Archive for Reverse Tonnage

Shock Dampers for Snap Through

Stamping PressShock dampers are one of the best kept secrets of the metal stamping industry. Many people have heard of them but most do not realize the positive effect they can have on a die or press.

At the instant of breakthrough during blanking operation, the presses and dies are subjected to severe loads, commonly referred to as snap-through force. This eventually results in damage to the bearings, seals, gibways and increased die wear. With the Hylatechnik Blanking Stroke Dampers, the life of the press and dies is extended. In addition, noise and vibration are significantly reduced.

How Do Shock Dampers Work?

Essentially the dampers are a set of oil-filled cylinders set beneath the ram. The cylinders are set to contact the ram or slide just prior to punch with the material. The oil in the cylinders is forced through an orifice designed to limit ram speed to normal velocity while providing little additional force on the press drive. The rapid and damaging acceleration/deceleration that can occur at the instant of punch break through is dampened by the orifice controlled speed of the cylinder.

Below is data from an actual demonstration of the Hylatechnik Damper at a customer’s facility:

400 Ton Press @ 32 s.p.m. Without Hylatechnik Shock Dampers

1st Stroke:
Working tonnage – 362 tons
Reverse tonnage – 125 tons, 31%

2nd Stroke:
Working tonnage – 362 tons
Reverse tonnage – 129 tons, 32%

With Hylatechnik Shock Dampers

1st Stroke:
Working tonnage – 379 tons
Reverse tonnage – 3 tons, 0.75%

2nd Stroke:
Working tonnage – 379 tons
Reverse tonnage – 3 tons, 0.75%

Shock dampers may make a surprising positive difference on your press. Call 877-423-5843 to schedule a Hylatechnik Shock Damper demonstration on a heavy snap-through application.

Case Study: SKD Automotive Group | Hylatechnik Shock Dampers

HylatechnikFounded in 1937 and based in Troy, Michigan, SKD Automotive Group manufactures and supplies metal stampings, components, and weldments to the automotive industry in North America.

SKG Automotive Group assessed the effectiveness of Hylatechnik shock dampers on a 1600 Ton Verson Press.

Vibration measurements were conducted on the press frame and on grade near the press with and without four Hylatechnik SHYC-100-15 Blanking Stroke Shock Dampers mounted on the bolster plate. The dampers have a capacity of 100 tons and a stroke of 15 mm. At the time of testing the press was producing Ford 944/5 Blades from material nominally 0.154” thick.

The measurements of the time signal and frequency spectrum of acceleration were measured on the frame of the press and the floor in front of the press, first without the dampers in place and then with the dampers in place. Without the dampers, the press was achieving a tonnage of 1050, whereas the press was achieving a tonnage of 1200 when the dampers were in place.

The results show that the Hylatechnik dampers provided an improvement in the vibration levels occurring on the press frame and transmitted to the surrounding ground. The dampers were found to reduce vibration levels by approximately 40%.

Hylatechnik Shock Dampers are designed to protect the press and tooling from snap-through loads. The Hylatechnik dampers will reduce or eliminate: reverse loads, floor vibration and noise and can also significantly increase tool life. Applications include: hydraulic presses, mechanical presses and press breaks. The shock dampers are not limited to the press size.

Read more about how to reduce reverse tonnage with the use of shock dampers.

Reverse tonnage a problem? Call 1-877-ICFLUID to schedule a demo of Hylatechnik shock dampers.

Reverse Tonnage Reduction with the Use of Shock Dampers

Reverse Tonnage Shock DampersHydraulic shock dampers can be beneficial to reduce the effects that come from reverse tonnage. This device can reduce wear and damage and keep presses working more efficiently and with fewer problems.

The Signs of Reverse Tonnage Problems

Reverse tonnage issues show up over time with many signals. Failure of slide connection area press components can indicate negative tonnage problems. Problems with other frame parts or premature wear of punches and dies can also imply issues with tonnage.  Here are some more indicators:

  • Loose air and hydraulic lines
  • Leaking air and hydraulic lines
  • Electrical problems
  • Foundation issues
  • Extreme high levels of noise

A shock damper can reduce the effects of negative tonnage to prevent these symptoms from occurring. Reverse tonnage is typically seen in blanking applications and cutting and perforating applications.

The press frame will see tension and compression loads with each stroke of the press. If these loads exceed the designed elastic limits of the press, the press frame will be damaged. This type of damage will occur with the excess of forward or reverse tonnage. Cracks can occur in the components, including the slide, crown, drive linkage, and housings. The first indication of problems begins with the most vulnerable parts, including hydraulic lines and bolts. The damage can then progress to other areas. However, a shock damper can absorb those forces to prevent the effects to the presses.

With the right hydraulic shock absorber, smaller presses can handle heavier loads and improve their productivity. Other benefits of choosing the right shock damper for your presses include:

  • Reduce maintenance costs
  • Reduce stresses on the press along with the tooling and foundation
  • Increase die life
  • Improve part quality
  • Reduce noise of operation

The Benefits of Using a Shock Damper

Though you have several solutions to reducing the effects of reverse tonnage to your presses, a hydraulic shock damper is the most versatile option. It is cost efficient and can be retrofitted to work with used presses. It absorbs the shock without reducing the capacity of the press and only adds minor forward tonnage to the job.

Another benefit that you may not think of is that a shock damper can provide better ergonomics for the operator by reducing vibrations which cause stress to the lower parts of the body. It can reduce the physical fatigue that is often felt after several hours of work.

How Do They Work?

The shock damper is designed to limit the slide speed after material breakthrough. This allows more blanking capacity for each press that uses the hydraulic shock damper system. 

A hydraulic shock damper can extend the life of your press by protecting it from damage due to reverse tonnage. This is a cost effective way to protect your equipment and help it work more efficiently.

Read how Hylatechnik shock dampers reduced reverse tonnage by 40%.

Reverse tonnage a problem? Call 1-877-ICFLUID to schedule a demo of Hylatechnik shock dampers.