How to calculate forging weight
How to calculate forging weight
(OP)
I am a gear manufacturer and have newly entered the field. Can someone please tell me the methods to calculate the forging weight which my suppliers calculate or if there is any software available for that. The materials I use are either 20MnCr5 or EN 8.
Any help would be greatly appreciated as calculating costs for my products is getting difficult when I am abroad and not able to get costings from my suppliers.
Thanks
Ankur
Any help would be greatly appreciated as calculating costs for my products is getting difficult when I am abroad and not able to get costings from my suppliers.
Thanks
Ankur





RE: How to calculate forging weight
RE: How to calculate forging weight
Is there a software I can use where I input the final drawing or dimensions and get the forging weight (net and gross)..
Thanks
Ankur
RE: How to calculate forging weight
RE: How to calculate forging weight
When pricing the raw material for a forging, you must include the excess material that is usually trimmed from the finished forging. The flash in a die forging, or the prolong in a roll forging.
Gear forgings are normally produced from wrought bar stock. High performance gears are usually produced from vacuum melt wrought bar stock, which can be quite expensive. So minimizing machine stock in the forging can be important.
Good luck to you.
Terry
RE: How to calculate forging weight
Don't know if your question was answered. But I'd add that using a forging for many gear applications can be quite cost effective. Even with modest production quantities, the cost of forging dies for a simple spur gear blank will pay-off. This is due to reduced scrap material produced and the high raw material cost of premium gear steels.
RE: How to calculate forging weight
Thanks for your replies. Can someone please tell me how to add tolerances for forging stock for draft, radii/fillets, surface flatness, decarburization, etc. I mean what percentage of the net weight should i add for these processes?
I calculate volume and then multiply with the density of 20MnCr5 which is 7.81 g/cm3 to get the mass.
Thanks
Ankur
RE: How to calculate forging weight
Stock for draft can be calculated assuming a 4-5deg increase from the min net surface. Stock for removal of decarburized or metallurgically unsound surfaces is typically around 1/8 inch, but once you refine your forging and HT processes you can probably reduce this stock allowance to about half this thickness. Steel die forgings usually require fairly generous fillet and corner radii. If the transitions in the forging sections are too abrupt, it will result in reduced life of the forging dies, and/or forgings with cold laps, seams, etc.