Unconsolidated sand stabilization through wellbore stress state control
Two methods are presented for controlling wellbore stress state in order to stabilize unconsolidated sands. One method is the application of elevated drilling fluid weight to prevent dilation and/or shear/crushing of sand grains surrounding the wellbore. Instabilities resulting from such formation failure would be expected to increase the likelihood for sand production. Means are provided for determining mud weight required to avoid such failure. The second method suggests that there is an elevated range in stress state in which stable sand arches will form over perforations and permit unrestricted production flow rates from many wells without sand production. The method utilizes one or more inflatable external casing packer(s), opposite the interval(s) to be perforated, for establishing and maintaining the proper stress state for stable sand arches.
- OSTI ID:
- 7355753
- Report Number(s):
- CONF-750924-5
- Country of Publication:
- United States
- Language:
- English
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