An axle-bearing surface made of high carbon steel has worn beyond its useful life. When it was\nnew, the diameter was 4.00 in. In order to restore it,
An axle-bearing surface made of high carbon steel has worn beyond its useful life. When it was
\r\nnew, the diameter was 4.00 in. In order to restore it, the diameter was turned to 3.90 in to provide a
\r\nuniform surface. Next the axle was built up so that it was oversized by the deposition of a surface
\r\nweld bead, which was deposited in a spiral pattern using a single pass on a lathe. After the weld
\r\nbuildup, the axle was turned again to achieve the original diameter of 4.00 in. The weld metal
\r\ndeposited was a similar composition to the steel in the axle. The length of the bearing surface was
\r\n7.0 in. During the welding operation, the welding apparatus was attached to the tool holder, which
\r\nwas fed toward the head of the lathe as the axle rotated. The axle rotated at a speed of 4.0 rev/min.
\r\nThe weld bead height was 3/32 in above the original surface. In addition, the weld bead penetrated
\r\n1/16 in into the surface of the axle. The width of the weld bead was 0.25 in, thus the feed on the
\r\nlathe was set to 0.25 in/rev. Assuming the heat transfer factor was 0.80 and the melting factor was
\r\n0.65, determine (a) the relative velocity between the workpiece and the welding head, (b) the rate of
\r\nheat generated at the welding source, and (c) how long it took to complete the welding portion of
\r\nthis operation.
\r\n