| 摘要 |
<p>A power operated tube expander apparatus having automatic step control for deep hole rolling of a tube to a header sheet. A stop collar in the form of a thrust assembly is supported on the cage behind the expander rollers to prevent movement of the cage inward of the tube during the expansion operation. After rolling a longitudinal segment of tube, controls are operable to displaceably step the collar a predetermined incremental distance longitudinally away from the expander end. This allows an additional segment of tube to be subsequently rolled. Stepping of the collar continues until completing total joinder of the tube to the header.</p> |
