chain folding

例句：

1. 1. The chain folding mechanism is used to secure the luggage.
   链条折叠机制用于固定行李。
2. 2. The chain folding design makes it easy to store and carry.
   链条折叠设计使得存储和携带都变得容易。
3. 3. The chain folding system is widely used in industrial applications.
   链条折叠系统在工业应用中广泛使用。