Title:
Well drilling plug with mandrel formed from degradable material
Document Type and Number:
Japanese Patent JP6327946
Kind Code:
B2
Abstract:
A plug for well drilling process comprising: (a) a mandrel formed from a degradable material; (b) a pair of rings placed on an outer peripheral surface existing in the orthogonal to an axial direction of the mandrel, at least one of the rings being formed from a degradable material; and (c) at least one diameter-expandable circular rubber member placed at a position between the pair of rings on the outer peripheral surface existing in the orthogonal to the axial direction of the mandrel; the percentage of mass loss in the degradable material after immersion for 72 hours in water at a temperature of 150°C preferably being from 5 to 100%; and a well drilling method comprising the step of plugging well hole using the plug for well drilling process , wherein part or all of the plug for well drilling process degrades after the plugging.
Inventors:
Masayuki Okura
High Takeo Hashi
High Takeo Hashi
Application Number:
JP2014109013A
Publication Date:
May 23, 2018
Filing Date:
May 27, 2014
Export Citation:
Assignee:
Kureha Co., Ltd.
International Classes:
E21B43/16
Domestic Patent References:
| JP2011256221A | ||||
| JP4179792A |
Foreign References:
| US20120031626 | ||||
| US20050205266 |
Attorney, Agent or Firm:
Harakenzo world patent & trademark