Sheet-Metal Copper Nuts & Slotted Locking Copper Nuts

Sheet-metal copper nuts and slotted locking copper nuts are two widely used varieties of copper fasteners. But why are copper nuts specified in everyday production? Copper nuts offer key advantages: they do not rust easily, resist corrosion, and provide superior heat and electrical conductivity. They are therefore the natural choice for anti-rust, high-temperature, conductive and heat-transfer environments such as faucets, valves and electrical switches.

The other major use of copper nuts is in injection molding — they are heated and then embedded into a plastic part, or molded directly into the component. As noted above, brass has good thermal conductivity: embedding a pre-heated copper nut speeds up the work, and the heated nut quickly transfers heat to the plastic, softening the area around the hole so the nut can be pressed in. What happens with direct mold injection? PA, NYLON and PET all have melting points above 200°C. Once the copper nut is heat-staked into the plastic its temperature rises sharply; after injection the plastic cools, crystallizes and hardens rapidly. If the copper nut is still at high temperature at that moment, the result is predictable — the interface between the nut and the plastic loosens or develops cracks. That is precisely why a copper (not steel) nut is used in injection-molded assemblies.