Stretching system (Stretcher) provides the necessary tension to Fabric with a controlled movement of a roll called tension roll. Keeping constant tension means:
- paper quality optimization;
- sheet break reduction;
- increased Fabric life;
- avoid Fabric overstretching;
- avoid drive roll slippage.
Stretcher is also in charge of long stroke roll displacement during Fabric change operations. WIRE ARMS STRETCHERS, with rotational movement. Tension roll moves through arms operated by air rides or pneumatic cylinders. Wire tension is proportional to air pressure. Pneumatic system allows continuous tension compensation.
FELT STRETCHER FOR PRESS OR DRY END, with linear movement of tension roll support carriages. We can propose different stretcher designs: SCREW JACK STRETCHER, where carriages move driven by a rotating screw jack system; PNEUMATIC COMPENSATED SCREW JACK STRETCHER where a couple of air cylinders keep constant tension. Tension roll stroke is adapted to Wire/Felt length and to available room.
Models with electric, hydraulic or pneumatic motor.
The simplest way to control the tension is the manual system. The operator decides the tension and stretch or slack of the Fabric by acting on the pushbutton (in the case of motor) or adjusting the air pressure (in the case of air rides or pneumatic cylinders). Operator is then requested to measure the tension. Stretcher can be associated with a LOAD CELL, mounted on a fixed roll, which continuously detects a signal, transforms it in actual tension and sends it to a display. In the automatic control system, the Load Cell sends the signal to a regulator which adjusts roll position to match pre-set tension value.