5 Questions with Peter Wang

Advertorial - Ask the Experts

DEES Hydraulic’s general manager discusses the advantages of hydraulic presses and technologies that can enhance machine performance.

October 3, 2019

1) What are the main advantages of hydraulic presses?

Variable speeds, stroke lengths, die spaces, and pressure force controls increase versatility. They excel at parts with deep, complex forms that require a lot of material flow. Tanks, cylinders, dish shapes – parts that require a dwell at the bottom of the stroke – are suited to hydraulic presses.

Advantages include:

  • Slide motion, position control throughout stroke length range
  • Variable slide velocity, even within single press cycle
  • Full working energy at any speed
  • Full press capacity at any point in stroke

2) Why do you recommend servo motor and accumulator technologies?

Fixed-speed induction motors draw a lot of current – as much as 30% of the press’ energy consumption at idle. Servo motors use less than 3% at idle. On presses running less than 6 strokes per minute (SPM), energy savings are about 40%. At higher than 6SPM, savings range from 25% to 30%.

Variable motor speeds allow users to form a wider range of part families by forming operations. And, servo-motor-driven presses generate less heat which means less oil during operation and lower cooling capacity requirements.

We also use hydraulic accumulators to increase pressing speed and save energy (power). It saves the energy from the pump during idle. Especially on deep-draw lengths, the accumulators save drawing time and increase SPM. A typical 100-ton press with a 37kW motor:

  • 38mm/s without accumulators
  • 200mm/s with accumulators
  • 200mm/s without accumulators would require a 200kW motor

3) What techniques does DEES use to ensure quality stamped parts?

We use 3D simulations and finite element analysis (FEA) on the press designs for rigidity analysis to prove the designs and avoid any possible errors. These tools save a lot of time on press designs and speed our time to market. Our customers get safer and stronger equipment faster, and it takes less time to prove out processes and begin production. Producers want to get their equipment running quickly so they can start making parts. Our digital design tools help us achieve high accuracy and good quality.

4) How can users improve operations once a press is installed?

Servo motors and sensors generate lots of process data. Remote assistance allows us to monitor parameters to inform customers when they may need service or adjust the program online. It can monitor data in real-time with Teamviewer which DEES can discuss with clients in an Internet chat room to understand how efficiently plants are operating.

Users can modify human-machine interface (HMI) parameters for optimum efficiency and working conditions or monitor equipment using webcams or by connecting programmable logic controllers (PLCs) directly to the Internet.

5) How does DEES support hot stamping for the higher-strength steels favored by automakers?

Hot stamping is now a popular method of strengthening alloy material, especially for car body parts. With hot stamping, speed is very important. Parts are heated up to 1,000°C before robots bring them to the die, so it’s very important to operate quickly before parts begin to cool. Once the part goes through forming, we can pump water through channels in the dies to quench the hot parts very quickly. This enhances the material properties, creating very high-strength finished parts. DEES makes hot forming tryout and production hydraulic presses ranging from 1,000 tons to 2,000 tons.

For more info: http://www.deesgroup.com.tw