摘要 |
<p>Feed device comprises a small-diameter elongate coil which extends parallel to and entire length of hot-welding bar and is set on one side of it. On opposite side is tightener to keep protective sheet under uniform tension so that sheet can leave coil, pass under hot-welding surface, to come back to tightener. Coil's support has faces under coil spaced at many points or, preferably, spaced continuously along coil's length. Faces operate on face of protective sheet and support coil by preventing it bending and are applied to sheet pressing it uniformly against hot-welding surface. Applications are hot-welded sheets. Advantages: include more resistant and uniform sheets.</p> |