A paper machine processes rolls of paper having a density of 984 kg/m3. The paper roll is 1.50-m outside dia (OD) X 0.22-m inside dia (ID) X 3.23 m long and is on a simply supported, hollow, steel shaft with Sut = 400 MPa. Design a 2.5:1 reduction spur gearset to drive this roll shaft to obtain a minimum dynamic safety factor of 2 for a 10-year life if the shaft OD is 22 cm and the roll turns at 50 rpm with 1.2 hp absorbed.

Different types of steels contain different elements that alter the characteristics of the steel. for each of the following elements, explain what the element does when alloyed with steel.

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.

The higher the astm grain size number, the finer the gran is. a)-true b)-false