This is in addition to what Anil Kumar Arora has said. You should have mentioned your designation and the purpose of this query. Is your company into the production of welding electrodes, etc.?
Costing is the job of your ICWA. When deciding the product cost, the following factors are considered:
a) Fixed Cost: It includes interest on capital, interest on fixed assets, rental of the premises, etc.
b) Variable Cost: It includes setup cost, labor charges, operational expenses, maintenance charges, scrap generated, etc.
c) The third factor is inventory carrying charges. This is for raw material or inventory of finished goods.
d) Lastly, your admin overhead.
In-depth analysis of the costing is done when companies make the "Make Vs Buy" decision. For higher volume, it makes sense to do production in-house. However, for lower volume, it is better to outsource the production. Now, how much is higher and how much is lower, that decision can be made only with an example. The decision will vary from one industry to another, one company to another, and lastly, one product to another.
Ok...
Dinesh V Divekar