Methods and apparatus for inspecting tubular goods using a continuous signal calibrating system

Claim 3

The method of claim 1 wherein said one radiation means is said radiation-detecting means.

Claim 4

The method of claim 1 wherein said tubular member is moved axially so that said different wall portions thereof are at longitudinally-spaced positions along the length of said tubular member.

Claim 5

The method of claim 3 wherein said one radiation means is said radiation-detecting means and said radiation-detecting means include a radiation detector adapted to be inserted into said tubular member for intercepting said beam of radiation upon rotation of said radiation-emitting means about said tubular member; and further including the step of rotating said radiation-emitting means about said tubular member as said tubular member is moved axially so that said successive signals are respectively representative of the attenuation by different wall portions of said tubular member disposed along a generally-helical path therealong.

Claim 6

Apparatus adapted for measuring the thickness of a test member comprising: radiation-emitting means adapted for directing a beam of radiation along a selected axis; radiation-detecting means including a radiation detector positioned on said axis for receiving said beam of radiation and adapted for producing signals representative of the intensity of radiation received by said radiation detector; controlling means including a member having a radiation-attenuating portion of known thickness adapted for movement into and out of said beam of radiation between said radiation-emitting means and said radiation detector; and signal-comparing means operatively coupled to said radiation detector and adapted for comparing first signals produced thereby when only said radiation-attenuating portion is intersected by said beam of radiation with second signals produced by said dEtector when only a test member of an unknown thickness is intersected by said beam of radiation, said signal-comparing means including means coupled to said radiation detector and adapted for storing said first signals as said first signals are being produced, and means coupled to said radiation detector and to said signal-storing means and adapted for combining said first signals with said second signals as said second signals are being produced to produce third signals representative of the difference between said known thickness and the thickness of a test member subsequently interposed between said radiation detector and said radiation-emitting means.

Claim 7

Apparatus adapted for measuring the thickness of a test member comprising: radiation-emitting means adapted for directing a beam of radiation along a selected axis; radiation-detecting means including a radiation detector positioned on said axis for receiving said beam of radiation and adapted for producing signals representative of the intensity of radiation received by said radiation detector; controlling means including a member having a radiation-attenuating portion of known thickness adapted for movement into and out of said beam of radiation between said radiation-emitting means and said radiation detector; and signal-comparing means operatively coupled to said radiation detector and adapted for comparing first signals produced thereby when only said radiation-attenuating portion is intersected by said beam of radiation with second signals produced by said dEtector when only a test member of an unknown thickness is intersected by said beam of radiation, said signal-comparing means including means coupled to said radiation detector and adapted for storing said first signals as said first signals are being produced, and means coupled to said radiation detector and to said signal-storing means and adapted for combining said first signals with said second signals as said second signals are being produced to produce third signals representative of the difference between said known thickness and the thickness of a test member subsequently interposed between said radiation detector and said radiation-emitting means.

Claim 8

The apparatus of claim 5 further including: clamping means selectively operable for releasably securing said radiation detector in a known position in relation to said radiation-emitting means when said first signals are being produced.

Claim 9

The apparatus of claim 5 further including: means adapted for moving a test member relative to said radiation detector and said radiation-emitting means for obtaining a series of said second signals respectively representative of the radiation attenuation produced by successive portions of such a test member for comparison with said first signals.

Claim 10

The apparatus of claim 7 wherein said moving means are adapted for moving a test member into and out of positions between said radiation detector and said radiation-emitting means to obtain said second signals.

Claim 11

The apparatus of claim 7 wherein said moving means are adapted for moving one of said radiation means in relation to the other of said radiation means and a test member interposed therebetween to obtain said second signals.

Claim 12

The apparatus of claim 9 wherein said one radiation means is said radiation-emitting means.

Claim 13

Apparatus adapted for measuring the wall thickness of an elongated tubular member comprising: radiation-detecting means including a radiation detector adapted for insertion into a tubular member to receive radiation directed laterally therethrough; radiation-emitting means spaced from said radiation detector and operatively arranged for directing a beam of radiation theretoward; radiation-controlling means including a movable member having a first portion of a known thickness adapted for interposition between said radiation-emitting means and said radiation detector to attenuate said beam of radiation to a selected intensity and a second portion having a radiation passage therein adapted for passing said beam of radiation, and means adapted for selectively shifting said movable member between first and second positions to respectively position said first and second portions in said beam of radiation; first signal means coupled to said radiation detector and operable when only said first portion of said movable member is positioned in said beam of radiation for producing a first signal representative of said known thickness and storing said first signal as said first signal is being produced; second signal means coupled to said radiation detector and operable only when said radiation passage is positioned in said beam of radiation and said radiation detector is inserted into a tubular member for producing a second signal representative of the wall thickness thereof; signal-comparing means operatively coupled to said first and second signal means and adapted for combining said stored first signal and said second signal as said second signal is being produced to produce a third signal representative of the difference between said known thickness and the wall thickness of a tubular member disposed over said radiation detector; and means operable only upon insertion of said radiation detector into a tubular member for shifting said movable member from its said first position to its said second position.

Claim 14

Apparatus adapted for measuring the wall thickness of an elongated tubular member comprising: radiation-detecting means including a radiation detector adapted for insertion into a tubular member to receive radiation directed laterally therethrough; radiation-emitting means spaced from said radiation detector and operatively arranged for directing a beam of radiation theretoward; radiation-controlling means including a movable member having a first portion of a known thickness adapted for interposition between said radiation-emitting means and said radiation detector to attenuate said beam of radiation to a selected intensity and a second portion having a radiation passage therein adapted for passing said beam of radiation, and means adapted for selectively shifting said movable member between first and second positions to respectively position said first and second portions in said beam of radiation; first signal means coupled to said radiation detector and operable when only said first portion of said movable member is positioned in said beam of radiation for producing a first signal representative of said known thickness and storing said first signal as said first signal is being produced; second signal means coupled to said radiation detector and operable only when said radiation passage is positioned in said beam of radiation and said radiation detector is inserted into a tubular member for producing a second signal representative of the wall thickness thereof; signal-comparing means operatively coupled to said first and second signal means and adapted for combining said stored first signal and said second signal as said second signal is being produced to produce a third signal representative of the difference between said known thickness and the wall thickness of a tubular member disposed over said radiation detector; and means operable only upon insertion of said radiation detector into a tubular member for shifting said movable member from its said first position to its said second position.

Claim 15

The apparatus of claim 11 further including: means adapted for axially moving a tubular member back and forth in relation to said radiation detector to obtain a series of said second Signals respectively representative of the wall thicknesses of successive portions of such a tubular member so that said signal-comparing means will combine said first and second signals to produce said third signals for measuring the differences between said known thickness and the wall thicknesses of successive portions of a tubular member moving over said radiation detector.

Claim 16

The apparatus of claim 12 wherein said radiation detector is responsive to radiation imposed thereon from any lateral direction thereabout and further including: means coupled to said radiation-emitting means and operatively arranged and adapted for rotating said radiation-emitting means about said radiation detector for directing a lateral beam of radiation theretoward whenever a tubular member is disposed over said radiation detector so that said third signals will be respectively representative of the differences between said known thickness and the wall thickness of successive helically-distributed portions of a tubular member moving over said radiation detector.

Claim 17

The apparatus of claim 13 further including: clamping means selectively operable for releasably securing said radiation detector in a known position in relation to said radiation-emitting means when said first signals are being produced.