One-trip multi-zone gravel pack system is used for the oil&gas wells with multiple perforated zones with each zone requiring gravel pack.
The process can be one-time trip in multi-zone service tools, zone-by-zone setting, pack, sealing and isolating to prevent leaking, realizing one-trip multi-zone unequal distance net pay gravel pack operations, greatly reducing well completion time.
• One-trip string, realizing packer setting and each-zone separated pack for single-well multi-zones, high operation efficiency.
• One-trip string for multiple sand-control service.
• Locating tool for the pack ,preventing string moving during pack.
• Isolation between layers when pack, preventing completion fluid leaking.
• Examination after every-layer pack, repack if necessary.
Wellbore tool string structure
top packer + pack off Assembly + sealing tub + upper extension +pack sliding sleeve + lower extension + collar locator + sand screen/blank pipe + isolation packer + upper extension + pack sliding sleeve + lower extension + collar locator+ sand screen/blank pipe +snap latch + sump packer.
The string uses ACME thread connecting with higher joint strength besides using LTC casing thread, and the tool surface location uses contour localization, having the function to prevent tool rotating and to assist sealing.
Service tool string structure
Setting tool + pack off + 4"&2-7/8"wash pipe + middle seal + GP Tool + MARS valve + load indicator + one way tool + two way tool + lower seal. Mostly using tougue&groove system+ O-ring to connect tools, reducing wall thickness, increasing the insider/outsider diameter, higher joint strength; commonly using contour localization for the tool surface location, functioning in preventing tool rotating and assisting sealing.
