Transfer Press Line

We manufacture Transfer Press Line. Deep drawing process & Deep drawing press & Double action deep drawing press & Triple action deep drawing press

In the midst of the changing global economic conditions in recent years, the automotive industry has found itself in an environment where together very high expectations (in terms of enhanced product competitiveness in response to the demand for even lower costs, even more, design advances, higher quality, and improved environmental performance) the production systems themselves have also been enhanced because of the shift from large lot production to diversified lot production and the demand for lower energy usage and material usage during production, and production has thus diversified to the point where it has even been evolving in response to
environmental issues.

In terms of its production of automotive body parts using presses, our customer was using conventional transfer and tandem press lines composed of mechanical presses and this resulted in major technological constraints in the production of such parts. Moreover, after considering future difficulties with accommodating major technological
advances and future customer requirements and also its desire to reduce the high energy consumption required for production, our customer decided that it was necessary to revolutionize its press line production systems using next-generation technologies.

Accordingly, the development of a next-generation press production system was initiated in 2005 with the aim of achieving an overwhelming competitive advantage that could serve as a global benchmark for
the next 30 years and enable both the ultimate pursuit of production efficiency and the accommodation of evolutionary changes in its products.

The press line that resulted from this development is a tandem press line composed of 4 servo presses and servo feeders (conveyance equipment that moves panels from one process to the next). Though one of
the goals of using servo technology in its equipment were to improve cycle times via the synchronized control of the presses and associated conveyance equipment and allow the differentially-phased operation of the presses, the primary goal was to optimize the press forming conditions and the panel conveyance conditions for each product.

On conventional press lines, the slide motion of each press in the line is almost uniform, and each parameter is optimized in order to attain the maximum formability characteristics of the press, the maximum flexibility of the conveyance equipment, and the maximum conveyance speed.

This new press line has allowed the achievement of both deep draw-forming which was not possible using conventional methods and the world’s highest level of productivity. The following provides an overview of the development technologies used to make this new system a reality.

Transfer Press Line

A transfer press line is a specialized production line that utilizes a series of synchronized transfer presses to perform multiple forming operations on a workpiece in a continuous sequence. This streamlined process enables the efficient and precise production of high-volume, complex metal components.

Key Components of a Transfer Press Line:

1. Uncoiler: The uncoiler unwinds the coil of metal stock, typically steel or aluminum, feeding it into the first transfer press.
2. Straightener: The straightener removes any curvature or warping from the metal strip, ensuring a consistent feeding process.
3. Feeder: The feeder precisely positions the metal strip at the entrance of the first transfer press.
4. Transfer Presses: Each transfer press in the line performs a specific forming operation, such as blanking, trimming, drawing, or stamping.
5. Transfer System: A transfer system, consisting of grippers or arms, moves the partially formed workpiece between the transfer presses, ensuring precise alignment and positioning.
6. Ejector: The ejector removes the finished part from the last transfer press and deposits it onto a conveyor belt or collection bin.

Working Principle of a Transfer Press Line:

1. Metal Uncoiling and Straightening: The metal coil is unwound and straightened, ensuring a flat and consistent strip for feeding.
2. Blanking and Trimming: The first transfer press blanks the desired shape from the metal strip and trims away excess material.
3. Transferring the Blank: The transfer system moves the blanked part to the next transfer press for further forming.
4. Drawing and Stamping: Subsequent transfer presses perform various forming operations, such as drawing, stamping, or flanging, to create the desired shape of the workpiece.
5. Ejection and Collection: The finished part is ejected from the last transfer press and collected onto a conveyor belt or bin.

Advantages of Using a Transfer Press Line:

1. High Productivity: The continuous sequence of forming operations significantly increases production rates.
2. Reduced Labor Costs: Automated transfer presses minimize labor requirements and improve overall efficiency.
3. Consistent Quality: Synchronized presses and precise transfer systems ensure consistent and high-quality parts.
4. Complex Shape Capability: Multiple transfer presses allow for the production of intricate and complex components.
5. Material Savings: Optimized blank sizes and minimal waste reduce material consumption.

Applications of Transfer Press Lines:

Transfer press lines are widely used in various industries, including:

1. Automotive Industry: Producing car body panels, fenders, hoods, and other automotive components.
2. Appliance Industry: Manufacturing cooking pots, pans, sinks, and other appliance components.
3. Aerospace Industry: Creating aircraft components, such as fuel tanks, fuselage sections, and engine housings.
4. Electrical Industry: Producing electrical enclosures, housings, and components.
5. Medical Device Manufacturing: Manufacturing medical implants, surgical tools, and other medical devices.

