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Ultrasound flaw detection is a method to inspect the defect of a part by means of the reflection characteristics of the interface edge when the ultrasonic energy penetrates into the depth of the metal material and one section enters another section. When the ultrasonic beam passes from the surface of the part to the inside of the metal from the probe, the reflected waves will occur separately when the defect and the bottom of the part are encountered. Pulse waveforms are formed on the fluorescent screen, and the position and size of defects are judged according to these pulse waveforms. Eddy current detection is to use the principle of electromagnetic induction to excite the probe coil with the sinusoidal current. When the probe approaches the metal surface, the alternating magnetic field around the coil generates induced current on the metal surface. For flat metal, the flow direction of the induced current is a circle with concentric coils, similar to a vortex, called eddy current. At the same time, the eddy current also produces the same frequency magnetic field, which is opposite to the coil magnetic field.

The loss resistance of the eddy current channel and the reverse flux produced by the eddy current are reflected in the probe coil, which changes the current size and phase of the coil, that is, the impedance of the coil. Therefore, when the probe moves on the metal surface and encounters defects or changes in material and size, the eddy current magnetic field reacts differently to the coil, causing the coil impedance to change. By measuring the variation with the eddy current testing instrument, the defect on the metal surface or other changes in physical properties can be identified.

There are many factors affecting the eddy current field, such as the coupling degree between the probe coil and the tested material, the shape and size of the material, conductivity, permeability, and defects, etc. Therefore, the eddy current principle can be used to solve the problems of metal material flaw detection, thickness measurement and sorting.

We did eddy current vs ultrasonic testing,eddy current testing and we mastered ultrasonic flaw detector theory,ultrasonic flaw detector working principle and pulsed eddy current principle,so our products like ndt machine,which can be guaranteed.

The basic working principle of eddy current testing instrument is as follows:

When the test coil with alternating current is close to the conductor workpiece, the alternating magnetic field generated by the coil will cause the conductor to generate current (eddy current). The size, phase and flow pattern of eddy current are affected by workpiece properties (conductivity, permeability, shape, size) and defects. The voltage and impedance of coil are changed by the reaction of magnetic field.

Therefore, the change of voltage or impedance of the test coil can be measured by the instrument, and the nature, state and defect of the workpiece can be judged.

Characteristics of Eddy Current Testing Instrument

1. Scope of application of eddy current testing instruments

(a) Process inspection and final product inspection: quality control during manufacturing process or rejection of non-conforming products in finished products.

1. b) In-service inspection: periodic inspection for mechanical parts and heat exchange pipes and other facilities.

1. c) Other applications: thickness measurement of metal sheets and coatings, material sorting, conductivity measurement, etc.

2. Advantages of Eddy Current Testing Instruments

(a) No contact with the workpiece and no coupling agent are needed in the detection, which can be carried out at high temperature. At the same time, the probe can be extended to remote detection, which can effectively detect the narrow area and deep hole wall of the workpiece.

1. b) The detection sensitivity of surface and near surface defects is very high.

1. c) It is easy to realize high-speed and high-efficiency automatic detection for the detection of tubes, rods and wires. It can digitally process the test results, and then store, reproduce and process the data.

BKN is one of the professional ndt equipment manufacturers,we master the eddy current testing principle,we also produce ndt testing machine,we will be your best partner.

Pulsed eddy current inspection technology is a new non-destructive testing technology for subsurface defect detection. It is a new application field of eddy current testing. It determines the location of defect by the time when the maximum magnetic field appears, so as to realize non-destructive detection and quantitative description of defect.

As early as the 1970s, Libby of the United States put forward the theory and application of pulsed eddy current inspection technology. However, in recent years, this technology has made some substantial progress and success in the University of Iowa in the United States, DERA in the United Kingdom and Cegely Laboratory in France, and has attracted much attention in the research and development of modern non-destructive testing technology. Compared with the traditional single-frequency sinusoidal eddy current, the pulsed eddy current has many advantages.

