Nowadays, the types of hydraulic presses sold on the market are diverse, and their functions are also different.
In addition, the quotations of different hydraulic press manufacturers are also very different, so we will feel confused when choosing a hydraulic press and don’t know which kind of hydraulic press to choose.
Now I’ll teach you how to choose the right hydraulic press.
Method to choose the right hydraulic press
In the past, people’s understanding of “stamping” was different, and some people equated stamping with blanking.
A few years ago, mechanical press and screw press were mainly used for stamping. Now this situation has changed and hydraulic press has been used.
Hydraulic press appeared in the late 1930s. Many hydraulic presses are used to assist forming processing, such as punching, piling, rivets, embossing, shearing, crimping, etc. some have been used for blanking and stamping.
Only when we really understand the definitions of stamping, blanking and deep drawing can we decide whether to use hydraulic press.
Blanking is to cut, shear and punch the plate to make it into the shape we need. The material can be a single sheet of thin plate or a continuous step long plate.
Stamping can be understood as blanking, but it also includes forming, bending, flanging, punching processes. On the basis of blanking and the above processing types, the press can be called forming press.
Deep drawing refers to the process of positioning the blanking part in the die. When the press is stamping, the blank holder controls the metal flow to form a cavity workpiece.
Generally speaking, deep drawing refers to the workpiece whose depth of the drawn part or concave part exceeds 1 / 2 of its diameter.
Generally speaking, the mechanical press has the advantages of simple structure, fast production beat and high efficiency. It is suitable for mass and simple blanking and forming processing.
The hydraulic press is suitable for small and medium-sized batch production. It has JIT requirements, changeable shape, more accurate requirements for the speed, pressure and position of the slider, and is processed according to the order.
BlankingNow, hydraulic press is generally used for blanking of small and medium-sized parts with low productivity requirements, and its production beat generally will not exceed 20-40 pieces per minute.
According to the size of the workpiece, pressure load (centering or eccentricity) and forming mode, the structure of the press is C-shaped frame, double column or four column press, and its body structure must be able to withstand the impact and vibration caused by blanking.
C-shaped single column press will deflect the angular wave die during stamping;
The trajectory of the action point of the force of the four column press deviates from its geometric center, while the two column press has stable structure, accurate action and little deflection, which is suitable for eccentric load processing.
Designers often design the weight of the blanking press to be twice as heavy as the standard configuration, so as to improve its firmness and reduce the impact of blanking.
For the blanking process meeting the following requirements, it is ideal to use hydraulic press.
1. Slow production pace
60spm when processing small parts (1-2 inches); When processing large parts (3-15 inches), the speed is 30-40 SPM.
2. Complex program settings
For diversified product types, complex program setting is often required, which is easy to set with hydraulic press.
3. JIT parts are replaced frequently
When this is required, the setting can be changed quickly using a hydraulic press.
4. Setting difficult
Only by knowing whether the stroke range of the slider and the adjustment of the pressure control meet the processing requirements can we find the benefits of using the hydraulic press.
When designing the press, if the stroke range is set, the hydraulic press should be selected.
Similarly, it is easy to set the preload of the hydraulic press.
Preloading is used to counteract the impact of workpiece weight or emergency stop.
5. Buffer function (press may be damaged when pressing two pieces)
When two pieces of material are fed to the die during feeding, or when parts are discharged from the die, the device fails to eject the machined parts.
It is possible to press two pieces at this time. In this case, the mechanical press may be damaged, and the hydraulic press will not be damaged because it has overload protection function and limits the maximum pressure.
Hydraulic presses with various configurations are widely used in stamping processing, and the most commonly used are:
- 20-250TCsingle column press (processing small parts);
- 50-1000Tfour column press (processing large and medium-sized parts);
- Double column press (for processing large workpieces with conveyor or eccentric pressure);
- There are few double column presses with working pressure above 5000t.
Hydraulic press shall be selected for stamping with the following requirements:
1. Mixed processing of large and small parts
2. Die replacement frequency is high and JIT requirements are met
Because the hydraulic press is easy to set up, it can be completed in a few seconds.
3. Feeding method
The feeding method is manual feeding rather than automatic feeding, which depends on the processing batch. For small batch production (less than 100000 pieces per year), manual feeding is used; In mass production, some or all of them use automatic feeding mechanism.
4. With eccentric load
If eccentric pressure is required, double column press shall be selected.
5. Jacking mechanism
Hydraulic press shall be selected if hydraulic pad is to be used during material support or automatic discharge
6. When the requirements for slider and pressure control are high
When different processing speeds or position control of the slider are required, the position accuracy is required to be high and the pressure is required to be maintained for a long time, the hydraulic press shall be selected.
