且在长期运行中情况比较稳定，采用该型式叶轮的泵轴向力较小，且可以在前后盖板上设置副叶片。

And the situation in the long-term stable operation, use the type of impeller shaft to the edge of the smaller, and can be set up before and after the Vice-leaf cover.

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在不同的条件下，通过选择合理的前后盖板材料、长度、直径、锥度，可使换能器的频带宽度得到优化。

With the different conditions, reasonably selecting the material, length, diameter and taper of ahead or back blind flange can realize the broadband optimization.

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但如果条件许可，仍建议开关柜后盖板到墙之间以及开关柜两侧到墙之间均留出适当的通道以便安装维修。

But if conditions permit, we still suggest that to leave appropriate channels on both back and side for installation and maintenance.

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