High-temperature, large temperature difference system.

LT1 Well: Well depth 5961m, bottom temperature 164.5°C. The original design of cementing the 139.7mm tail pipe was changed to casing cementing, and the cement slurry was returned to the surface. The slurry column structure was designed as a four-body system with densities of 1.85+1.45+1.85+1.88g/cm³. The cement slurry was returned to the wellhead in a single operation, achieving an overall wellbore quality rate of 85.03%. This set new records for the Jidong Oilfield in terms of the maximum temperature difference (135°C) and the longest single-stage cementing section.

JYT1 Well: A high-risk exploration well with a well depth of 6410m and a maximum vertical depth of 4606m. It used 139.7mm casing cementing with casing reaching a depth of 6406.7m, setting a new record for the deepest horizontal well for shale gas in China. The bottom temperature was 151°C, and a high-density water-based cement slurry with a density of 2.21g/cm³ was returned to the wellhead. The overall well quality rate was 81.71%.

WG4 Well 139.7mm Single-Stage Full Cementing: Well depth 5555m, casing depth 5550m, bottom temperature 174°C. Low-density 1.45g/cm³ cement slurry was returned to the surface in a single operation, achieving high-quality cementing and setting a record for the largest temperature difference in the Huabei Oilfield.

Y101H88-1 Well 139.7mm Casing Cementing: Well depth 6265m, casing depth 6263m. The single-stage cementing section was 6265m long, and the bottom temperature was 151.4°C. Conventional-density cement slurry was used for cementing the horizontal section, and high-density water-based cement slurry with a density of 2.25g/cm³ was returned to the wellhead. The overall well quality rate was 86.2%.