| 摘要 |
<p>Rigid and preformed pipes are measured to determine lengths in order to produce an exact replacement. Measurements are made by sliding a cylindrical tape down pipe and a movable index remaining in place when tape is removed provides measurement. A container for measuring tape (c) comprises a pair of opposing concentric drums (A, B) one of which is fixed (A) while the other (B) is free to rotate. Tape passes through opening (D) into housing (6) in rotating drum (B). A sliding index (F) on tape is locked by a screw when end is passed into tube being measured. Distance from tap end to index face gives required measurement.</p> |
