Ultra-deep Wells or geothermal Wells often face formation temperatures of more than 220 ° C in drilling construction, and deep Wells often drill salt paste layer, so the company has developed ultra-high temperature water-based drilling fluid system with temperature resistance of more than 220 ° C. The ultra-high temperature system is improved on the basis of the classic high temperature resistant drilling fluid system, and combined with the new high temperature resistant polymer, the high temperature resistance of the system is further improved. The drilling fluid has the advantages of traditional polymer drilling fluid, and its resistance to high temperature and rheology are further optimized, making it more suitable for the use of ultra-deep Wells in complex situations.

The fresh water ultra-high temperature system mainly consists of sulfonated materials, new polymers and nano-sealing agents, and treatment agents cooperate with each other, so as to realize the control of rheological properties and filtration loss performance. The main materials include: Sulfomethyl phenolic resin - SMP, sulfonated lignite - SMC, sulfonated Lignite phenolic resin - SPNH and sulfonated asphalt -FF-1, new polymer PSP. In addition, by adding new nanomaterials, the sealing performance and rheological properties of the system are further improved.

The system is suitable for a wide temperature range, according to the actual temperature at the bottom of the hole, from 220℃ to 260℃, providing a better optimization scheme, in addition, the system also has a better pollution performance.

The ultra-high temperature system provides:

- Good compatibility

- A wide range of applicable densities improves the problem of barite settling

- Good thermal stability under high temperature and pressure conditions

- Strong anti-pollution ability

- Drilling fluid rheology can be controlled

High temperature and high pressure filtration loss is small, mud cake is thin