Tutorial: Engineering technology Topic: Volume forming – hammer forging Prepared by: Ing. Elena Nová Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/ je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.
Volume forming – hammer forging
Anvil’s top swage is smooth and hardened
Free (smith) forging is divided on: 1. Hand 2. Machine Hand forging uses hand forging tools on anvil. For smith / hammer forging is used different machines, namely power hammer and presses.
Steel hearth – fuel is black coal or coke Smith’s hammers
Hammers are made from steels with Carbon content – C 0,7 to 1%. Both sides of hammer are hardened. Recessed/stepped hammers have hardened only surface.
Type of smith hammers – recessed hammers SharpSet (flat) hammer Profiled hammerFore (Sledge) hammer
Black smith tongs – are adapted to the shape of holding material. Tongs main parts: Jaws Lock Handle Smith tongs “Wolf jaws“
Forging temperatures in Fe – Fe 3 C diagram
Basic forging operation at hand forging: 1. Extension 2. Smoothing / planishing 3. Shouldering 4. Ramming 5. Bending 6. Punching 7. Black smith welding
1.Extension (Length forging, drawing). It is the most used operation. 2. Planishing is provided by material hammering onto set hammer.
3. Shouldering is rod thinning in given length Shouldering is done on rod’s one or both sides.
4. Ramming – strengthening of semi-product.
Forged welding – is the oldest type of welding. Forged welding is done at temperature of 1300 deg. C (white heat / incandescence). Welding is called ‘butt weld’ (short rods of dia. 15mm) or overlapping.
How is ‘smith forging’ divided? Name forging tools. Name hammer types? Name basic black smith works. What temperature is used at forged welding? What is used at machine forging?
Explain forge extension. Explain smoothing. Explain shouldering. Explain ramming. Explain bending. Explain cutting. Explain punching.
kripta_tkp/sekce/03.htm kripta_tkp/sekce/03.htm Strojírenská technologie, Otakar Bothe,1980