M method for choosing the right hydraulic pressure
In the past, the term “stamping” was often confused with “bleaching”. A few years ago, mechanical and screw presses were the main tools used for stamping. However, this changed with the advent of hydraulic presses.
Hydraulic presses were first introduced in the late 1930s and have since become a common tool in forming processes such as punching, forging, riveting, stamping, shearing and crimping. Some hydraulic presses are even used for stamping and stamping.
Definition
To determine whether a hydraulic press is suitable, it is important to first understand the definitions of stamping, drawing and deep drawing.
Suppression
Molding involves cutting, shearing and drilling a board into the desired shape. The material may be a single sheet of thin sheet metal or a long continuous strip of sheet metal.
Stamping
Stamping encompasses the processes of stamping, as well as forming, bending, flanging and punching. A press that performs these processes can be called a forming press.
Deep drawing
Deep drawing involves positioning the blank in the die and using the press to stamp while the blank holder controls the flow of metal to form a cavity in the workpiece. Generally, deep drawing refers to a part whose depth of drawn or concave part exceeds half of its diameter.
Generally, mechanical presses have a simple structure and are fast and efficient, making them suitable for mass production and simple stamping and forming processes. On the other hand, hydraulic presses are better suited for small to medium batch production with just-in-time requirements, variable formats, and more stringent accuracy requirements for speed, pressure, and slider position. These presses are processed in a specific order.
Suppression
The hydraulic press is commonly used to stamp small to medium-sized parts with low production demands, typically producing 20 to 40 parts per minute. The press structure is chosen based on the size of the part, the pressure load (centralized or eccentric) and the forming mode. It can be a C-frame, double column or four column press and must be robust enough to withstand the impact and vibration of the cutting process.
A single column press with C-shaped structure may cause angular wave deformation during stamping. On the other hand, the four-column press has a tendency for the point of force action to deviate from its geometric center, while the two-column press has a stable structure, precise action and minimal deflection, making it suitable for processing with heavy loads. eccentric.
Designers often make the cutting press twice as heavy as the standard configuration to improve its stability and reduce the impact of cutting.
Optimal Use of Hydraulic Press for Blanking
The hydraulic press is ideal for the blanking process when it meets the following requirements:
- Slow production pace
The production rate is slow, with 60 strokes per minute for processing small parts (1-2 inches) and 30-40 strokes per minute for processing large parts (3-15 inches).
- Complex program settings
For a diverse range of products, a complex program setting is often required, which can be easily set with the hydraulic press.
- Frequent change of JIT parts
When frequent JIT part changes are required, the configuration can be changed quickly using a hydraulic press.
- Challenging Settings
The benefits of using a hydraulic press can be determined by knowing whether the slider travel range and pressure control adjustment meet processing requirements. When designing the press, if the stroke range is defined, a hydraulic press must be chosen. The preload of the hydraulic press is also easy to adjust, as it is used to neutralize the impact of the weight of the part or emergency stop.
- Buffer function
During feeding, when two pieces of material are fed into the die or when parts are unloaded from the die, the device may fail to eject the machined parts, resulting in the pressing of two parts. In this case, a mechanical press may be damaged, while the hydraulic press will not be damaged as it has an overload protection function that limits the maximum pressure.
S compression
Hydraulic presses are widely used in stamping processing and come in various configurations. The most commonly used settings are:
- 20-250 ton single column press (for small parts processing)
- Four-column press from 50 to 1000 tons (for processing large and medium parts)
- Double column press (for processing large parts with conveyor or eccentric pressure)
Note that there are few double column presses with working pressure above 5,000 tons.
Selection of Hydraulic Press for Stamping
The hydraulic press must be selected for stamping when the following requirements are met:
- Mixed processing of large and small parts
- High die replacement frequency and Just-In-Time requirements
Due to ease of setup, the hydraulic press can be quickly configured to meet JIT requirements and change dies frequently.
- Feeding method
The feeding method can be manual or automatic depending on the processing batch. For small batch production (less than 100,000 pieces per year), manual feeding is used, while for mass production, some or all use an automatic feeding mechanism.
- Eccentric Load
If eccentric pressure is required, a double column press should be selected.
- Lifting mechanism
If a hydraulic pad is required for material support or automatic unloading, a hydraulic press must be selected.
