12. What is forging? 13. One way to classify forging operationsis by the degree to which the work is constrained in the die. Bythis classification, name the three basic types. 14. Why is flashdesirable in impression die forging? 15. What is a trimmingoperation in the context of impression die forging? 16. What arethe two basic types of forging equipment? 17. What is isothermalforging? 18. What is extrusion? 19. Distinguish between direct andindirect extrusion. 20. Name some products that are produced byextrusion 21. Why is friction a factor in determining the ram forcedirect extrusion but not a factor in indirect extrusion 22. Whatdoes the centerburst defect in extrusion have in common with theroll piercing process? 23. What is wire drawing and bar drawing?24. Although the workpiece in a wire drawing operation is obviouslysubjected to tensile stresses, how do compressive stresses alsoplay a role in the process? 25. In a wire drawing operation, whymust the draw stress never exceed the yield strength of themetal?