Conclusion:

Transfer press lines represent a sophisticated approach to high-volume metalforming, offering exceptional productivity, consistent quality, and the ability to produce complex shapes. Their versatility and efficiency make them essential tools in modern manufacturing, particularly for industries that require the production of high-quality, complex metal components.

The Primary Goals of a Transfer Press Line

The primary goals during the development stage of the servo press forming machines were the ability to perform deep draw-forming and to achieve high press stroking speeds (27 SPM when running in Continuous
mode).

First, a slide stroke length of 1100 mm was selected to accommodate the deep draw-forming target values. An eccentric crank motion system was adopted for the slide drive mechanism because of the importance of high slide speed during the forming portion of the press stroke, especially in the vicinity of the bottom dead center. The slide of this long-stroke press is driven at high speed, and rapid acceleration and
deceleration is also achieved via the servo controls.

Compared with a link mechanism, the eccentric crank mechanism design is simpler, which also simplifies the motion controls. On the other hand, a great deal of torque is required to drive such a press and to attain the requisite forming tonnage, and thus it was necessary to develop a low-speed, high-torque servo motor for these large-capacity servo presses.

The servo motors for this development project (Photograph 2) were manufactured by the press machinery manufacturer EMS Metalworking Machinery, using its independently developed technologies. Based on the specification requirements provided by our customer, EMS Metalworking Machinery optimized the structural designs, the magnetic circuit designs, the cooling architecture, and the CNC controls of its servo motors

This resulted in the achievement of unique large-capacity servo presses (Photograph 3) that operate at high speeds with high accuracy. Additionally, the highest capacity draw-forming press (23000 kN
rated capacity) in the line is powered by 4 servo motors, and it also contributes to a smaller installation footprint and lower equipment investment costs.

Servo Motors in a Transfer Press Line

At the same time, in order to achieve the targeted deep draw-forming requirements, high-precision variable controls were also necessary for the die cushion pressure to enable it to track with the press motion. The die cushion equipment used in the draw-forming press in this new line utilizes a hybrid motorized hydraulic system equipped with NC controls.

Small high-speed servo motors are used to control the pressure inside hydraulic cylinders to enable high responsiveness to die cushion pressure fluctuations during the forming portion of the press stroke and high-precision pressure controls that are within ± 2.5% of the commanded pressure value. Additionally, the electrical power regeneration feature in the die cushion enables 70% of the working force to be recaptured, which also helps to lower energy consumption.

In order to achieve the targeted line SPM, the ability to complete a 5~6 meter conveyance stroke within 1.5 seconds was required. However, it would be difficult to achieve this requirement using a simple sliding-type
the mechanism, and as a consequence, it was necessary to combine a long arm with a swiveling pivot shaft. The drive method for the arm is based on the well-known Scott Russell linear linkage, and it has a newly developed link mechanism that enables motion in the lift direction by replacing the connection point between the feed arm and the drive arm with a short linkage.

Transfer Press Line Manufacturer

In the case of a conventional Scott Russell linkage, it is customary
to raise the entire unit in order to achieve motion in the lift direction, which means that as the conveyance distance lengthens the unit as a whole becomes larger and larger. However, this newly developed mechanism
does not require the lifting of the entire unit–the additional short linkage only needs to be actuated–and this is extremely advantageous for the high-speed motion required for tandem lines.

Additionally, because the linkage in the linear direction is achieved by controlling 2 axes on one side plus 1 tilt axis, even when multiple conveyance equipment units are connected the total number of controlled axes can be kept to a minimum. This press-to-press conveyance equipment was the result of a joint development project with EMS Metalworking Machinery.

A comprehensive control system is crucial to achieving high-speed synchronous control of the entire press line, and a priority has been placed on selecting systems based on their synchronization control performance with respect to the servo press machines. In order to derive the maximum benefit from the high-speed, high-accuracy control of the position of the servo press slide throughout its entire motion range from top dead center to bottom dead center, this synchronized control system not only provides synchronized controllability of the conveyance equipment it also constantly monitors its positional relationship with the press slide.

It is also equipped with interference prevention features to deal with a wide variety of possible risks. Moreover, the conveyance equipment drive mechanism incorporates know-how obtained during the development of the servo presses, and just like a servo press it uses a low-speed, high-torque servo motor in combination with a gear drive system to achieve the power performance required for high-speed operations.