Traditional eddy current uses sinusoidal current of a single frequency as excitation, while square wave with a certain duty cycle is used as excitation in pulsed eddy current inspection. The traditional pulsed eddy current inspection is used to analyze the steady state of the induced magnetic field, that is, to determine the position of the defect by measuring the amplitude and phase angle of the induced voltage, while the pulse eddy current is used to analyze the transient state of the induced magnetic field in time domain to detect the defect by the time when the maximum value of the induced magnetic field appears directly. In theory, pulsed eddy current can provide more information than single-frequency sinusoidal eddy current, because pulsed eddy current can provide a range of continuous multi-frequency excitation.

In addition, the pulsed eddy current inspection signal responds faster than the multi-frequency eddy current signal because it runs a different current frequency at the same time.

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The basic principle of the eddy current apparatus is to place the coil with alternating current on the metal plate to be measured or outside the metal tube to be measured. At this time, the alternating magnetic field will be generated in the coil and its vicinity, so that the induced alternating current in the sample will be whirlpool, which is called eddy current. The distribution and size of eddy current depends not only on the shape and size of the coil, the size and frequency of AC current, but also on the conductivity, permeability, shape and size of the specimen, the distance from the coil and the presence or absence of cracks on the surface. Therefore, under the condition of keeping other factors relatively unchanged, the change of magnetic field caused by eddy current can be measured by a detection coil. The size and phase change of eddy current in the specimen can be inferred, and then the information about the change of conductivity, defects, material condition and other physical quantities (such as shape, size, etc.) or the existence of defects can be obtained. However, because the eddy current is an alternating current and has skin effect, the detected information can only reflect the situation on or near the surface of the specimen.

The application of eddy current apparatus: According to the shape of the sample and the purpose of testing, different coils can be used, usually three types: through coil, probe coil and insertion coil. The through coil is used to detect pipes, bars and wires. Its inner diameter is slightly larger than that of the tested object. When the tested object passes through the coil at a certain speed, cracks, inclusions, pits and other defects can be found. Probe coil is suitable for local detection of specimens. When applied, the coil is placed on the metal plate, tube or other parts, which can check the fatigue cracks on the inner barrel of the airplane landing pole and turbine engine blade, etc. Inserted coils, also known as internal probes, are placed in the holes of pipes or parts for inner wall detection, and can be used to check the corrosion degree of the inner walls of various pipes. In order to improve the detection sensitivity, the probe coil and the insertion coil are mostly equipped with magnetic cores. The eddy current method is mainly used for the rapid detection of metal pipes, rods and wires on production lines and for the detection of large quantities of parts such as bearing steel balls and valves (besides eddy current instruments, mechanical devices for automatic loading and unloading and transmission), material sorting and hardness measurement, as well as for the thickness measurement of coatings and coatings.

Advantages of eddy current apparatus: When eddy current is detected, the coil does not need to be directly contacted with the measured object. It can carry out high-speed detection and it is easy to realize automation.

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Are you looking for  eddy current equipment for sale?

ECT Eddy current testing is a non-contact testing method, which mainly uses the electromagnetic field and electromagnetic induction between metals to detect. It is one of the NDT non-destructive testing methods in the industry.

We can use different coils according to the shape of the specimen and the purpose of detection. There are usually three types of coils: through a coil, probe coil and insert coil. It is mainly used for the rapid detection of metal pipes, rods and wires on production lines, and for the detection of large quantities of parts such as bearing steel balls, valves, etc.

The main features of eddy current tester are:

1) The detection sensitivity of the surface of the conductive material and the near surface defects is high;

2) A wide range of applications can be monitored for various physical and technological factors affecting the characteristics of induced eddy currents;

3) It is easy to realize high-speed, high-efficiency and automatic detection of tubes, rods and wires without using a coupling agent;

4) Under certain conditions, it can reflect information about the crack depth;

5) Monitoring can be carried out in the case where other detection methods such as high temperature, thin-walled tubes, thin wires, and inner surface of the parts are not applicable.

Eddy current testing equipment for tube, bar and wire including BKNET-999/H Copper Tube Eddy Current Flaw Detector, GSET-551steel wire eddy current testing, BKNET-101 Automatic Eddy Current Flaw Detector, Rod Tube Rotary Eddy Current Flaw Detector ET-R-15/40/65/90, BKNET-01\02 Welded Pipe Eddy Current Flaw Detector, LGET-553 Aluminum Tube Eddy Current Flaw Detector.

