Ultrasonic testing method and manufacturing method of seamless pipe or tube
View Patent ↗A circumferential angle of incidence αi of an ultrasonic wave transmitted from an ultrasonic probe 1 upon a tubular test object P and an axial angle of incidence βi of the ultrasonic wave transmitted from the ultrasonic probe 1 upon the tubular test object P are set based on a ratio of thickness to outer diameter t/D of the tubular test object P so that an internal refraction angle θk calculated from the circumferential angle of incidence αi, the axial angle of incidence βi, and the ratio of thickness to outer diameter t/D of the tubular test object may be not less than 35° and not more than 60°.
1. A method for performing ultrasonic testing comprising the steps of:
arranging an ultrasonic probe which comes in an ultrasonic phased array probe in which a plurality of transducers are arrayed so as to face an external surface of a tubular test object;
setting a circumferential angle of incidence αi of an ultrasonic wave to be transmitted from said ultrasonic probe upon said tubular test object and an axial angle of incidence βi of the ultrasonic wave to be transmitted from said ultrasonic probe upon said tubular test object based on a ratio of thickness to outer diameter t/D of said tubular test object so that an internal refraction angle θk calculated from said circumferential angle of incidence αi, said axial angle of incidence βi, and said ratio of thickness to outer diameter t/D of the tubular test object may be not less than 35° and not more than 60°;
transmitting an ultrasonic wave to said tubular test object from said ultrasonic probe in which said circumferential angle of incidence αi and said axial angle of incidence βi are set;
receiving an ultrasonic wave reflected from said tubular test object by said ultrasonic probe; and
processing the received ultrasonic wave to detect a flaw on said tubular test object,
wherein in the step of setting said circumferential angle of incidence αi and said axial angle of incidence βi, by electrically controlling transmission time-shift or reception time-shift of an ultrasonic wave by said plurality of transducers, at least one of said circumferential angle of incidence αi and said axial angle of incidence βi of the ultrasonic wave transmitted to said tubular test object is electrically adjusted.
2. A method for manufacturing a seamless pipe or tube, comprising:
a first step of piercing a billet to manufacture a seamless pipe or tube; and
a second step of detecting a flaw in the seamless pipe or tube manufactured by said first step, by using the ultrasonic testing method according to claim 1 .
3. The ultrasonic testing method according to claim 1 , wherein
in the step of setting said circumferential angle of incidence αi and said axial angle of incidence βi, said circumferential angle of incidence αi and said axial angle of incidence βi are set so that a propagation direction of an ultrasonic wave made incident upon said tubular test object calculated from said circumferential angle of incidence αi and said axial angle of incidence βi may be substantially orthogonal to an extension direction of a flaw to be detected, and then at least one of said circumferential angle of incidence αi and said axial angle of incidence βi is electrically adjusted so that said internal refraction angle θk may be not less than 35° and not more than 60°.
4. A method for performing ultrasonic testing comprising the steps of:
arranging an ultrasonic probe so as to face an external surface of a tubular test object;
setting a circumferential angle of incidence αi of an ultrasonic wave to be transmitted from said ultrasonic probe upon said tubular test object and an axial angle of incidence βi of the ultrasonic wave to be transmitted from said ultrasonic probe upon said tubular test object based on a ratio of thickness to outer diameter t/D of said tubular test object so that an internal refraction angle θk calculated from said circumferential angle of incidence αi, said axial angle of incidence βi, and said ratio of thickness to outer diameter t/D of the tubular test object may be not less than 35° and not more than 60°;
transmitting an ultrasonic wave to said tubular test object from said ultrasonic probe in which said circumferential angle of incidence αi and said axial angle of incidence βi are set;
receiving an ultrasonic wave reflected from said tubular test object by said ultrasonic probe; and
processing the received ultrasonic wave to detect a flaw on said tubular test object,
wherein in the step of setting said circumferential angle of incidence αi and said axial angle of incidence βi, positioning said ultrasonic probe so as to obtain said circumferential angle of incidence αi and said axial angle of incidence βi for which said internal refraction angle θk calculated by the following Equation (1) may be not less than 35° and not more than 60°:
θ k =cos −1 (cos θ r ·cos φ−sin θ r ·cos γ·sin φ) (1)
where a propagation angle γ, an external angle θr, and an angle φ are given by the following equations (2) through (4) respectively:
γ
=
tan
-
1
(
sin
β
i
cos
β
i
·
sin
α
i
)
(
2
)
θ
r
=
sin
-
1
(
[
(
Vs
/
Vi
)
2
·
(
sin
2
β
i
+
cos
2
β
i
-
sin
2
α
i
)
]
1
/
2
)
(
3
)
ϕ
=
sim
-
1
(
k
·
sin
θ
′
)
-
θ
′
(
4
)
where, in the above Equation (3), Vs refers to a propagation speed of an ultrasonic wave propagating through the tubular test object and Vi refers to a propagation speed of the ultrasonic wave in a coupling medium that fills a gap between the ultrasonic probe and the tubular test object, k and θ′ in the above equation (4) are given by the following Equations (5) and (6) respectively:
k
=
1
1
-
2
(
t
/
D
)
(
5
)
tan
θ
′
=
cos
γ
·
tan
θ
r
.
