For the cage, considerations include friction, strain, inertia forces, and in some cases, the chemical action of certain lubricants, solvents, coolants and refrigerants.

• 对于保持架,要考虑的因素包括摩擦力、应变力、惯性力,在某些情况下还要考虑同某些润滑剂、有机溶剂、冷却剂和制冷剂的化学反应。