how to adjust the rollers of the roll forming machine

Why spacers are used in roll forming machines?

The spacers and shims are part of the roll set. At each shaft, the total lengths of the rolls, spacers, and shims are equal to the roll space.
The difference between a spacer and a shim relates to their length, application, and method of manufacturing.
Spacers are long, usually between 4 to 150 mm. The spacers are an integral part of the roll-forming set. Shims are thin, usually 0.025 to 2.5 mm. The use of shims should be avoided wherever possible. The total length of the rolls is dictated by good design practice. The difference between the available roll
space and the roll length fill with less expensive spacers. Spacers are usually manufactured from seamless carbon steel tubes.

Spacer change for muti-profile roll forming machine

The most frequently used standard spacers are made out of one piece as :
Split Spacers:
Split spacers can reduce roll changeover time of multiple width sections. Instead of removing the nuts from the end of the shafts, pulling off the stands, rolls, and spacers, it can be sufficient to loosen the nuts and pull the operator-side stand out by approximately (6 to 20 mm).
The gap will allow the removal of the split spacers and the replacement of them into new locations. This method can reduce roll change time by about 70 to 80%. For example, 10 to 24 min per pass changeover using standard spacers can be reduced to 3 to 5 min with non-split spacers, depending on the size of the mill, number of rolls, and the experience of the operator.

Roll Forming Machine Part-Spacers and Shims

Horseshoe Spacers:
Horseshoe spacers were among the first quick removal spacers developed by the industry. This type of spacers, as well as the horseshoe shims, create considerable problems. The “open” sections of all horseshoe spacers are in the same direction. In the case of small shaft diameters (1 to 1.5 in), the forces applied by overtightening the nuts at the end of the shafts can bend the shafts. The continuous flexing of the shafts at each revolution can create another problem. The top roll spacers (and the shims) can fall out and damage the next pass rolls. Therefore, manufacturers use spring-loaded ball locators to hold the horseshoe spacers in position. However, it is highly recommended not to use horseshoe spacers at all.

Bolted and Hinged Split Spacers:
Bolted spacers have been used to avoid accidental falling of spacers from the shafts. These spacers will not fall out but the removal of the screws or other fasteners takes too much time. Hinged spacers somewhat reduce the time required to remove and install these bolted-type spacers.

Boltless Spacers:
A variety of boltless, quick removal spacers has been developed and successfully used. The removal and reinstallation of such split spacers may take less than 1 min after the operator-side stand is pulled out by a short distance.
Split spacers are more expensive than one-piece spacers, but the extra cost can be quickly recovered by reducing the nonproductive time.