GB2180575A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
Stabilizer for drillstems
Assignee: Gulf Canada Ltd
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Filing: 1986-09-08
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Granted: —
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Expires: 2006-09-08
Abstract
Abstract An improved stabilizer (1) for use in stabilizing both drill collars and other sections on a drill string is disclosed. The stabilizer has at least three circumferentially spaced helical blades (2) which have a tapered portion (3,4) at each end and a cylindrical portion (5) therebetween, each blade overlapping the adjacent blade within each tapered portion as well as within the cylindrical portion. <IMAGE>
Inventors
- 👤 Stuart D Butler
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-10-23 04:09
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1078; E21B17/22
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
93 words
A drillstem stabilizer comprising:
(a) at least three circumferentially spaced helical stabilizing blades each having leading and trailing ends, each pair of adjacent blades defining a groove therebetween,
(b) a tapered blade portion at each leading and trailing end sufficiently long to bear a transverse load, said leading tapered blade portion and trailing tapered blade portion being separated by a cylindrical blade portion of a length at least one-half the overall diameter of said stabilizer including said blades, wherein each of said blades overlaps an adjacent blade within each of said tapered portions.
Claim 2
Dependent Claim
93 words
A drillstem stabilizer comprising:
(a) at least three circumferentially spaced helical stabilizing blades each having leading and trailing ends, each pair of adjacent blades defining a groove therebetween,
(b) a tapered blade portion at each leading and trailing end sufficiently long to bear a transverse load, said leading tapered blade portion and trailing tapered blade portion being separated by a cylindrical blade portion of a length at least one-half the overall diameter of said stabilizer including said blades, wherein each of said blades overlaps an adjacent blade within each of said tapered portions.
Claim 3
Dependent Claim
14 words
A stabilizer as claimed in Claim 1, wherein said tapered portions are substantially frustoconical.
Claim 4
Dependent Claim
30 words
A stabilizer as claimed in Claim 2, wherein the cone angle of said frustoconical tapered portions is adapted to spread said transverse load along the length of each tapered portion.
Claim 5
Dependent Claim
15 words
A stabilizer as claimed in Claim 1, wherein said tapered portions are arcuate in outline.
Claim 6
Dependent Claim
40 words
A stabilizer as claimed in Claim 1, wherein the angular position of each of said grooves at one end of said stabilizer is displaced substantially 180 from the circumferential position of a blade at the opposite end of said stabilizer.
Claim 7
Dependent Claim
30 words
A stabilizer as claimed in Claim 1, wherein the width of said blades at the outside diameter thereof is at least equal to the width of grooves between said blades.
Claim 8
Dependent Claim
17 words
A stabilizer as claimed in Claim 1, having at least three and no more than seven blades.
Claim 9
Dependent Claim
16 words
A stabilizer as claimed in Claim 1 wherein said tapered blade portions are of equal length.
Claim 10
Dependent Claim
25 words
A stabilizer as claimed in Claim 4 wherein each of said tapered blade portions is at least one-third as long as said cylindrical blade portion.
Claim 11
Dependent Claim
34 words
A stabilizer as claimed in Claim 1 wherein the width of each groove at the base of said blades is less than the width of said groove at the peripheral surface of said blades.
Claim 12
Dependent Claim
22 words
A stabilizer as claimed in claim 1 and substantially as hereinbefore described with reference to, and as shown in the accompanying drawings.
References Cited (Backward Citations)
No citation records indexed.
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