These equipments are mainly applicable to the surface defect detection of ferromagnetic non-ferrous metals, austenite, stainless steel tubes, rods and discs. It can be widely used for on-line or off-line  NDT non-destructive testing of raw materials in energy, petrochemical, bearing, automobile, transom manufacturing, household appliances and other industries, such as bearings, raw materials of high strength bolts, copper, aluminum tubes of various refrigeration equipment, condenser tubes of evaporators, etc. This system is the necessary testing equipment for pipe and bar and wire production and application factory. This system adopts rotating balance point probe, resolver signal coupling, synchronously adjusting double detection probe, and the detection method of workpiece passing straight line. It has the characteristics of stable and reliable performance, high detection sensitivity, fast detection speed, no need for magnetizing and demagnetizing devices, and is sensitive to defect detection of pipe, bar and wire. It can make 100% NDT non-destructive detection of raw material surface. The equipment has the functions of defect alarm, automatic feeding and unloading and automatic sorting to achieve the detection automation. It provides an effective detection means for mass production of application pipes, rods and wires in factories and enterprises to ensure quality.

Nanjing BOKENA Automation System Co., Ltd., originated from the eddy current testing laboratory of the Nanjing University of Technology. It is one of the most professional ndt testing equipment suppliers in China. We sincerely invite and welcome people from all around the world to invest and create more values together.

Bolt: Mechanical parts, cylindrical threaded fasteners with nuts. A type of fastener consisting of a head and a screw (a cylinder with an external thread) is required to be fitted with a nut for fastening the two parts with through holes. This type of connection is called a bolted connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

BKNFX-11 bolt eddy current sorter is suitable for high-strength bolt heat treatment state, crack, wrong thread anchor, and mixture sorting.

The shape of bolt:

Generally, the countersunk head is used where the surface is smooth and does not protrude after the connection is required because the countersunk head can be screwed into the part. The round head can also be screwed into the part. The tightening force of the square head can be larger, but the size is large. In addition, in order to meet the needs of locking after installation, there are holes in the head and holes in the rods, which can not loosen the bolt when it is vibrated. Some bolts without threads are to be thin, called thin waist bolts. This type of bolt facilitates the coupling of the force. There are special high-strength bolts on the steel structure, the head will be larger and the size will change.

In addition, there are special uses: T-slot bolts, the most used on machine tool fixtures, special shape, cut off both sides of the head. Anchor bolts for machine and floor attachments are available in a wide variety of shapes. U-bolts, as mentioned above. and many more. There is also a special stud for welding. One end has a thread and one end is not welded. It can be welded to the part and the other side can be directly screwed.

Bolt Vortex Sort BKNFX-11 Brief

1. Non-destructive testing, no special requirements for workpiece surface. (Avoiding the defect that the traditional detection method needs to destroy the surface state of the workpiece, and only two standard samples are prepared in the same material and workpiece when debugging the instrument.)

2. Fast, accurate and convenient. (The test only needs to put the workpiece into the probe, the efficiency is several times or even hundreds of times of the traditional detection method. For the qualified parts and the unqualified with the sound and light alarm function).

3. High sensitivity. (The voltage and frequency used by different materials and heat-treated parts are continuously adjustable)

4. Simple operation. (The man-machine dialogue function is set inside the instrument)

5. Visual display. The software compiled by the WINDOWS operation platform makes the instrument more convenient and intelligent.

6. Suitable for large-scale testing needs, to ensure product quality. (100% of the raw materials and finished products can be tested, instead of the conventional sampling test)

Sorting accuracy

1. Rockwell hardness (+2HRC)     

2. 100% sorting of material mixtures

3. Crack length * width * depth (5 * 0.05 * 1mm)

Nanjing BOKENA Automation System Co., Ltd., originated from the eddy current testing laboratory of the Nanjing University of Technology. It is one of the most professional ndt testing equipment suppliers in China. We sincerely invite and welcome people from all around the world to invest and create more values together.

Eddy current testing of welds is the use of eddy current technology to test the welded pipe, this type of testing is based on the premise of lossless. At the same time, we need to be clear that the welded pipe is, in general, the steel pipe that we usually say, which is a welded steel pipe.

