SPLIT PACKAGE SEAL FOR LARGE SIZE PRESS

Scenario

In companies that use large presses, such as in forges and steel mills, it is important to have seals that can be replaced during maintenance even without having to completely disassemble the machine. These types of presses work with very high pressures and can have seats with specific non-standard dimensions with the need to size the sealing system in a customized way.

Challenge

One of our customers, an important forge company, specialized in the casting of large parts, asked us to create a seal for high pressure fluid used to move the press itself to replace the original spare parts that the customer complains of being short-lived. The seal must be housed inside existing seats as it is a maintenance. The reliability of the seal is an indispensable factor given the costs of any production stops linked to the long time required for disassembly and replacement of the same.

Solution

ATP has a tradition of over 45 years in the field of seals and plastic and elastomeric materials sector producing in addition to turning large seals for industrial automations where, as in this case, reliability is not a questionable parameter.

The ATP technical team started with a joint analysis with the customer where the operating conditions were defined:

• Liquid in contact: water containing a low percentage of anti-corrosive solution
• Pressure: 200 BAR
• Stroke: 2000 mm
• Environmental temperature
• Speed: 0.1m / s
• Sealing diameter: Ø 800 mm

The seal previously used by the client was a pack consists of 3 sealing central rings made of PTFE which ensured a low coefficient of friction but with a low resistance to abrasion. The high pressure in fact generates a strong load on the seal that under dynamic conditions undergoes an important abrasion phenomenon. The choice of material for the new seal was then conditioned both by the need to have a low friction coefficient with the characteristics of anti-sticking, which has a high resistant to abrasion generated by the strong friction derived from the loads on the gasket during the movement of the same. The material chosen as most suitable for the 3 central elements was SINTEK HTPU.

For external elements, which essentially perform a static support function for the central rings, it has been chosen instead of a plastic material, the EKOGLIS S-AL, with excellent characteristics of resistance to the loads.

Later, when the seal begins to wear, it will be possible, with a system of screws, to reduce the height of the seat, obtaining an increase in the specific load on the seal, thus allowing to obtain an extension of the life cycle of the same.

A “Z” cut has been made on all the details, applied with a special punch that allows the seals to be mounted directly on the press without the need to disassemble it, reducing the leakage associated with the cut itself.

Testimony

“The seal is mounted easily and sealing is very good, considering the cuts on the seal” User Product.

Consult our general catalog for the recommended materials depending on the operating conditions.