saramax

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SARAMAX clamping system

SARAMAX is a mechanical clamping system which makes it possible to produce high wear resistant combirolls for conventional intermediate stands of wire and bar mills or for finishing stands of rod and bar mills.

The lateral clamping force induces an axial compression stress in the SARAMAX, SARACOM or SARAMET roll rings which are mounted on the shaft.
When transmitting higher rolling torques, the lateral friction force is supported by keyways and wedges on the lateral face or inside the rings or by additional hot shrinking of the rings on the shaft.

Manufacturing

The clamping system SARAMAX consists of a tough roll shaft and a locking device allowing to fix the wear resistant roll rings.
Considering the sizes of the stands, the rolling forces, the rolling speed, the roll stock and the groove profiles, Saar-Hartmetall und Werkzeuge GmbH makes the following recommendations in agreement with the rollers concerning:

the roll shaft material; for single strand rolling and rolling forces below 20t, spheriodal or cast iron roll shafts should be used, for multiple strand rolling and rolling forces above 20t, forged steel shafts are a better choice.

the transmission of the rolling torque; for round grooves up to 20mm and oval grooves with a width of up 32mm, axial clamping with lateral friction is sufficient. Round grooves from 20-30mm and ovals from 32-44mm require a lateral friction force together with lateral round or 10-15mm deep wedges in the roll rings. Roll rings with bigger grooves are mounted using the lateral friction force and large keyways and wedges in the steel part of the SARACOM or SARAMET rings.

the material of the roll rings; SARAMET rings should be used at rolling speeds from 0.2-15 m/sec, SARAMANT or SARACOM roll rings with a hardness of 600-700 HV30 are mounted for speeds from 2-15 m/sec and with a hardness of 700-800 HV30 for speeds of 4-30 m/sec.

The roll shafts are supplied in a rough turned condition by the customer or they are fully machined by Saar-Hartmetall und Werkzeuge GmbH. After the grinding of the roll ring seat area on the shaft and the manufacturing of all the necessary locking devices, the SARAMAX clamping system is mounted.
The grooves are machined either on our customers' lathes or they are ground or turned to tight round tolerances with our own machines.

Applications

Depending on the dimensions and the roll stock, a performance of 2000-15000 tons per groove at a redressing rate of 1-2mm of the diameter is possible when using the SARAMAX clamping system. Efficient cooling immediately after the contact with the hot material and correct redressing of the rolls are absolutely necessary.

Advantages of the SARAMAX-system

very easy to mount and to dismount

possibility to reuse worn cast iron rolls

favourable axial pre-compression stress in the wear resistant roll rings

transmission of the rolling torque by friction, additional fixing with keyways and wedges is possible

protection of the fragile roll material by lateral steel rings

tight tolerances of the groove roundness, as the roll rings remain on the shaft while being redressed

possibility to check and to correct the roundness after rolling incidents