Especially in the case of the above-mentioned link drive mechanism, the drive power is transmitted internally via the swivel arm, which enables motors and other heavy items to be mounted in a stationary position, which enables the feed arms and drive arms to swivel at high speed. The body panel conveyance system incorporates the high-speed conveyance configurations used on transfer press lines, i.e., a crossbar cup feed system.

Transfer Press Line Parts

The end of the feed arm is equipped with a tilt feature that swivels in the vicinity of the crossbar center axis and a tool section mounted on the crossbar is used to handle the other swiveling and/or shifting motions required in the vicinity of the axis.

Optimized press forming conditions are required in order to maximally leverage the capabilities of a servo press and to achieve the goal of deep draw-forming. Formability is improved by optimizing the press speed during the forming portion of the stroke by controlling the speed of the press slide and by optimizing the material flow characteristics by controlling the die cushion pressure （Figure 2） shows the target deep draw-forming values and the degree to which each parameter contributes to the final result

However, based on prior tests, we knew that the forming conditions required to achieve deep draw-forming that was 50 mm deeper than
conventional techniques were only found in an extremely narrow range, and additionally, we knew that the forming conditions varied depending on the shape of the part being formed.

The most rudimentary method for finding optimal forming condition solutions is to actually manufacture dies and then perform forming trials under various conditions, but this involves a tremendous amount of time and expense. Moreover, when forming automotive body parts and especially when deciding upon the design of exterior body panels.

It is necessary to ascertain whether forming is possible or not at a very early stage in the development process, and it was a real problem because it is not possible at that early stage to determine whether such forming would be possible through a trial and error process that uses dies. In this development project, press forming simulations were used instead of trial and error testing in order to develop a system that would deliver optimal forming conditions.

Press Forming with a Transfer Press Line

Press forming simulations are analyzed and the results are evaluated by dividing the press forming process into a number of discrete stages and then using optimization software to fine-tune the press forming speed parameters and the die cushion pressure parameters at each stage. Based on the final analysis results of the minimum primary strain and the results of the material thickness reduction rate, the optimal forming conditions are determined by selecting a central value within a range that has a good balance between both factors, and then the servo press motion controls and the die cushion pressure controls are converted into data.

However, in existing press forming simulation software, the analysis function assumes that the relationship between the material stress and strain and the frictional coefficients are always uniform, and thus there were problems because even when the forming speeds were changed in the simulation software the resulting analysis results remained the same. As such, we also developed the servo press forming simulation software used for this system.

When simulating the speed-dependent relationship between material stress and strain, the relative speed of the adjacent contact points of the forming model during the forming process was calculated, and that was used as the strain speed, and a module was added that varies the relationship between stress and strain depending on this calculated strain speed. And a method was also incorporated for the frictional coefficient that correctly simulated the effects of relative speed and contact surface pressure.

This resulted in a press forming simulation that would correctly output the forming results based on variations made to each of the forming parameters. This system enables us to determine during an early stage of new automobile development whether a design that approaches the maximum capabilities of a servo press can be used or not, and it allows the press forming conditions for each part to be automatically set during the production preparation stage.

Hydraulic presses are powerful machines used to apply a significant amount of force to an object through hydraulic fluid pressure. They are essential in various industrial applications, providing the necessary force for processes such as metal forming, stamping, bending, and molding. The versatility and efficiency of hydraulic presses make them indispensable tools in manufacturing and production lines. This document will explore the different types of hydraulic presses, their application areas, components, operational principles, manufacturing process, and the challenges and advancements in the industry.

Types of Hydraulic Presses

Hydraulic presses come in various designs, each suited to specific applications and requirements. The primary types of hydraulic presses include C-frame presses, H-frame presses, four-column presses, straightening presses, arbor presses, laminating presses, and transfer presses.

C-frame presses, also known as gap-frame presses, have a C-shaped frame that provides three-sided access to the work area. This design is ideal for applications requiring easy loading and unloading of materials.

H-frame presses, or two-post presses, have a robust H-shaped frame that offers excellent stability and strength. They are commonly used for heavy-duty tasks such as metal forming and straightening.

Four-column presses, or four-post presses, have four vertical columns that provide superior support and uniform force distribution. These presses are suitable for large-scale applications requiring high precision and repeatability.

Straightening presses are specialized hydraulic presses used to straighten bent or distorted metal components. They are widely used in the automotive and construction industries.

Arbor presses are smaller, manually operated hydraulic presses used for light-duty tasks such as assembly, riveting, and broaching. They are commonly found in workshops and small manufacturing facilities.