- High requirements for slider and pressure control
When different processing speeds or slider position control are required, with high position accuracy and sustained pressure, a hydraulic press should be selected.
- Installation flexibility
When the hydraulic press needs to be reinstalled for another project, such as when the production line changes, it can be easily restarted as maximum pressure can be used at any stage of the stroke.
Deep drawing
The hydraulic press is used for deep drawing because of its ability to precisely control the slider speed, allowing the metal material to flow without tearing during the drawing process. It is suitable for deep drawing processes with low yield, frequent die replacement, need for various drawing speeds, large hydraulic pad pressure changes and high pressure regulation requirements.
The hydraulic press is recommended for deep drawing in the following cases:
- Complex part with simplified configurations
When the part design is complex and the required processing procedures are also complex, simple adjustment of the hydraulic press is suitable for this situation.
- Press Structure
The hydraulic press can be used when a single press is required to complete processing or for multi-step drawing and modeling processes. It is also suitable for single-line production of deep drawing and/or reverse drawing and, due to its limited pressure stroke, it is suitable for finishing processing.
- Total pressure requirements
The hydraulic press can maintain the maximum pressure unchanged during the drawing process, reducing the tonnage requirements of the press.
Conclusion
When considering purchasing a hydraulic press, in addition to evaluating the factors discussed in this post such as safety, ease of maintenance, installation cycle, and cost, it is important to provide the press supplier with detailed requirements for the press's performance.
The manufacturer needs to know the following key factors: production rate, budget, mold design, part structure, number of mold changes, overall press dimensions, and the purpose of the design.
Advances in technology highlight the importance of close communication and contact with different press manufacturers to make a correct and sensible choice. Only through this communication can the correct selection and optimal use of a printer be guaranteed.
What key factors should we pay attention to when purchasing hydraulic press equipment
Hydraulic press equipment is widely used in various industries due to its high degree of automation and precision. The hydraulic system is a crucial component that determines the overall quality of the hydraulic press.
When purchasing a hydraulic press, it is important to consider all parts of the hydraulic system, including the hydraulic pump, hydraulic valve and oil cylinder, as their quality directly affects the stability of the press's performance.
The main components of the hydraulic pump station are the hydraulic pump, hydraulic valve, oil circuit block, motor and oil pipe. Any malfunction in any of these parts can seriously impact the functionality of the hydraulic press, so it is important to exercise caution when selecting this equipment to avoid careless errors.
The hydraulic pump serves as a stable source of energy. It is recommended that the pump displacement be moderate and not excessively large. If the displacement is too large, it may cause hydraulic oil that meets the requirements for equipment operation to enter the oil return pipe through the overflow valve.
This overflow will result in a loss of pressure below the specified pressure, leading to an increase in system temperature and negatively impacting equipment performance.
To avoid pressure losses in the system, it is advisable to choose the hydraulic pump wisely.
The quality of oil cylinders and molds is also crucial. High-quality components can be used for a long period of time, while low-quality components will require more frequent replacements, leading to higher costs.
It is important for users to conduct thorough research and make informed purchasing decisions. There are many manufacturers of hydraulic presses and some may compromise quality for quantity.
It is not advisable to choose a manufacturer simply because of the low price. When purchasing a hydraulic press, it is essential to prioritize quality over price to protect your own interests. It is recommended to choose carefully to ensure that you receive a hydraulic press that meets your needs and will serve you well in the long run.
When purchasing a hydraulic press, it is important to determine the specifications based on your specific needs and follow these general principles:
- Determine which part will be processed by the hydraulic press and whether there are any special requirements for the press. Consider whether there is room for growth if the scale and shape of your operations expands.
- Understand the hydraulic press process. For example, the nominal pressure of the equipment must be greater than the nominal pressure of the stamping process. For the long stroke process, it must meet not only the process strength but also the workload curve. In terms of the number of strokes, the hydraulic press must meet productivity requirements.
- The slider stroke of the hydraulic press must meet the height requirements of the workpiece. After stamping, the workpiece must be able to be removed smoothly from the die. For stretched parts, the stroke must be greater than twice the height of the parts. The dimensions of the slide block and die handle hole must be suitable for correct installation of the die.
