The invention discloses a surface wave detection method for a longitudinal defect on the outer surface of a small-diameter tube The method comprises the following steps: 1), cleaning the outer surface of a to-be-detected small-diameter tube and coating the small-diameter tube with a coupling agent; 2), arranging a surface wave probe on the to-be-detected small-diameter tube; 3), selecting a comparison test cube of the to-be-detected small-diameter tube and cutting a groove in the surface of the comparison test cube of the to-be-detected small-diameter tube; 4) using the comparison test cube of the to-be-detected small-diameter tube to perform horizontal line calibration on an ultrasonic instrument; 5), adjusting the detection sensitivity of the ultrasonic instrument; 6), adjusting the ultrasonic instrument to enable the propagating direction of surface waves emitted by the surface wave probe to be perpendicular to a bus-bar of the to-be-detected small-diameter tube, and using the surface wave probe for scanning on two side surfaces of the to-be-detected small-diameter tube sequentially; determining that a surface longitudinal defect with the depth larger than A mm is formed in the current detection position of the to-be-detected small-diameter tube when reflected waves with the wave amplitude higher than B% are fully displayed on a display screen of the ultrasonic instrument According to the surface wave detection method, detection of the longitudinal defect on the surface of the small-diameter tube can be realized, and the defect can be positioned accurately

Surface wave detection method for longitudinal defect on outer surface of small-diameter tube

A pipe flaw guided circumferential wave nondestructive testing method based on transverse-wave straight probes comprises the following steps: building transverse-wave straight probes in a pipe to excite a guided circumferential wave flaw detector; apply numerical calculation software to drawing guided circumferential wave dispersion curves of the pipe; selecting an excitation frequency suitable for pipe flaw nondestructive detection; drawing wave structure charts of all guided circumferential wave modes under the frequency to determine excitation methods of the corresponding guided circumferential wave modes and the relationships between the arrangement directions of the transverse-wave straight probes and guided circumferential wave excitation typical modes; and exciting guided circumferential waves, receiving flaw echoes of the guided circumferential waves, and determining the pipe flaw positions by analyzing the time at which reflection echoes in received signals reach a receiving point.

Pipe flaw guided circumferential wave nondestructive testing method based on transverse-wave straight probes

The invention relates to a special test block for ultrasonic phased array detection small diameter tube butt weld The special test block comprises a test block, an angle compensation cambered surface, a resolution test arc-shaped hole group, a TCG correction hole group, a dovetail groove, a primary reflected wave bottom surface scattering correction theta1 hole and an fillet weld position and sensitivity contrast theta1 hole, wherein the angle compensation cambered surface, the resolution test arc-shaped hole group, the TCG correction hole group, the dovetail groove, the primary reflected wave bottom surface scattering correction theta1 hole and the fillet weld position and sensitivity contrast theta1 hole are disposed in the test block The special test block can perform instrument adjustment, defect contrast and detection system verification and have the advantages of being high in efficiency and low in cost and capable of providing defect verification of key parts and the like

Special test block for ultrasonic phased array detection small diameter tube butt weld

The invention discloses a transverse wave couplant for power station boiler steel pipe inner wall oxide-film high frequency ultrasonic measurement, and a preparation method thereof. The transverse wave couplant is prepared by honey and a mixture of one or more than one carbohydrate. Compared with the prior art, the transverse wave couplant has the advantages of: (1) cheap and easily available raw material: most common carbohydrate in the market; (2) easy cleaning: compared with a common machine oil industrial couplant, the transverse wave couplant can be cleaned only by water flushing or paper towel wiping; (3) pure natural raw material which has no poisonous effects and possesses high safety; (4) neutrality: the transverse wave couplant is difficult to corrode an ultrasonic transducer and an object for measurement, and has a wider application scope; (5) viscosity greater than 300mpa: the transverse wave couplant is suitable for various supersonic reflectoscopes; and (6) sound detection effect: the transverse wave couplant is innovative at home, greatly accelerates domestic ultrasonic wave transverse wave detection development, and has high market values and bright application prospects.

Transverse wave couplant for power station boiler steel pipe inner wall oxide-film high frequency ultrasonic measurement, and preparation method thereof

The invention provides an ultrasonic lap weld detection composite probe for oil and gas transportation steel pipelines The composite probe is such structured that a left bracket (1) and a right bracket (2) are arranged in parallel, a bolt (25) and a nut (26) connect the left bracket (1) with the right bracket (2), the left bracket (1) is located below the right bracket (2), the left bracket (1) and the right bracket (2) respectively fix a second organic glass block (4) and a first organic glass block (2), the central parts of the second organic glass block (4) and the first organic glass block (3) respectively fix a second longitudinal wave normal probe (6), a third longitudinal wave normal probe (7) and a first longitudinal wave normal probe (5), and the second longitudinal wave normal probe (6), the third longitudinal wave normal probe (7) and the first longitudinal wave normal probe (5) are connected with a single-channel dual-function circuit The ultrasonic lap weld detection composite probe has high detection accuracy and a high detection rate and meets requirements of fillet weld detection

