# Gearbox design | Mechanical Engineering homework help

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Explanation of the work:

1. Each student will be given an assembly drawing. 2. Be aware that bearings and other purchased parts come with standard

dimensions (use a ruler and round to a standard dimension) 3. Do all the QC ensuring clearance in all bearings (if liner dimensions are

very small, you can put the QC elements is a table with appropriate explanation of the element)

4. Do all QCs ensuring clearance in gear engagement (usually radial QCs) 5. Create part drawings of all gears and shafts and dimension them

appropriately (use ruler to measure the nominal) it is important which exactly dimensions will be used.

6. Pick appropriate method and calculate the tolerances for the QCs for the clearance in the bearings (use the following tolerance +0.05, +0.15). Use nominal measured by a ruler and rounded to standard dimensions for standard parts.

7. Pick appropriate method and assign tolerances for all elements for the QCs ensuring clearance in the gear engagements (use the following tolerance + 0.03, + 0.1)

8. Produce part drawings of the gears and shafts and show where appear the calculated from the QC tolerances.

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9. ASSIGNMENT: Sustainability analysis of a design and sustainable manufacturing routes for critical parts

A customer has offered to your company to undertake the work for producing a device or

equipment designed by a design bureau. Your company assigned 3-4 people to analyse the

design work and to work out suggestions for sustainable manufacturing of critical parts from

the design. Your analysis will be used to assess the complexity of the design, to assess the

load of the manufacturing equipment and possible bottle neck operations and finally will

allow the top management of the company to offer a quotation to the customer stating how

much will the work cost and when the production will be ready. Your work also will provide

customer with suggestions and ideas of design improvement, manufacturing constrains and

guarantees for the functionality of the designed equipment.

Prepare a formal written report: The assignment is to develop the technical part of a business case to support the design and

manufacture of a specific device or equipment. Prepare a Word document and write

formally (i.e. avoid use of “I” or casual terms). Start each of the four parts on a new page

(this is to aid the marking process).

Part 1) Introduction 25% Evaluate the suggested for analysis design. What is it, which are the most common types of

such devices or equipment? What are the critical functioning parameters, what is the devise

or equipment used for, etc?

Part 2) Design Quality Chains for the critical functional parameters of the suggested design 25%

1. Create the Quality chains required for the specific assembly which will guarantee the

workability of the design; Short Quality chains can be graphically represented on the

assembly drawing, but the long Quality chains, where the graphical representation

will be difficult, should be described as shown below:

Example:

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AΣ – clearance in the gear engagement of …

A1 – radius of the basic diameter of …

A2 – run-out of …

…….

2. Select a method of ensuring the quality of the functional parameters and calculate

the Quality chains using methods of full interchangeability, partial interchangeability,

group interchangeability and compensation method. If needed justify the use of the

method of compensation and calculate the compensator(s). The aim is to assign the

biggest possible tolerances and guaranteeing the workability of the design. This is

directly linked to the sustainability of the new product!

Part 3) Detailed design and tolerancing 25%

1. Sketch the selected (or pointed by the supervisor) parts and dimension them;

2. Assign tolerances of all dimensions of the selected parts and justify the selection. If

3. According to assigned dimensional tolerances and findings from the Quality chain

calculations, assign tolerances of shape and position if and where needed.

Part 4) Manufacturing routes for critical parts 25%

1. Using sketches show the sequence of achieving dimensions on the critical parts. The

dimensions given in part 3 must be achieved in part 4

2. Use the right symbols for clamping and removing degrees of freedom

3. Make sure stack up tolerances is avoided as much as possible