Patent · US Expired

Process for hydraulically fracturing oil and gas wells

US6446727B1 · kind B1 · utility

139Cited by
21References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1999
Grant dateSep 10, 2002
Priority date
Expiry dateJan 29, 2019

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B43/26
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A wellbore (10) in an earth formation (12) having a casing (14) and a plurality of pay or production zones (32, 34, 36) provided in the formation. A coiled tubing string (18) from a reel (20) is injected by an injector (24) into the wellbore (10) for first perforating casing section (38) at each pay zone (32, 34, 36) in a single pass of the coiled tubing (18) as shown in FIG. 1. Next, the coiled tubing (18) is utilized for hydraulic fracturing each of the pay zones (32, 34, 36) individually from the lowermost pay zone (32) to the uppermost pay zone (36) in a single pass of the coiled tubing (18). Each pay zone (32, 34, 36) is isolated for the hydraulic fracturing. An upper packer (44 or 54) is provided above each of the pay zones for isolation and a lower packer (56) or sand plug (50) is utilized for isolating the lower or outermost end of each pay zone (32, 34, 36). Swab cups (58, 54A, 56A, 54B, 56B) are also utilized for isolation of pay zones.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.