Patents
US 8201644 B2: Dual pipe for increased fluid flow
- Granted
- 2012-06-19
- Filed
- 2009-02-23 application 12391113
- Type
- Utility · 19 claims
- Elsewhere
- Google Patents ↗ · USPTO patent document ↗ · USPTO Patent Center record ↗
Abstract
A dual pipe drill string system having increased fluid flow. The dual pipe system comprises a plurality of pipe sections, each pipe section having an inner rod and an outer pipe. The inner rod and the outer pipe of each pipe section may be coupled to the inner rod and outer pipe of an adjacent pipe section. An annulus between the inner rod and the outer pipe defines a fluid flow path through the dual pipe system. The outer pipe defines a shoulder at each end of an individual pipe section. The inner rod defines at least one stop for maintaining the inner rod within the outer pipe. A spacing assembly disposed around the circumference of the inner rod defines paths for fluid flow and maintains a minimum distance between the stop and the shoulder at one end of outer pipe of the pipe section.
Source: PVGPATDIS, file of 2026-04-10 (ipg120619.xml).
Assignees
| Assignee | Type | Place | Also on furp.org | Source |
|---|---|---|---|---|
| The Charles Machines Works, Inc. 255 patents | US company or organization | Perry, OK | PVGPATDIS, file of 2026-04-10 |
Inventors
| Inventor | Place | Patents | Person page | Source |
|---|---|---|---|---|
| Adam R. Hall | Perry, OK | 9 | PVGPATDIS, file of 2026-04-10 | |
| Richard F. Sharp | Perry, OK | 9 | PVGPATDIS, file of 2026-04-10 |
CPC categories
| Subclass | Category | First group | Source |
|---|---|---|---|
| E21B | Earth or rock drilling; obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells | E21B17/18 | PVGPATDIS, file of 2026-04-10 |
Cooperative Patent Classification, as currently assigned (one row per subclass).
Assignments and security interests
| Recorded | What | From | To | Reel/frame | Source |
|---|---|---|---|---|---|
| 2009-02-26 | Assignment Assignment of assignor's interest | HALL, ADAM R. signed 2009-01-30 SHARP, RICHARD F. signed 2009-01-30 | THE CHARLES MACHINE WORKS, INC. PERRY, OK | 22316/922 | ECORSEXC, file of 2026-09-25 |
Documents recorded with the USPTO Assignment Recordation Branch that list this patent. A security interest is a lender’s claim on the patent as collateral; a release ends it.
USPTO bulk data: PatentsView granted patents, disambiguated (PVGPATDIS) for patents, assignees, inventors, places and CPC categories; the USPTO Patent Assignment Dataset (ECORSEXC) for assignments and security interests. Patents filed in the last 20 years. No claims or full text. Links to other records are by name (and state): EXACT means the identical full name and state; FUZZY means a looser name match, with the confidence shown.