Mild Steel Case Study
Functional Development to Cost (An Incline)
Function Creative Ideas & Development Estimated Cost (Rs)
Provide Surface 1) Change the material to Mild Steel 40 2) Change the copper to brass 70 3) Combine function of bracket 85
(For sliding surfaces, copper facilitates lu-brication & high con-ductivity.) (A) The existing cost of the Incline + Bracket assembly = 112 (B) Reduction in Cu + increase in M.S. contributes to the cost = 40 (A - B) Total saving = 72 …show more content…
Convert all parts into M.S. a) Reduced Inventory, 1 a) Surface treatment required 2 2 b) Reduced Tooling 3 b) Corrosion problem 1 c) Ease of Assembly 2 c) M.S. is a bad conductor 3 d) Simpler Design 2 d) New material procurement 1 e) Material cost lesser by 90% 2 e) New Design 1 f) Reduced corrosion 1 f) Alter tooling 1 Total 11 9
2. Convert copper into brass a) Better sliding surface 1 a) Fresh procurement 1
-2 b) No corrosion problem 1 b) New tooling required 2 c) No surface treatment. 2 c) Brass vol. up by 60% than Cu. 3 d) Material cost lesser by 33% 1 d) Change in Design 1 Total 5 7
Reduced copper thickness a) Ease of Assembly 2 a) Alter material procurement 1 7 b) Simpler tooling 3 b) New tooling …show more content…
should not be used here for its poor con-duction of current ranging 200 – 400 amps.
The design required brass mass is more than that of copper for this same function.
The reduced c/s area is sufficient to withstand max. possible leaked current of 400 amps.
Length of “The Incline” is for keeping the Scraping Earth (M) in contact for all the possi-ble positions of the Breaker inside the Cradle during its working life. Accordingly, the length and width is optimized for the incline.
Figure 3: Net Weighing for Ideas 1to 4
6. DEVELOPMENT AND IMPLEMENTATION PHASE
6.1 Activity matrix: New design (Fig: 4), as combination of Ideas 3 & 4 was taken for the tests.
S. No. Activity Steps Taken Results Conclusion
1. Prototype samples In-house Samples Trials successful
Satisfactory functional perfor-mance. Samples Procured Trials with no defect. Tooled up samples need to be procured & validated.
2. Tool design & Manufac-turing Existing Tool Modi-fied for MS The first lot of MS & Tool is ok. Larger lot need to be tried for design validation & implementa-tion. Jig for hole in In-cline Oval counter-sunk holes on Incline Proper Counter-sunk drill is to be used with higher relief