The choice of coupling material mainly depends on the application scenario and performance requirements. The most commonly used is 45# steel, followed by higher strength 40Cr and stainless steel. The specific classification is as follows:
Main materials and application scenarios
◆ Carbon structural steel
45# steel: The most widely used, with good mechanical properties and cost-effectiveness, commonly used in general scenarios such as plum blossom couplings and star couplings.
40Cr/40CrMo: By adding chromium elements to improve hardenability and strength, it is suitable for diaphragm couplings and expansion sleeve couplings with large outer diameters or high loads.
◆ Stainless steel
It is corrosion-resistant and used in special environments such as chemical and food processing. For example, single diaphragm couplings are made of all stainless steel.
◆ Aluminum alloy
Lightweight and corrosion-resistant, commonly used in diaphragm couplings (such as long-span diaphragm couplings) and elastic couplings, some of which use aviation aluminum alloys to improve performance.
◆ Cast Iron/Cast Steel
Cast iron is wear-resistant but has low strength, while cast steel can be welded and has slightly higher strength. Both are low in cost and are mostly used in non-high-precision scenarios such as flange couplings and clamp couplings.
◆ Engineering Plastics
Such as nylon elastic couplings, which have electrical insulation and buffering properties, are suitable for occasions that need to absorb vibration.
Key factors for material selection
◆ Mechanical properties: 40Cr or aviation aluminum alloy is preferred for high torque scenarios;
◆ Environmental adaptability: Stainless steel is required for corrosive environments, and engineering plastics can be selected for humid environments;
◆ Economical: Cast iron or 45# steel can be selected in ordinary scenarios to reduce costs.
