abnormal noises or mechanical vibrations.
Test the pressure effect of the four-column hydraulic press and make sure it runs smoothly during the test.
See too:
- How to choose the right hydraulic press?
- Top 15 Hydraulic Press Manufacturers (Oil)
3. Understand the manufacturer's after-sales service
Many people do not have a clear understanding of the four-column hydraulic press. Installation and commissioning are crucial to equipment performance and efficiency.
It is important not to sacrifice after-sales service in pursuit of a low price or to assume that it is included with expensive equipment. It must be specified in the contract as a separate clause.
When considering purchasing a hydraulic press, in addition to evaluating the factors mentioned above, it is important to provide the press supplier with detailed performance requirements, including safety, ease of maintenance, installation cycle and cost.
For the manufacturer, key considerations include: production cycle, budget, mold design, part structure, number of mold changes, external dimensions of the press, and the purpose of the design.
Advancement in science and technology highlights the importance of maintaining close contact and communication with various hydraulic machine manufacturers to make an informed and sensible decision. This is the best way to ensure you select a high-quality hydraulic press.