(
6
)
5. The ultrasonic testing method according to claim 4 , wherein
in the step of setting said circumferential angle of incidence αi and said axial angle of incidence βi, said circumferential angle of incidence αi and said axial angle of incidence βi are set so that a propagation direction of an ultrasonic wave made incident upon said tubular test object calculated from said circumferential angle of incidence αi and said axial angle of incidence βi may be substantially orthogonal to an extension direction of a flaw to be detected, and then at least one of said circumferential angle of incidence αi and said axial angle of incidence βi is adjusted so that said internal refraction angle θk may be not less than 35° and not more than 60°.
6. A method for manufacturing a seamless pipe or tube, comprising:
a first step of piercing a billet to manufacture a seamless pipe or tube; and
a second step of detecting a flaw in the seamless pipe or tube manufactured by said first step, by using the ultrasonic testing method according to claim 4 .
7. A method for performing ultrasonic testing comprising the steps of:
arranging an ultrasonic probe so as to face an external surface of a tubular test object;
setting an angle of incidence θw of an ultrasonic wave to be transmitted from said ultrasonic probe upon said tubular test object and a propagation angle γ of the ultrasonic wave to be made incident upon said tubular test object based on a ratio of thickness to outer diameter t/D of said tubular test object so that an internal refraction angle θk calculated from said angle of incidence θw, said propagation angle γ, and the ratio of thickness to outer diameter t/D of said tubular test object may be not less than 35° and not more than 60°;
transmitting an ultrasonic wave to said tubular test object from said ultrasonic probe in which said angle of incidence θw and propagation angle γ are set;
receiving an ultrasonic wave reflected from said tubular test object by said ultrasonic probe; and
processing the received ultrasonic wave to detect a flaw on said tubular test object,
wherein the step of setting said angle of incidence θw and said propagation angle γ, positioning said ultrasonic probe so as to obtain said angle of incidence θw and propagation angle γ for which said internal refraction angle θk is calculated by the following Equation (1) may be not less than 35° and not more than 60°:
θ k =cos −1 (cos θ r ·cos φ−sin θ r ·cos γ·sin φ) (1)
where an external refraction angle θr and an angle φ in the above Equation (1) are given by the following Equations (7) and (4) respectively:
sin θ r=Vs/Vi ·sin θ w (7)
φ=sin −1 ( k ·sin θ′)−θ′ (4)
where, in the above Equation (7), Vs refers to a propagation speed of an ultrasonic wave propagating through the tubular test object and Vi refers to a propagation speed of the ultrasonic wave in coupling medium that fills gap between the ultrasonic probe and the tubular test object, and k and θ′ in the above Equation (4) are given by the following Equations (5) and (6) respectively
k
=
1
1
-
2
(
t
/
D
)
(
5
)
tan
θ
′
=
cos
γ
·
tan
θ
r
.
(
6
)
8. A method for manufacturing a seamless pipe or tube, comprising:
a first step of piercing a billet to manufacture a seamless pipe or tube; and
a second step of detecting a flaw in the seamless pipe or tube manufactured by said first step, by using the ultrasonic testing method according to claim 7 .
9. The ultrasonic testing method according to claim 7 , wherein
in the step of setting said angle of incidence θw and said propagation angle γ, said propagation angle γ is set so that a propagation direction of an ultrasonic wave made incident upon said tubular test object may be substantially orthogonal to an extension direction of a flaw to be detected, and then said angle of incidence θw is adjusted so that said internal refraction angle θk may be not less than 35° and not more than 60°.