Laminating presses are used to bond multiple layers of material together under heat and pressure. These presses are essential in industries such as electronics, where laminated components are common.

Transfer presses are automated hydraulic presses that move the workpiece through multiple stations for different operations. They are highly efficient and used in high-volume production environments.

Application Areas

Hydraulic presses are employed in various industries, thanks to their ability to deliver consistent and precise force. Key application areas include:

Metal forming and forging: Hydraulic presses are crucial in shaping and forming metal parts through processes such as stamping, bending, and deep drawing. They are essential in the production of automotive parts, machinery components, and structural elements.

Automotive industry: In the automotive sector, hydraulic presses are used for manufacturing various parts, including body panels, chassis components, and engine parts. They play a critical role in ensuring the structural integrity and performance of vehicles.

Aerospace industry: The aerospace industry relies on hydraulic presses for forming and shaping high-strength materials used in aircraft components. Precision and reliability are paramount in this industry, making hydraulic presses indispensable.

Plastic and rubber molding: Hydraulic presses are used in the molding of plastic and rubber components, including automotive parts, household goods, and medical devices. They ensure consistent product quality and precision.

Electrical and electronics industry: In the electronics sector, hydraulic presses are used for laminating circuit boards, forming connectors, and assembling electronic components. They provide the necessary force and precision for delicate operations.

Medical device manufacturing: Hydraulic presses are used in the production of medical devices, including surgical instruments, implants, and diagnostic equipment. They ensure the high precision and quality required in the medical field.

Packaging industry: Hydraulic presses are employed in the packaging industry for forming and shaping packaging materials, such as cardboard, plastic, and metal. They help produce packaging solutions that are strong, durable, and aesthetically pleasing.

Components of a Hydraulic Press

A hydraulic press comprises several key components that work together to generate and control the applied force. The main components include the frame, hydraulic cylinder, hydraulic pump, control valves, hydraulic fluid, pressure gauges and sensors, and die and tooling.

The frame is the main structure of the hydraulic press, providing stability and support for all other components. It is typically made of high-strength steel to withstand the significant forces generated during operation.

The hydraulic cylinder is the core component that generates the pressing force. It consists of a cylindrical chamber, a piston, and a piston rod. When hydraulic fluid is pumped into the cylinder, it moves the piston, which in turn applies force to the workpiece.

The hydraulic pump is responsible for generating the hydraulic fluid pressure needed to move the piston. It draws hydraulic fluid from a reservoir and delivers it to the cylinder under high pressure.

Control valves regulate the flow of hydraulic fluid to and from the cylinder, controlling the movement and force of the press. These valves can be manually operated or automated, depending on the press design.

Hydraulic fluid, typically oil, is the medium through which force is transmitted in the hydraulic system. It must have suitable properties, such as viscosity and lubricity, to ensure efficient operation and protect system components.

Pressure gauges and sensors monitor the hydraulic fluid pressure within the system. They provide real-time feedback to the operator or control system, ensuring safe and accurate press operation.

Die and tooling are the interchangeable components that come into direct contact with the workpiece. They are designed to shape, form, or cut the material as required by the specific application.

How Hydraulic Presses Work

Hydraulic presses operate based on Pascal’s principle, which states that pressure applied to a confined fluid is transmitted equally in all directions. This principle allows hydraulic presses to generate significant force with relatively small input pressure.

The operation of a hydraulic press begins with the hydraulic pump drawing fluid from the reservoir and delivering it to the cylinder. The control valves regulate the flow of fluid, directing it into the cylinder to move the piston. As the piston moves, it applies force to the workpiece placed between the die and tooling.

The hydraulic fluid plays a crucial role in this process, as it transmits the applied pressure and lubricates the system components. The pressure gauges and sensors continuously monitor the fluid pressure, providing feedback to ensure the press operates within safe limits.

The force generated by the hydraulic press can be precisely controlled by adjusting the hydraulic fluid pressure and the position of the control valves. This allows for accurate and repeatable operations, essential for high-quality manufacturing.

Manufacturing of Hydraulic Presses

The manufacturing of hydraulic presses involves several stages, from design and engineering to assembly and quality control. Each stage is critical to ensuring the press’s performance, reliability, and safety.

Design and engineering: The process begins with the design and engineering phase, where specifications for the press are developed based on the intended application. This includes selecting suitable materials, determining the required force and stroke, and designing the frame and hydraulic system.

Material selection: High-quality materials, such as high-strength steel for the frame and durable alloys for the hydraulic components, are selected to ensure the press’s longevity and performance.

