煤矿在疏水降压防治水害工作中 ,常因水压过大 ,经常发生顶钻事故 ,造成突水 .本文主要介绍打疏放水钻孔时固定套管所用的止水器 (TheWater_stoppingdevice)的基本结构、工作原理、使用技术及使用效果 .通过这一设备的使用 ,较好地解决了顶钻难题 ,为煤矿的安全生产奠定了基础 . Coal mine drainage in the prevention and control of water damage in the work, often due to excessive pressure, top-hole accidents often occur, resulting in water inrush.This paper mainly introduces the basic structure of the stopwatch (TheWater_stoppingdevice) , Working principle, using technology and effect of use.Through the use of this equipment, it has solved the top drilling problem well and laid the foundation for the safe production of the coal mine.