Eddy current weld testing is a non-destructive testing technique for detecting component defects by using the principle that the eddy current induced by the AC electromagnetic coil on the surface of the metal member encounters a defect. The oscillating current is generated in the conductive member by the excitation coil by the principle of electromagnetic induction, and the amount of change in the eddy current is measured by the detecting coil, thereby obtaining information on the component defect.

Eddy current testing is a non-destructive testing technique in which an alternating current electromagnetic coil induces eddy currents on the surface of a metal member. It is suitable for the detection of defects in conductive materials, including ferromagnetic and non-ferromagnetic metal materials.

BKNET-01\02 NDT weld testing equipment is used for on-line and off-line inspection of welded pipes. It has high sensitively to axial defects such as unwelded welding, dark spots and open cracks. In the production process, products are caused by welder failure. Slow and long-term injuries can be reliably detected.

BKNET-0102 Welded Pipe Eddy Current Flaw Detector performance 

BKNET-0102 Welded Pipe Eddy Current Flaw Detector Features:

High precision end and end-to-tail signal removal

High precision real-time, delayed alarm output

Fast digital／analog electronic balance

Memory track delay blanking function  

Non-equal amplitude phase／amplitude alarm domain

Remote automatic help system

Synchronous alarm output for internal and external clock control

Nanjing BOKENA Automation System Co., Ltd., originated from the eddy current testing laboratory of the Nanjing University of Technology. It is one of the most professional ndt testing equipment suppliers in China. We sincerely invite and welcome people from all around the world to invest and create more values together.

Magnetic flux leakage test refers to the formation of a leakage magnetic field on the surface of a test piece after it is magnetized due to defects on the surface or near-surface of the test piece. People can detect defects by detecting changes in the leakage magnetic field.

Briefly describe the magnetization of ferromagnetic components. In the magnetic non-destructive testing, magnetization is the first step to realize the detection, which determines whether the leakage magnetic field signal can be generated, and also affects the performance characteristics of the detection signal and the structural characteristics of the detection device.  Like magnetic particle inspection, magnetization is achieved by a magnetizer, including both a magnetic source and a magnetic circuit.  The magnetic source and the magnetic circuit change depending on the structure of the member to be tested.

What kind of magnetization can be divided into several categories? The magnetization methods can be generally divided into five categories, namely, alternating current magnetization mode, direct current magnetization mode, permanent magnet magnetization mode, composite magnetization mode, and integrated magnetization method.

What are the characteristics of magnetic flux leakage detection technology?

Because leakage magnetic field detection uses magnetic sensors to detect defects, compared with magnetic powder, penetration and other methods, it has the following advantages:

1. It is easy to realize automation. The computer judges the presence or absence of defects based on the detected signals. 
2. The fundamentally high detection reliability can solve the influence of human factors in the magnetic powder and osmosis method, and has high detection reliability.  
3. can achieve preliminary quantification of defects.  In the range of wall thicknesses up to 30 mm, the inner and outer wall defects can be detected simultaneously.  In the detection of the pipeline, 5 high-efficiency, pollution-free automated inspection can achieve high detection efficiency.

BKN's portable mfl equipment are capable of detecting workpieces efficiently and accurately. 

As one of the most professional ndt testing equipment suppliers  in China, we offer mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

Technical Characteristics of MFL101 Tank Floor MFL Scanner

Unique full modular structure, from the main body of the computer mechanism the handle of MFL101 Tank Floor MFL Scanner can be quickly folded, disassembled. It is easy to transport and access manholes. With humanized operation design, the height of armrest and adjustable angle, suitable for different operators. Precise signal conditioning circuit. The four-layer PCB with mixed power excellent performance. data word signal processing system, supercomputing power, advanced evaluation algorithm.

High-performance touch industrial tablet. The operation is very convenient does not require a keyboard and mouse. Unique probe design. It can pick up the magnetic flux leakage signal to overcome the unwanted signal caused by the eddy current effect. The number of physical channels is up to 32. High-performance lithium battery pack, which is at least 50% lighter than the equivalent capacity lead-acid battery Software design that can be operated efficiently. 