Fabrication of components: The individual components of the hydraulic press, including the frame, cylinder, and pump, are fabricated using precision machining and manufacturing techniques. This ensures that each component meets the required tolerances and specifications.

Assembly process: The fabricated components are then assembled into the complete hydraulic press. This involves mounting the cylinder, pump, and control valves onto the frame, connecting the hydraulic lines, and installing the die and tooling.

Quality control and testing: Rigorous quality control measures are implemented throughout the manufacturing process to ensure the press meets all specifications and standards. This includes pressure testing the hydraulic system, verifying the accuracy of the control valves, and performing operational tests to ensure the press functions correctly.

Advancements and Innovations

The hydraulic press industry is continually evolving, driven by advancements in technology and increasing demands for efficiency and precision. Key innovations include automation and control systems, energy efficiency improvements, and smart hydraulic presses.

Automation and control systems: Modern hydraulic presses are often equipped with advanced control systems that automate the pressing process. This includes programmable logic controllers (PLCs), human-machine interfaces (HMIs), and sensors that monitor and adjust the press’s operation in real time. Automation improves efficiency, reduces the risk of human error, and enhances the consistency of the finished products.

Energy efficiency improvements: Manufacturers are focusing on developing hydraulic presses that consume less energy and have a smaller environmental footprint. This includes using variable displacement pumps, energy recovery systems, and optimizing the hydraulic system’s design to minimize energy losses.

Smart hydraulic presses: The integration of IoT (Internet of Things) technology into hydraulic presses has led to the development of smart presses. These presses can communicate with other machines and systems, providing real-time data on their status, performance, and maintenance needs. This connectivity allows for predictive maintenance, reducing downtime and extending the press’s lifespan.

Challenges in Hydraulic Press Manufacturing

The manufacturing of hydraulic presses presents several challenges, including precision and quality requirements, cost management, technological advancements, and environmental considerations.

Precision and quality requirements: Hydraulic presses must deliver consistent and precise force, which requires high levels of accuracy in the manufacturing process. Ensuring each component meets the required tolerances and specifications is critical to the press’s performance and reliability.

Cost management: The cost of materials, labor, and energy can significantly impact the overall cost of manufacturing hydraulic presses. Manufacturers must balance quality and cost to remain competitive in the market.

Technological advancements: Keeping up with technological advancements is essential for manufacturers to meet the evolving demands of the industry. This requires continuous investment in research and development to incorporate new technologies and improve existing designs.

Environmental considerations: Environmental regulations and sustainability concerns are increasingly important in hydraulic press manufacturing. Manufacturers must develop eco-friendly presses that consume less energy, use recyclable materials, and minimize their environmental impact.

Conclusion

Hydraulic presses are essential machines in various industries, providing the necessary force for processes such as metal forming, stamping, and molding. Understanding the different types of hydraulic presses, their components, and how they work is crucial for effective application and operation.

The manufacturing process of hydraulic presses involves careful design and engineering, material selection, precision fabrication, and rigorous quality control. Despite the challenges, advancements in technology and innovations are driving the industry forward, leading to more efficient, precise, and environmentally friendly hydraulic presses.

As industries continue to evolve, the hydraulic press industry must adapt and innovate to meet the demands of efficiency, precision, and sustainability. Through continuous research and development, manufacturers can enhance the performance and reliability of hydraulic presses, contributing to the success of various industrial applications.

EMS Metalworking Machinery

We design, manufacture and assembly metalworking machinery such as:

• Hydraulic transfer press
• Glass mosaic press
• Hydraulic deep drawing press
• Casting press
• Hydraulic cold forming press
• Hydroforming press
• Composite press
• Silicone rubber moulding press
• Brake pad press
• Melamine press
• SMC & BMC Press
• Labrotaroy press
• Edge cutting trimming machine
• Edge curling machine
• Trimming beading machine
• Trimming joggling machine
• Cookware production line
• Pipe bending machine
• Profile bending machine
• Bandsaw for metal
• Cylindrical welding machine
• Horizontal pres and cookware
• Kitchenware, hotelware
• Bakeware and cuttlery production machinery

as a complete line as well as an individual machine such as:

• Edge cutting trimming beading machines
• Polishing and grinding machines for pot and pans
• Hydraulic drawing presses
• Circle blanking machines
• Riveting machine
• Hole punching machines
• Press feeding machine

You can check our machinery at work at: EMS Metalworking Machinery – YouTube

Applications:

• Beading and ribbing
• Flanging
• Trimming
• Curling
• Lock-seaming
• Ribbing
• Flange-punching