Ultrasonic lap weld detection composite probe

The invention relates to a method for measuring thicknesses of a metal layer and an oxide layer of the wall of a boiler heating surface tube. A high-frequency ultrasonic pulse generating/receiving unit is used for motivating a probe to generate ultrasonic waves and receive reflected signals from the probe, and a broadband oscilloscope displays the ultrasonic signals. The method includes connecting the high-frequency ultrasonic pulse generating/receiving unit, the broadband oscilloscope and a high-frequency transverse wave normal probe, and adjusting instrument parameters; polishing the surface of the heating surface tube to be measured and coating a couplant; placing the high-frequency transverse wave normal probe on the surface of the heating surface tube to be measured and starting an instrument for measurement; adjusting the time base proportion and gain of the broadband oscilloscope, displayed ultrasonic echo signals and time intervals; and calculating the thickness S1 of the metal layer of the tube wall and the thickness S2 of the oxide layer of the tube wall. According to the measuring method, reflected signals of the oxide layer/metal base interface are distinguished clearly, the thicknesses of the metal layer and the oxide layer of the wall of the boiler heating surface tube are measured accurately, the detecting accuracy is high, the operation is simple and convenient, and accurate data are provided for production operation and equipment maintenance.

Method for measuring thicknesses of metal layer and oxide layer of wall of boiler heating surface tube

The utility model discloses a compound probe for detecting defects of weld joints of workpieces. The compound probe comprises a long cylindrical shell. An organic glass wedge is arranged in the middle of the shell, a damping block is arranged on the periphery of the organic glass wedge and is positioned in the shell, an inclined TOFD (time of flight diffraction) chip, a common pulse reflection ultrasonic chip a and a common pulse reflection ultrasonic chip b are sequentially inlaid on the organic glass wedge from the right end to the left end of the organic glass wedge, and a power line and a power line port which are used for being connected with a piezoelectric chip are arranged at the left end of the shell. The TOFD chip and the common pulse reflection ultrasonic chips are combined to form the TOFD and common pulse reflection ultrasonic compound probe, the interlayer defects of the weld joints are accurately positioned by the TOFD chip, regions of upper and lower surfaces of the weld joints are detected by a common pulse reflection ultrasonic probe, and the problem of surface 'dead zones' in the TOFD detection technology can be solved.

Compound probe for detecting defects of weld joints of workpieces

The invention discloses a measuring method for delay and leading edge of a sound-transmission-wedge surface wave probe. The measuring method is completed by the assistance of a test block, wherein the material of the test block is same as that of a sound-transmission inclined wedge, and the shape of the test block is that a circular-arc-shaped bottom surface is arranged at one end of the a cuboid. The measuring method comprises the steps of 1) connecting a surface wave probe with an ultrasonic flaw detector, then arranging the surface wave probe on the upper surface of the test block, moving the surface wave probe forwardly and backwardly, and keeping the surface wave probe to be fixed when the longitudinal waves on the ultrasonic flaw detector obtains the highest reflection waves; 2) reading the time difference t1 between the transmission waves and the received reflection on the ultrasonic flaw detector; 3) calculating the transmission time of the ultrasonic waves in the test block; 4) calculating the delay t' of the test block; 5) measuring the horizontal distance M from the front end face of the surface wave probe to the circular arc of the test block by a steel ruler; and 6) calculating the leading edge l0 of the test block. According to the measuring method, the operation is simple and convenient, the error is small, and the delay and the leading edge of the sound-transmission-wedge surface wave probe can be measured accurately.

Measuring method for delay and leading edge of sound-transmission-wedge surface wave probe

The utility model relates to a device for measuring thicknesses of a metal layer and an oxide layer of a boiler heating surface tube wall. The device is composed of a high-frequency ultrasonic pulse generating/receiving unit, a broadband oscilloscope and a high-frequency transverse wave normal probe, wherein the high-frequency ultrasonic pulse generating/receiving unit is in circuit connection with the broadband oscilloscope and the high-frequency transverse wave normal probe respectively. The high-frequency transverse wave normal probe motivates and receives ultrasonic waves spread in workpieces when detecting the workpieces. The high-frequency ultrasonic pulse generating/receiving unit is in charge of motivating the probe to generate high-frequency narrow-pulse transverse wave ultrasonic signals and receiving feedback signals of the probe simultaneously. The broadband oscilloscope displays the ultrasonic signals, distinguishes reflected signals of an oxide/metal matrix interface and extracts time intervals between different reflected waves. By means of the device, the reflected signals of the oxide/metal matrix interface are distinguished clearly, thicknesses of the metal layer and the oxide layer of the boiler heating surface tube wall are measured accurately, the detection accuracy is high, the operation is simple and convenient, and accurate data are provided for production operation and maintenance of equipment.

Device for measuring thicknesses of metal layer and oxide layer of boiler heating surface tube wall

The utility model relates to a test block for small-diameter tube ultrasonic testing. The test block is a strip-shaped body, and is provided with a left side convex cambered surface, an outer side convex cambered surface, an outer side concave cambered surface, a U-shaped groove, an inner side concave cambered surface, an inner side convex cambered surface, a transverse through hole, stepped holes, a large V-shaped slot and a small V-shaped slot. The test block has multiple functions; various test data can be obtained in one test, so that the trouble of changing test blocks repeatedly for meeting testing requirements is avoided; the defect that the flaw of root of weld easily fails to be tested as inner and outer arc acoustic energy loss tests cannot be carried out in the prior art can be remedied.

Hao Xiaojun

Papers

Method for measuring thicknesses of metal layer and oxide layer of wall of boiler heating surface tube

Compound probe for detecting defects of weld joints of workpieces

Measuring method for delay and leading edge of sound-transmission-wedge surface wave probe

Device for measuring thicknesses of metal layer and oxide layer of boiler heating surface tube wall

Test block for small-diameter tube ultrasonic testing