1. As Engineering Manager on a Manufacturing Line Responsible for Building a Cable Assembly

ISE 370 Tolerances AssignmentFall_2017

Due: Thursday Oct. 12th

1. As engineering manager on a manufacturing line responsible for building a cable assembly, you are

charged with the responsibility of producing a cable whose voltage drop should be 110 +/- 10 mV.

A cost of $36 is associated with reworking parts to make a change of 3 mV in the process.

Determine the quality loss function & evaluate the specifications based on economic considerations.

Specifications at which the process should be economically be set are found by:

2. What is the cost savings per unit for decreasing the variability to the new specifications in

problem #1.

3. If the force exerted by a brush spring in an electric motor is too low (5 g/cm2), armature contact will be lost and the motor will fail to operate. If the force is too high (15 g/cm2), the brush will wear out prematurely and cause motor failure. The ideal force is 10 g/cm2. The cost of a motor failure is the repair cost of $50.

(a) Compute the k value for this loss.

(b) Compute the expected loss for a production run of springs with an average force of 9.0 g/cm2 & a

standard deviation of 2.0 g/cm2.

Hint:Expected Loss = k [(average of sample – nominal mean)2 + s2]

4. If the blackness (measures by ISO optical density) of the image from an electrostatic copy machine

drops to 1.0, a service call is triggered at a cost of $50. The customer expects the density to be 1.5,

which is the maximum attainable. Construct the loss function for this situation.

5. If the population of copier machines is able to hold an average density of 1.2 with a SD of 0.1,

compute the expected loss using the loss function found in problem #4.

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