 Hello friends, I am Mr. P. P. Mitra Guthri, Associate Professor in Department of Mechanical Engineering at Valshchand Institute of Technology, Solaapur. Today we are going to discuss design of a progressive dye for given component. Now this design of a progressive dye for given component is to be discussed in two sessions. In today's session, we will discuss design procedure for progressive dye up to strip layout. Learning outcome for this session will be, students will be able to design a proper dye set for a given component. Now to study design procedure, first of all we have to define a problem and now this is the component shown in the sketch which is having square blank having 80 by 80 mm size with two holes pierced in it of 5 8 mm diameter having central distance between them is equal to 40 mm and rest of the dimensions are shown in the sketch. Now for manufacture of this particular component, it is necessary to design a dye set which is economical. Now material for this particular component is MS sheet, thickness of the sheet given is 1.2 mm, shear strength of that particular sheet given is 840 N per mm square, total quantity required per month is to per year is 10 lakh, production rate stipulated per day is 10,000 per day. Width of the stock available at our end is 80 mm, 82 mm, 84 mm, 86 mm and 88 mm and presses which are having spare capacity with us are 25 ton press, 30 ton press, 35 ton press and 40 ton press and we have to select the press out of this. Now before beginning the design procedure, first stage is a product study. In product study various criteria are to be discussed, first is material, material of the sheet is mild steel, contour size of the product is small because it is 80 by 80 mm, contour shape is a square so it can be regarded as a very simple shape, thickness of the sheet is 1.2 mm that is less than 1.5 mm so it is regarded as a low thickness. Accuracy of the product is low because there are no tolerances specified on any of the dimensions of the component so accuracy of the production of the component can be regarded as low. Quantity required is 10,000 per day means it is low quantity as 20 it is less than 25,000 per day and as our component has both cutting operations, direction of fiber is not at all important. Now next stage in design is selection of stock. Now we are going for strip stock. Justification for that is our production rate is low as already stated our daily production is 10,000 pieces per day 10,000 parts per day as it is less than 25,000 parts per day we can say that our production is rate is low and secondly as our sheet thickness is less than 1.5 mm that is 1.2 mm our sheet thickness is low so we can very easily go for strip stock and along with strip stock we are going for single pass layout. Next is design selection of die set for selection of die set we have to consider what are the operations involved. If you look to the component geometry you will find that there are 2 holes of 8 mm diameter which are to be pierced and then we have to carry out blanking of 80 by 80 mm sheet. It means that both operations are cutting operations which makes the design of die set easy so we can go with solid and single piece drop through die set. Next is now before going for the next procedural point I will ask you one question which material you will select for actual die cavity and punch. Think for a while and try to find out the answer. Now selection of type of die set is one of the important thing. Now manufacturing of this component if you look to the component it can be accomplished with various dies. First of all two simple cutting dies can be used to manufacture of this particular component. One first simple cutting die cut blank of 80 by 80 mm then carry out piercing of 2 holes of 5 mm on that cut blank on another simple die that is possible or you can use compound die in which you can cut the blank and then carry out the piercing of hole at one stroke or you can go with progressive dies and you may also think of transfer dies that is this component manufacture is easily possible with all types of dies and that is why we have to select most economical and proper die set. Now no doubt we are going for progressive die set for the very simple reason that is compound dies are complex costly and difficult to maintain. Transfer dies are useless in this case as operations involved are only 2 and cost of single piece progressive die will be much less and it will be much easier to operate as compared to two simple single operation dies. So now next part is if we are going to select a progressive die we have to calculate a quantity or entity called as a scrap bridge. Now what is a scrap bridge? Now scrap bridge is very essential to decide width of the stock and to decide strip layout because strip layout is to be strip layout is most important step in design of a progressive die because strip layout will further decide percentage utilization and force required and all other things. So to select width of the stock it is necessary to calculate scrap bridge it is denoted by later a so it is given as a is equal to sheet thickness into 1.5. Now our sheet thickness is 1.2 mm so 1.2 mm into 1.5 is equal to 1.8 mm is equal to 2 mm so our scrap bridge is 2 mm. Now I have shown strip layout in the sketch. Now this sketch is not to the scale but if you observe our strip is travelling in the direction shown by the arrow our width of the strip is 84 mm we have selected strip stock of width 84 mm for the very simple reason that is we have left 2 mm on either side of the component as our component width is 80 mm and length is 80 mm so width of the stock optimum width of the stock has to be 84 mm and then in between the two components we have 82 mm distance which will decide pitch of the advancement now what is pitch of advancement let me tell. Now pitch of advancement means now when this is the layout first of all on the first on the right side right portion of my strip piercing operation will take place at the same time blanking operation will take place on the part adjacent to it. Now first part on which blanking operation takes place is a waste but now in the second operation strip will progress in a direction of travel as a result of which the strip which has two pierced holes will advance by distress equal to pitch that is 82 mm and will come under blanking die and punch. Now blanking operation will be carried out by that blanking and die and punch set and our blank with two pierced hole will fall down and strip will advance further and at the same time piercing operation will take place in a strip coming under the piercing die and punch set and in this way progressively the operation will continue and in this case this will be the blanking operation is automatically done there is no there is no requirement for positioning of strip stock it is automatically positioned and strip holder will hold the strip positively and every time after every operation strip holder will be lifted up and again when strip advances by distress equal to pitch it will fall down and it will hold the strip in position and further operation is carried out during every stroke it will happen and strip layout will help you to understand the design of progressive die and now in this session we will stop here and for further reading I will ask you to refer textbook of production engineering by PC Sharma tool designed by Donaldson and press tool designed by IGTR Aurangabad.