For this reason, the well designer generally seeks to maximize the fluid velocity (or other measure of jet energy) to achieve maximum cleaning at the bottom of the hole.
Once the impurities in the water or the cleaning solution sink into the holes of the hole plate, the majority can sink at the bottom and stop in order to avoid the secondary pollution.
水或洗涤液中的杂质一旦沉入孔板的孔中，其大部分就会沉入底部并且静止在那里，避免了二次污染。
3
Cleanout hole series can be set at the cornet from the bottom tank shell course to the bottom of the heavy oil storage tank for cleaning and draining during maintenance.