Design & fabrication of lapping machinefor fatigue test sample A Project Seminar on Design & fabrication of lapping machinefor fatigue test sample

Project team Amrit Kumar (1JS08ME008) Nilesh Meher (1JS08ME033) Chethan P (1JS07ME001) Under the Guidance of: Prof. Sankarlingegoud N

introduction Lapping is a process in which two surfaces are rubbed together with an abrasive between them. This can take two forms. The first type  (grinding), involves rubbing a brittle surface against another brittle surface with an abrasive in between them. This produces microscopic conchoidal fractures as the abrasive rolls about between the two surfaces and removes material from both.

introduction The other form involves a softer material  for the lap, which is "charged" with abrasive. The lap is then used to cut a harder material—the work piece. The abrasive embeds within the softer material which holds it and permits it to score across and cut the harder material Taken to a finer limit, this will produce a polished surface We are using this form of lapping

Problem definition Component gives wrong interpretation on fatigue test because of surface having irregularities such as tool mark or rough finish So lapping is accomplished to give a smoother finish in order of 30UM. Lapping Machine available in the market cost around 1.64Lac to 4.5Lac which is costly for lab dealing with fatigue test

Design of individual part Female Block Material Used = Mild Steel (EN8)

Male Block Material Used = Mild Steel (EN8)

Cam Plate Material Used = Mild Steel (EN8) Hole is drilled for lift

Fixture Material Used = Mild Steel (EN8) Made from 6mm sheet metal plate

CALCULATION

Machine

Components and specification Machine Stand Length = Width = Height = Material = Stainless Steel Fixture Thickness = 6mm Material = Mild steel EN 8

Gear Box 3Litre Wet Grinder Motor Single Phase motor Power = 1HP Volt = 200/220V Speed = 1440rpm Gear Box 3Litre Wet Grinder

Pulley Diameter = 14inch Material = Zirconia Steel Drill Chuck 5mm-20mm Comes with 4MT Arbor with chuck key

Pulley Diameter = 7inch Material = Zirconia Steel Pulley Diameter = 4 inch Double Pulley Material = Zirconia Steel

Bearing Connected to shaft Bearing with housing Inner dia = 20 mm Outer dia = 40 mm Housing dia = 50 mm Bearing Connected to shaft

A32 A64 Belt Material = polyester cord Neoprene Jacketed Cross section shape = trapezoidal Shape = V Shape Optimal speed range is 1000–7000 ft/min

Rectifier Used in 2motor DC Motor 3000rpm 12 volt

Transformer 24 volt output Bush Material = Silicon Carbide Size = 50mm dia

Sanding Belt Grade 60, 120,240 available 60 grade used ½ inch belt

TECHNICAL SPECIFICATIONS Sl. no Feature Description 1 Total weight 40 kg 2 Maximum height 600 mm 3 Maximum width 500 mm 4 Maximum length 1500 mm 5 Working speed 15 rpm 6 Capacity 18 kg/hr 7 Geneva wheel Diameter = 120 mm Thickness = 6 mm 8 Geneva driver Diameter = 140 mm 9 Electric Gear Motor 0.5 hp, 3 Phase,15 rpm 10 Shaft Length= 900 mm Diameter = 20 mm

COSTING DETAILS Input Materials(Direct Costs) SL. NO PART QUANTITY PRICE IN RUPEES 1 Motor 6500 2 Big Sprocket 6 1200 3 Small Sprocket 240 4 Plummer Block 8 720 5 Shaft 500 Chain 700 7 Geneva 900 Total 10,760

Assembly Costs (Indirect Costs) Sl . NO. FABRICATION PRICE IN RUPEES 1 Cups 400 2 Cutting, Drilling, Slot Cutting etc 200 3 Over Costs 500 4 Total 1100 TOTAL 11860

CONCLUSION Simple in design Economical Less space requirements

SCOPE FOR FUTURE WORK Speed can be decreased by using 3 phase motor

Bibliography BOOKS WEBSITES R S Khurmi and J K Gupta, A Text of Machine Design, Eurasia Publishing House (P) Ltd, 13th Edition, 2000 Dr. K Lingaiah, Machine Design Data Handbook, Suma Publishers, 4th Edition, 2006 WEBSITES www.google.com www.wikipedia.com www.sciencedirect.com www.thehindu.com

THANK YOU