All wrecking bars produced at Svedbro Smide are hand-forged, and the wrecking bar is thus as good as its blacksmith. The undistorted forged wrecking bar is a guarantee of the blacksmith’s professional skills and the quality of the wrecking bar. All chords have been removed and our blacksmiths can thus spend more time forging a good wrecking bar, which results in no unnecessary post-work being needed. Post-work work that is otherwise usually done to hide shortcomings in the forging itself. At Svedbro Smide, the forging craft takes its time.
Forging and rough grinding
A special alloy spring steel is heated to about 1200C. The steel then has a reddish-yellow color. The blacksmith quickly and skillfully handles the hot, glowing steel and presses it out into octagonal bars. When the rods are ready, the steel is heated once more so that the blacksmith can forge the claw extractor and the chisel part, and the steel is then hung up for cooling. When the steel has cooled, the claw extractor and the chisel part are roughly grinded and then heated once more so that the blacksmith can bend out the rounded heel.
The forging press that is used, strikes at about 80 blows per minute, where each blow has a pressing force of about 180 tons. The blacksmith finishes by stamping the Svedbro Smide’s sign under the claw off the wrecking bar. The sign conveys a message that the wrecking bar is well made and thus approved. After approval, the wrecking bars are hung up for cooling.
Hardening, Tumbling and Grinding
After forging, the entire wrecking bar is cured by heating it to approx. 860 ° C and then rapidly cooled in cold water. The hardening makes the steel harder. It is important that the entire wrecking bar is hardened as it, among other things, strengthens the resilient property. A resilient characteristic in the wrecking bar provides better strength. In addition to cooling in water, oil or lead can also be used as a coolant. But at Svedbro Smide we only use water, as it is the most environmentally friendly alternative.
When the wrecking bar has cooled down, a quality check is also carried out to see that there has been no cracking in the steel, and that the forging and hardening has been done correctly.
After hardening, the wrecking bar is tumbled, which removes forging slag that may have formed on the surface during forging. This also makes the surface more resistant to rust. After tumbling, the hardness of the steel is checked so it’s not too hard or too soft.
The last thing that happens is that the wrecking bars claw extractor and chisel part are grinded and polished. It is of great importance that the chisel parts and the claw extract are correctly ground. Both ends of the must be thinly ground and have a wide, polished contact surfaces to get under boards but at the same time minimize damage to the surface that is used as breaking support. The nail extractor must have a distinct V-shape with angles that will give a high ability to pull out nails of varying size and head shape. Finally, the wrecking bar is painted blue, yellow, lime, orange, pink, white or black.
All our wrecking bars are quality checked before they leave the factory so that we can be absolutely sure that there are no faults. All Svedbro Smide’s wrecking bar have a guarantee of 20 years.