Balancing Bolts and Welding Techniques
Wear plates can be applied using methods such as bolts, welding, or a combination of both.
Wear liners are typically installed using countersunk bolts, which create smooth surfaces on the inner face of the skirtboard and allow for easy replacement of the liner. Alternatively, liners can be welded into place, although this method poses challenges when it comes to replacing worn liners. When welding is necessary, it's crucial to use appropriate welding materials and techniques that match the liner material.
Another installation technique involves plug welding the wear liner from outside the transfer point. This process starts with drilling or cutting holes through the plated steel wall, followed by welding the back of the liner to the chute wall. This method ensures installation without bolt heads or holes protruding into the loading zone, which could otherwise become targets for material abrasion. The liner maintains its full thickness for extended wear-life. When it's time to replace the liner, the process involves cutting out the plug welds and installing new liners using the same holes.
During welding installations, careful attention must be paid to controlling the stress introduced into the lining metal. Improper installation can lead to residual stress, similar to how bubbles form in wallpaper when the edges are secured first. While abrasion-resistant plates do not bubble, they can develop stress if installed incorrectly, especially when the structure flexes during normal operation. Such stresses may cause cracks or breaks in the wear liner.
To avoid such issues, it's essential to adhere to proper welding techniques. One common practice is "backstep" or "back welding," where stitch welding is applied along the top of the plate, drawing each bead back towards the welded end. Additionally, workers need to select the right welding rod to ensure the strength and durability of the weld joint.
Finally, operators should assess the conveyor structure itself, ensuring that the chute wall and surrounding support structures can withstand the added weight of wear liners effectively. This consideration is crucial for maintaining the overall integrity and functionality of the conveyor system.