The reason is a unique bronze gate wedge that's shaped like a block instead of round like all other gates.

原因在于这种独特的青铜闸阀楔板形状上如同方形阻断闸门，而不象其它类型的闸阀。

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Meanwhile, the wedge-shaped design of the fixture block can play the role of self-locking, and thus causing the moving and static contacts to be steadily contacted.

同时，卡块的楔形设计能起到自锁的作用，使动静触头能够稳定接触。

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The bottom of the disc is made of knife-shaped gate with a cut off function of the medium. When gate is closed, oblique plane of gate valve encounters wedge block of gate to achieve sealing effect.

闸板底部做成刀形斜面具有切断介质功能，而且闸板关闭时通过阀体上的锲块紧靠闸板斜切面使得闸板紧紧贴靠阀座密封面，从而起到了密封效果。

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