drop forged/pressed steel ?

Forging means that you take a lump of red hot steel and pound it under a shaped hammer (called a "die") until it is the right shape. A pressed steel coupler will be made from pieces of steel sheet which are formed in a press at room temperature and then (probably) welded together. I would guess that the forged couplers will be stronger. Forgings are usually very strong because of the alignment of the grains in the metal.

Chris

So what does the "drop" mean?

Peter

According to :

The upper part of the die, a "striker" is quite massive, and is raised under power, and then released, letting gravity do the job. This has the advantage that if something is thicker than expected, and can't be crushed all the way, you don't wind up breaking gearing inside the system -- the striker just *stops*.

You could even raise it with a hand-cranked system, and release it by pulling out a pin or something similar. It would just be a lot slower that way, so you would have to put the workpiece back on to heat every time you start cranking the striker to its "cocked" position.

Enjoy, DoN.

Hmmm. Dad rigged something like that once. However, it sucked for its intended use. He rigged up a trip to drop one of our levee rollers from the winch truck with the idea of flattening some old cars for the junkman. The trip just had a notch to hold the chain around the spool, and a 3' handle welded to it with a long rope. He winched up the roller, backed it over our old Travelall, and then dropped the roller (concrete spool about 2 tons). The car wrapped around that thing like a coke can stuck on your heel. It took quite a while to cut it loose.

Pete Keillor

"Christopher Tidy" .(clip) I would guess that the forged couplers will be stronger. Forgings are usually very strong because of the alignment of the grains in the metal. ^^^^^^^^^^^^^^^^^ Another reason forgings are generally stronger is that the dies can be shaped so that the metal varies in thickness as needed for strength. Reinforcing webs and radii can be designed in, to reduce stress, increase stiffness and improve fatigue life. In a stamping, the dies can stretch the material, making it thinner, but they can't make it thick and strong next to a hub, for example.

Remember Junkyard Wars? There was an episode on curshing a car to a particular height and one of the teams built a drop hammeer setup for doing this and they won. The other team build a press and it broke several times.

-- Why do penguins walk so far to get to their nesting grounds?