7. Flexibility of installation
When another project needs to use this hydraulic press, it needs to be reinstalled.
For example, when the production line changes, because the maximum pressure can be used at any stage of the stroke, the press can be easily reset.
Because the hydraulic press can accurately control the slider speed, the metal material is allowed to flow without tearing during drawing, so the hydraulic press is used for deep drawing.
The hydraulic press is suitable for the following drawing processes: deep drawing with low output, frequent die replacement, requiring a variety of drawing speeds, large pressure change of hydraulic pad and high pressure regulation requirements.
Hydraulic press is recommended for deep drawing in the following cases.
1. The workpiece is complex and the setting is required to be simplified
Because the workpiece design is complex, the required processing procedures are also complex, and the adjustment of the hydraulic press is simple, which is suitable for this situation.
2. Press structure
When a single press is required to complete processing or there are multi-step drawing and shaping processes, a hydraulic press can be used.
The hydraulic press is also suitable for single line production of deep drawing and / or reverse drawing. Due to the pressure stroke limit, it is suitable for finishing processing.
3. Full pressure requirements
The hydraulic press can keep the maximum pressure unchanged in the drawing process, which can reduce the tonnage requirements of the press.
When you decide to purchase hydraulic press, in addition to evaluating several factors involved in this post, there are safety, easy maintenance, installation cycle, cost, etc.
You should also provide the press supplier with your requirements for the performance of the press as detailed as possible.
The key to the manufacturer are: production beat, budget, mold design, workpiece structure, number of mold changes, overall dimensions of the press, and the purpose of the project.
The development of science and technology shows that in order to make a correct and wise choice, you must keep close contact and communicate with different press manufacturers.
Only in this way can we correctly select and make full use of a press.
What key factors should be paid attention to when purchasing hydraulic press equipment
Hydraulic press equipment is widely used in various industries.
The equipment has a high degree of automation and high precision.
The hydraulic system is an important part of equipment operation. Its performance determines the overall quality of the hydraulic press.
Therefore, when purchasing a hydraulic press, we should focus on all parts of the hydraulic system.
The quality of these components such as hydraulic pump, hydraulic valve and oil cylinder is directly related to the stability of the performance of the hydraulic press.
Hydraulic pump, hydraulic valve, oil circuit block, motor and oil pipe are the main components of hydraulic pump station.
No matter which part will seriously affect the use function of hydraulic press, we should pay special attention to the selection of these equipment, and we should not make serious mistakes due to carelessness.
The hydraulic pump is a stable power source.
The displacement of the pump shall be moderate and not too large. If the displacement is too large, it will lead to the hydraulic oil that meets the requirements of equipment operation entering the oil return pipe through the overflow valve.
At this time, the overflow will produce pressure loss under the specified pressure, resulting in the increase of system temperature, which will directly affect the working performance of the equipment.
Therefore, it is suggested that we reasonably select the hydraulic pump to avoid the pressure loss of the system.
At the same time, the quality of oil cylinders and molds is also very important.
Only good quality can be used for a longer time.
If the quality is not good, there will be more times of replacement, which will naturally cost more.
Therefore, we remind users to make more investigation and purchase reasonably.
There are many manufacturers of hydraulic press, and there are not a few who make up for the number.
Don’t trust any manufacturer because of low price.
Therefore, when purchasing hydraulic press, big proponents should pay special attention to quality, regardless of price.
In order to protect your own interests, please choose carefully.
It is suggested that the purchasing partners of hydraulic press should determine the purchasing specifications according to the actual needs at home, and generally follow the following principles:
1. Users need to know what the workpiece processed by their own hydraulic press is and whether there are special requirements for the hydraulic press.
At the same time, if the scale and form are expanded, consider whether there is some room for demand.
2. Understand the hydraulic press process.
For example, the rated pressure of the equipment must be greater than the rated pressure of the stamping process, but for the long stroke process, it must meet not only the process force, but also the working load curve.
In terms of stroke number, the hydraulic press shall meet the requirements of productivity.
3. The slider stroke of hydraulic press shall meet the requirements of workpiece height.
After stamping, it can be taken out of the die smoothly. For stretched parts, the stroke shall be more than twice the height of the parts.
The dimensions of sliding block and die handle hole shall meet the requirements for correct installation of die.
For the crank press, the closing height of the die should be between the large height of the die and the small height of the die.
