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US3902249A Expired / Lapsed US ⏱️ 0.0 years remaining

Calipers

Assignee: Smith International Inc
•
Filing: 1973-06-28
•
Granted: 1975-09-02
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Expires: 1993-06-28
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Abstract

Abstract A drill pipe calipering apparatus includes two hand held calipers for calipering the pin and box tool joints, an automatic caliper through which the pipe is fed to caliper the tube, bridge circuit means to convert caliper position to a proportional voltage, and a console whereat maximum departure from a preset nominal of pin, box and tube diameters are digitally displayed together with grade-indicators respecting pin, box and tube, there being telemetering means to signal between the hand held calipers and console to advise the operators when the console is clear to receive information and when it is in a hold condition unreceptive to further information. The automatic caliper is associated with the floating head of a magnetic flaw detector.

Inventors

  • 👤 Joseph Wm Mcclughan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 04:30
CPC Classifications
G; G01; G01B; G01B3/00; G01B3/22; G01B3/24; G01B7/00; G01B7/12; G01B7/125

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 240 words
In drill pipe calipering apparatus having hand held calipering means for manually calipering at least one tool joint and producing a first electrical current having an amplitude that is a function of said joint''s external diameter, automatic caliper means for automatically calipering a tube passed therethrough and producing a second electrical current having an amplitude that is a function of said tube''s external diameter, and transmission means for transmitting said first and second electrical currents from the hand held and automatic caliper means to a processing means for producing a plurality of displays dependent on the amptitude of said first and second electrical currents respectfully received from said calipering means and said caliper means, said processing means including means to indicate the maximum differences between the external diameters of the tube and joint and respective preset nominal tube and joint diameters and including means to indicate the grades of the pipe joint and tube when said differences from said nominal diameters lies within a particular range the improvement comprising: first switch means located on each of said hand held calipering means and automatic caliper means for terminating the flow of said first and second electrical currents from said calipering means and said caliper means to said processing means and placing said processing means in condition to continuously produce said plurality of displays dependent on the amplitude of said electrical currents received immediately prior to said termination of said current flow.
Claim 2
Dependent Claim 240 words
In drill pipe calipering apparatus having hand held calipering means for manually calipering at least one tool joint and producing a first electrical current having an amplitude that is a function of said joint''s external diameter, automatic caliper means for automatically calipering a tube passed therethrough and producing a second electrical current having an amplitude that is a function of said tube''s external diameter, and transmission means for transmitting said first and second electrical currents from the hand held and automatic caliper means to a processing means for producing a plurality of displays dependent on the amptitude of said first and second electrical currents respectfully received from said calipering means and said caliper means, said processing means including means to indicate the maximum differences between the external diameters of the tube and joint and respective preset nominal tube and joint diameters and including means to indicate the grades of the pipe joint and tube when said differences from said nominal diameters lies within a particular range the improvement comprising: first switch means located on each of said hand held calipering means and automatic caliper means for terminating the flow of said first and second electrical currents from said calipering means and said caliper means to said processing means and placing said processing means in condition to continuously produce said plurality of displays dependent on the amplitude of said electrical currents received immediately prior to said termination of said current flow.
Claim 3
Dependent Claim 68 words
Apparatus according to claim 1 wherein said improvement includes a second switch means located at said processing means for placing the processing means in condition to receive and process further flow of said first and second electrical currents from said calipering means and said caliper means and to produce said plurality of displays dependent of the amplitude on said further flow of said first and second electrical currents.
Claim 4
Dependent Claim 60 words
Apparatus according to claim 2 wherein the improvement includes indicator means physically mounted adjacent said first switch means on a manually operable portion of said hand held caliper means and is electrically connected to said processing means such that actuation of said second switch means at said processing means causes said indicator to indicate the condition of the processing means.
Claim 5
Dependent Claim 63 words
Apparatus according to claim 3 wherein the hand held calipering means comprise an L shaped body, an L shaped gage member inverted with respect to and adjustably secured to said body, and including a reference surface in opposition to the lower portion of said L shaped body, and a potentiometer having its moving contact actuator projecting through the body toward said reference surface.
Claim 6
Dependent Claim 41 words
Apparatus according to claim 4 wherein said manually operable portion of said hand held calipers means comprises an L shaped handle attached to said body, and said transmission means is an electric cable extending from said body to said processing means.
Claim 7
Dependent Claim 29 words
Apparatus according to claim 5 wherein said first switch means is mounted on said handle and selectably controls the flow of said first electrical current through said electric cable.
Claim 8
Dependent Claim 34 words
Apparatus according to claim 6 wherein the hand held caliper means are two in number, one to be used for calipering tool joint pins and one to be used for calipering tool joint boxes.

References Cited (Backward Citations)

US2403896A Cited
US2810200A Cited
US3007252A Cited
US3042909A Cited
US3103072A Cited
US3169323A Cited
US3500547A Cited
US3513553A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-09-01 1979-03-03 1979-09-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-09-01 1983-03-03 1983-09-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-09-01 1987-03-03 1987-09-02 $7700.00 Window Closed / Lapsed

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