29-06-2012, 05:27 PM
LATHE OPERATIONS
LATHE OPERATIONS.pdf (Size: 2.65 MB / Downloads: 75)
Introduction
Lathes were developed as early as the 15th century and were known as "bow"
lathes. The operator rotated the workpiece by drawing a bow back and forth,
either by hand or with the use of a foot treadle. Next came Bessons lathe
in 1568, which was driven by a cord passing over a pulley above the machine.
This in turn drove two other pulleys on the same shaft which rotated the
workpiece and a crude, wooden lead screw, which in turn allowed the operator
to remove metal from the piece being machined. The screw cutting lathe
originates in the 17th century. Development and advancements have continued
and today we have sophisticated computerized controlled lathes.
Lathes Types and Uses.
a. General. The lathe is a machine tool used principally for shaping
articles of metal, wood, or other material. All lathes, except the vertical
turret type, have one thing in common for all usual machining operations;
the workpiece is held and rotated around a horizontal axis while being
formed to size and shape by a cutting tool. The cutter bit is held either
by hand or by a mechanical holder, then applied to the workpiece. Principal
capabilities of the lathe are forming straight, tapered, or irregularly
outlined cylinders, facing or radial turning cylindrical sections, cutting
screw threads, and boring or enlarging internal diameters. The typical
lathe provides a variety of rotating speeds and suitable manual and
automatic controls for moving the cutting tool.
Conclusion
This task described the various threads, forms, uses, calculations, and
machining techniques. This information will assist you in your future role
in the metalworking field.