Question 3. Three tool materials are to be compared for the same finish turning operation on a batch of 100 steel parts: high speed steel, cemented carbide, and ceramic. For the high speed steel tool, the 170 Taylor equation parameters are: n = 0.125 and C = 70. The price of the HSS tool is $15.00 and it is estimated that it can be ground and reground 15 times at a cost of $1.50. Tool change time = 3 min. Both carbide and ceramic tools are in insert form and can be held in the same mechanical toolholder. The Taylor equation parameters for the cemented carbide are: n = 0.25 and C = 500; and for the ceramic: n = 0.6 and C = 3,000. The cost per insert for the carbide = $6.00 and for the ceramic = $8.00. Number of cutting edges per insert in both cases = 6. Tool change time = 1.0 min for both tools. Time to change parts = 2.0 min. Feed = 0.25 mm/rev, and depth = 3.0 mm. The cost of machine time = $30/hr. The part dimensions are: diameter = 56.0 mm and length = 290 mm. Setup time for the batch is 2.0 hr. For the three tooling cases, compare: (a) cutting speeds for minimum cost, (b) tool lives, (c) cycle time, (d) cost per production unit, (e) total time to complete the batch and production rate. (f) What is the proportion of time spent actually cutting metal for each tooling?

In a turning operation, cutting speed =200 m/min; feed = 0.25mm mm/rev, and depth of cut = 4.00mm Thermal diffusivity of the work material = 20m mm^2/s and volumetric specific heat =3.5(10^ -3 )J/mm^ 3 -C If the temperature increase above ambient temperature (20degreesC) is the angle measured by a tool-chip thermocouple to be 700degreesC, determine the specific energy for the work material in this operation.

A student is performing a turning operation with a workpiece with an initial diameter of 40 mm to produce a 30 mm diameter rod that is 100 mm long. The lathe power is 20 kW and is operating on 85% mechanical efficiency. If the student set the cutting speed to 0.5 m/min and the cutting tool is set to have a rake angle of 5 degrees:  a.) What material can we choose for the rod is the coefficient of friction is 0.5? b.) If we select 4130 normalized heat-treated steel for the rod, and coefficient of friction is 0.5, what will the maximum depth of cut we can achieve?