Weld On Hinges
Known by many names including bullet hinges, barrel hinges and lift-off hinges, weld on hinges are small hinges that connect two separate metal parts, typically doors and door frames, while still allowing for up to 180 degrees of swinging movement. Weld on hinges offer high control quality and are typically used in heavy duty industrial applications such as steel cabinets, electrical boxes, steel gates, machinery doors, transformer enclosures and tool boxes. Not only used in industrial applications, weldon hinges are also used in industries such as marine, automotive, shipping, construction, electronics, commercial and more for applications such as barbecue pits, fishing equipment, tool boxes, cab enclosures, security gates, traffic light controls, truck or trailer bodies, boats and cabs. Typical materials used in weld on hinges include iron, stainless steel, zinc-plated iron, low carbon steel, brass, steel and aluminum alloys. Able to withstand substantial loads as well as being suitable for narrow frames, heavy duty weld on hinges are excellent alternatives to more traditional hinges such as butt hinges and piano hinges.
Weld on hinges are designed as two halves of a hinge that can separately be directly welded on to the surfaces. These halves are referred to as the male and female barrels, which is why weld on hinges are also referred to as weld on barrel hinges or just barrel hinges. The male barrel is the barrel with the pin and the female barrel is the barrel without a pin. The male barrel is welded onto the structural surface, such as a door frame, while the female barrel is welded onto the other surface, such as a door. Since doors that use weld on hinges become lift-off doors, the female barrel must fit on top of the male barrel. This is because lift-off doors are often dropped and the bottom barrel must have the greater load bearing capabilities of the two. The advantage of lift-off doors is that they can be lifted off of the hinges at anytime, without the hassle of having to unscrew the hinges. The materials used to make weld on hinges first undergo the extrusion process, in which round metal stock called "billets" or "logs" are pressed by a ram through a die, which is a hollow profile that shapes the metal into a specific extruded shape as the billet is squeezed through. The materials are then drilled and cut to the required hinge shape.