Generally, the size of the workbench shall be greater than 50-70mm (one side) of the mold base under the mold for installation, and the hole diameter of the base plate shall be greater than the protruding size.
For the workpiece or waste, the size of the missing die handle shall be consistent with the size of the die handle hole.
How to correctly select hydraulic press manufacturers
Hydraulic press, as a widely used equipment in modern industry, quality, brand and price are the first consideration of many enterprises and institutions in the process of selecting hydraulic press.
As we all know, the brand effect has a great impact on the price. There is likely to be a big gap in the price of the same equipment with different trademarks.
Therefore, more and more small and medium-sized enterprises will give priority to the hydraulic press with high cost performance, but they often ignore the details of purchasing the hydraulic press. Here are a few points for your reference.
Hydraulic press is an equipment composed of many accessories. At the same time, I believe that few hydraulic press manufacturers produce the whole hydraulic press by themselves.
In other words, many parts need to be transferred or purchased. The key parts are produced by themselves and then assembled into a complete machine for sale.
I believe many people who have used hydraulic presses should know that the most common problem of hydraulic presses is oil leakage, which is inconvenient to repair.
They can either break them up and check them a little, which takes a long time, and the probability of repair is ridiculously low.
Or you can only do some simple processing and continue to use it.
Is the technology of the hydraulic press manufacturer not in place, so the hydraulic press leaks oil?
Or is it because the quality of parts is unreliable, wear and oil leakage?
Of course, because of the latter.
Therefore, the quality of accessories directly affects the quality of hydraulic press.
If you want to improve the quality of accessories, you can only choose the brand. The high brand price leads to the high price of hydraulic press, which is an unalterable equation.
Therefore, it is easy to judge whether the price is unreasonable according to the accessories when selecting the hydraulic press.
You can put aside your worries about whether there will be quality problems after purchasing it, which will affect your work.
The configuration is different from that of accessories. The configuration of hydraulic press can also be divided into high, medium and low configurations according to the requirements of different products and enterprises and institutions.
The same equipment, ordinary electric certainly can not compare with fully automatic, the efficiency is different, and the operation is complicated and simple.
Therefore, when selecting the hydraulic press, we must be clear about the equipment scheme and configuration given by the supplier.
Configuration that directly affects the price of hydraulic press:
- Maximum opening height
- Number of cylinders
- Other parameters
Here, by the way, common quotations of hydraulic press.
When quoting, many manufacturers often quote low prices in order to attract customers. In the process of negotiation, they increase the price a little bit.
As we all know, there will be a gap between equipment tax and non tax;
There will be a gap between manual and PLC control;
There is another gap between include mold and no mold;
As for the freight, some customers will ask the manufacturer to pay on their behalf, which will be calculated separately.
Therefore, when choosing a hydraulic press, you should understand the price given by the supplier, what it contains and what it does not contain.
Then compare it with several other companies to find the most cost-effective manufacturer.
Instead of direct inquiry, regardless of configuration, and then comparison, it will often spend more wronged money, and the final selected one is not the best.
Tips for choosing the right hydraulic press manufacturer
- Analysis from qualification
Obtain business license, tax registration certificate, organization code, production license and quality certificate, and analyze whether the enterprise’s production life, registered capital and quality supervision system are perfect;
- Review the production strength of the enterprise
Let the enterprise take photos of the strength of processing equipment, production site, finished products and semi-finished products under production;
- Ask for the sales performance of the manufacturer
See if there is a sales contract for at least five years and whether there has been a large hydraulic press, hydraulic press and press provided with military enterprises and state-owned listed enterprises.
Generally, the above performance can show that the production capacity and quality of the enterprise are good.
Generally speaking, large enterprises are very cautious in choosing large hydraulic presses;
- Talk from a technical level
Analyze the technical quality of the business personnel of the equipment manufacturer. The business personnel of powerful production enterprises are often trained, and large enterprises have high requirements for business personnel. They will not be allowed to engage in business and economic work without considerable diploma and strength;
- Do not blindly pursue low prices
There must be a problem with low-cost equipment. Ask about the market price of the first-line state-owned enterprises.
Generally, 80% of the equipment price of state-owned enterprises is selected. This product is generally the best cost-effective;
- Analyze the feeling of conversation
Powerful manufacturers and business personnel are very impressive. For example, there are little concessions on price, payment method and manufacturing period.
Only small manufacturing units are afraid of losing the order and agree to any requirements, but once the contract is signed and the advance payment is paid, it is likely to break the contract, so they don’t care about integrity!
Please follow the above six points and be sure to choose a reliable hydraulic press manufacturer.