Warp Alignment
Position settings for the rear guide roller dictate the path of the warp yarn from the beam to the harness eyes. Adjusting the backrest elevation alters the angle of the warp sheet as it enters the shed. Proper vertical placement ensures that the tension remains uniform across the entire width of the loom.
Process Stability
Height variations in the backrest assembly compensate for the differences in yarn elasticity between wet-spun and dry-spun linen. Maintaining a specific backrest elevation prevents the warp ends from sagging or vibrating excessively during the beat-up motion. If the roller sits too low, the bottom shed loses the necessary tautness to support the weft insertion element.
Mechanical sensors often monitor the displacement of this component to maintain a constant tension profile throughout the weaving of a full beam. The elevation adjustment is the primary tool for managing warp-wise stress.
Fabric Surface
Surface characteristics of the finished linen cloth respond directly to the geometric relationship between the backrest and the breast beam. Mill technicians use backrest elevation to create a cover factor that hides the interlacing points of the weave. A higher position generally produces a more prominent grain on the face of the fabric.
This parameter defines the physical geometry of the loom shed.
