In drilling fluid, cementing fluid, and fracturing fluid, the usage of CMC can help them reduce the water loss and improve their viscosity and with other advantages, which in turn can protect the wall, drill cuttings, protect the drill, avoid mud loss, and improve the drilling speed. CMC can be added to the mud directly or in the form of the liquid cement. Add 0.1–0.3% CMC to the fresh water mud and 0.5–0.8% to the saline water mud.