Which of these joints cannot be disassembled for maintenance?

Welding creates a permanent joint between materials by fusing them together, usually through the application of heat. This process amalgamates the base materials into a solid structure that typically cannot be disassembled without damaging or destroying the joint. Once welded, the materials cannot be separated easily; any attempt to do so generally results in the destruction of the components being joined.

In contrast, threaded fastenings, snap joints, and bolts are all designed for disassembly. Threaded fastenings can be removed by unscrewing, while bolts can be taken out if unfastened. Snap joints are designed to interlock in a way that allows them to be easily taken apart and put back together without damage to the materials involved. This property of disassembly for maintenance is crucial in many engineering applications, where repair, inspection, or component replacement may be necessary.