For crank presses, the die closing height should be between the large die height and the small die height. The size of the countertop should be larger than 50-70mm (on one side) from the base of the mold for installation, and the hole diameter of the base plate should be larger than the protruding size. The size of the missing die handle must match the size of the die handle hole for the workpiece or waste.
How to correctly select hydraulic press manufacturers
Hydraulic press, as a widely used equipment in modern industry, is often evaluated based on quality, brand and price when selected by companies and institutions. The brand effect has a significant impact on price, and the same piece of equipment can have a large price difference based on the brand.
Therefore, many small and medium-sized companies prioritize cost-effective hydraulic presses, but may ignore important details in the purchasing process. Here are some points to consider when purchasing a hydraulic press.
1. Paper is
A hydraulic press is a machine made up of many parts and components.
It is unusual for hydraulic press manufacturers to produce all hydraulic press parts in-house. Instead, some parts are purchased or outsourced, with only the major components manufactured in-house and then assembled into a complete machine for sale.
Many hydraulic press users are aware of the common problem of oil leaks, which can be difficult to repair.
Attempts to correct the problem may involve a lengthy disassembly process with a low probability of success or a quick fix that may not resolve the root cause.
Is the technology of hydraulic press manufacturers not up to par, causing oil leaks? Or is it due to unreliable quality of parts, causing wear and tear and oil leaks? The latter is more likely to be the case.
The quality of the components directly impacts the quality of the hydraulic press. To ensure high-quality parts, it is recommended to choose well-known brands, even if it means paying a higher price for the hydraulic press.
When choosing a hydraulic press, you can evaluate the reasonableness of the price based on the components used. This can help eliminate concerns about potential quality issues affecting your work after purchase.
2. Configuration
The configuration of the hydraulic press is different from its components. Configuration can be categorized into high, medium, and low levels depending on the needs of various products, businesses, and organizations.
For example, a basic hydraulic press cannot compare to a fully automatic one in terms of efficiency and ease of operation.
Therefore, when selecting a hydraulic press, it is essential to understand the configuration of the equipment offered by the supplier.
The following factors directly impact the price of the hydraulic press:
- Work table size
- Maximum opening height
- number of cylinders
- Tonnage
- Other parameters
Common quotes for hydraulic presses vary.
Many manufacturers may offer low prices to attract customers, but they often increase prices during the negotiation process.
It is important to note that there may be a price difference between equipment with and without taxes, between manual and PLC-controlled equipment, and between equipment with and without molds.
Additionally, some customers may request that the manufacturer cover shipping costs, which will be calculated separately.
When choosing a hydraulic press, it is important to understand the total price offered by the supplier, including what is included and what is not included.
It is also recommended to compare prices from several companies to find the most cost-effective manufacturer.
Making direct inquiries without taking into account the specific configuration can lead to overspending and result in the selection of a less ideal option.
Tips for choosing the right hydraulic press manufacturer
Qualification Analysis
Check availability of business license, tax registration certificate, organization code, production license and quality certificate. Assess the integrity of the company's productive life, registered capital and quality supervision system.
Assess the company's production strength
Ask the company to provide photos of its processing equipment, production site, finished products and semi-finished products in production to assess their strength.
Find out about the manufacturer's sales performance
Determine whether the manufacturer has at least five years of sales contracts and has supplied large hydraulic presses, hydraulic presses and presses to military companies and listed state-owned companies.
It is generally believed that these performance indicators suggest good production capacity and quality of the company.
Technical evaluation
Analyze the technical proficiency of the equipment manufacturer's sales personnel. The business personnel of strong production companies are generally well trained, and large companies have strict requirements for their business personnel. They typically require them to have a considerable degree and proficiency before engaging in business and economic work.
Avoid blindly seeking low prices
Low-priced equipment often indicates a problem. Find out about the market price of top-tier state-owned companies. Typically, 80% of equipment prices from state-owned companies are considered the best options in terms of cost-benefit.
Analyze the sentiment of the conversation
Powerful manufacturers and business professionals are often confident and professional. For example, they may not be flexible in terms of price, payment methods and manufacturing period.
Small manufacturing units, on the other hand, may be more willing to compromise to secure an order, but once the contract is signed and advance payment is made, they may not fulfill their side of the bargain.
Therefore, it is essential to follow these six points and choose a reliable hydraulic press manufacturer.
