The method of installing oil well casing mainly includes the following steps:
Preparation
Borehole Inspection: Check the wellbore’s diameter, depth, and stability to ensure they meet design requirements. Address issues like collapse or shrinkage before proceeding.
Casing Selection: Choose appropriate casing based on wellbore size, formation conditions, and mining requirements. Consider material, strength, and sealing properties.
Equipment Check: Inspect equipment such as drilling rigs and centralizers to ensure they are in good working condition.
Casing Operation
Handling & Storage: Transport and store casing carefully to avoid damage. Keep it in a flat, dry area to prevent rust and deformation.
Casing Connection: Connect the casing string using threaded connections or welding, ensuring tightness and proper sealing.
Lowering the Casing: Lower the connected casing string into the wellbore while keeping it vertical and controlling the speed to prevent damage.
Cementing Operation
Inject Cement Slurry: Pump cement slurry into the annular space between the casing and wellbore. Control the slurry’s density, flow rate, and pressure.
Displace Cement Slurry: Use drilling fluid or water to displace the cement slurry, maintaining stable pressure to avoid backflow.
Wait for Solidification: Allow the cement to solidify, typically for 24 to 48 hours, monitoring pressure and temperature during the wait.
Casing Quality Inspection
Pressure Test: After cementing, perform a pressure test to check the casing’s strength and sealing.
Ultrasonic Testing: Use ultrasonic technology to evaluate the bonding quality between the casing and cement.
Conclusion:
Proper preparation, installation, cementing, and quality inspection are critical to ensuring the oil well casing is installed safely and effectively.
