求翻译：在UCS1、GCS及UKMS为了保证计量的准确性，流量计前后的阀门所需阀门拟选用能保证双向零泄漏的强制密封阀门，阀芯和阀座之间无摩擦。要求阀门扭矩小，开启自如，阀门易损件便于维修和更换，其使用寿命包括内外零泄漏的性能应在20年以上。需要自动切换流程的阀门配备电动执行机构。是什么意思？

In UCS1, GCS and UKMS to ensure measurement accuracy, the flow meter selection valve required valve before and after the proposed guaranteed bi-directional zero-leak forces sealed valve, without friction between the valve and valve seat. Require small valve torque can be opened freely, wearing parts

In UCS1, GCS and UKMS to ensure measurement accuracy, the flow meter selection valve required valve before and after the proposed guaranteed bi-directional zero-leak forces sealed valve, without friction between the valve and valve seat. Require small valve torque can be opened freely, wearing parts