All scan parameter settings graphical, intuitive, and easy to use, dramatically increasing the speed of operation and avoiding errors. The magnetization is quickly adjustable. By adjusting the ground clearance the magnetic pole, the magnetization of the detection target plate can be quickly changed to meet the requirements of detecting the thickness and minimize the gravity of the instrument and the bottom plate. This design allows the instrument to adapt to a wide range of floor thicknesses and reduce operator effort, increasing battery life. 

Different degrees of corrosion are represented by non-color blocks. Online analysis of corrosion degree and position, position coordinates can be displayed in a table or on a scan.

MFL101 Tank Floor Scanner Performance Parameters Host:

Industrial tablet computer interface: 
Chinese Working principle: Magnetic flux leakage method: 
NdFeB permanent magnet Channel number: 32
Scan width: 260mm 
Drive mode: DC brushless motor, worm gear reducer, The motor can be raised. 
Convert manual and electric drives at any time. 

Detection speed: 0 m / s~0.7m /s step-less adjustable 
Detection thickness: 8-20mm Penetration coating: non-magnetic 
Penetration thickness: <4mm 
Sensitivity: can be set (8-12mm thick 20 % material loss of the bottom plate, 40% material loss of the 12-20mm thick bottom plate 
Data storage: local hard disk storage, USB disk dumping 
Real-time analysis: Yes 
Offline software
Battery specification: 14V40AH

As one of the most professional non destructive testing equipment manufacturers in China, we offer mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

Electromagnetic detection is a very important non-destructive testing method and is widely used. Magnetic flux leakage is a magnetic method of nondestructive testing that is used to detect corrosion and pitting in steel structures, most commonly pipelines and storage tanks. The basic principle is that a powerful magnet is used to magnetize the steel. When used in combination with other methods, it provides a quick and inexpensive assessment of the workpiece of ferromagnetic materials. With the advancement of technology, people are paying more and more attention to the automation of the inspection process. This not only reduces the labor intensity of the inspection work but also improves the reliability of the test results and reduces the influence of human factors. The MFI magnetic flux leakage inspection method is a highly automated magnetic detection technology. The principle is that after the ferromagnetic material is magnetized, the surface and near-surface defects form a leakage magnetic field on the surface of the material, and defects are detected by detecting the leakage magnetic field. In this sense, the magnetic particle detection technology commonly used in pressure vessel inspection. However, it is customary to use the method of measuring the leakage flux with a sensor as the magnetic flux leakage detection, and the magnetic flux to detect the leakage flux. The method is called magnetic particle detection and they are juxtaposed into two detection methods.

Portable Magnetic Flux Leakage Testing Equipment

Magnetic flux leakage test refers to the formation of a leakage magnetic field on the surface of a test piece after it is magnetized due to defects on the surface or near surface of the test piece.

Benchtop Magnetic Flux Leakage Testing Equipment

Magnetic flux leakage testing procedure refers to the formation of a leakage magnetic field on the surface of a test piece after it is magnetized due to defects on the surface or near surface of the test piece.

Magnetic particle testing can only detect surface and near-surface crack defects, and it needs surface grinding when testing. It is only suitable for the detection of workpiece discontinuation. In addition to the surface and near-surface crack defects, the MFI magnetic flux leakage inspection can also find the corrosion inside the workpiece from the outside. Defects such as pits, and do not need to be polished on the surface of the workpiece, suitable for on-line inspection of workpieces. On-line inspection of workpieces is currently the most urgent method for users, which can reduce unnecessary parking and reduce inspection costs. In addition, the magnetic flux leakage equipment  can also quantify the depth and length of defects. Although the application of magnetic flux leakage detection technology is rarely used in workpiece inspection, it has the advantages that magnetic particle detection does not have, so its application prospect is very broad.

As one of the most professional  non destructive testing equipment manufacturers in China, we offer mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

Automatic EDM Notch is a kind of EDM notch machine, and it is the ideal equipment for processing artificial defects of pipe rod standards in non-destructive testing work. The flaw detector has the characteristics of simple operation, safety and reliability, high production precision, fast processing speed, and convenient carrying by ultrasonic flaw detection. It can process artificial defects on non-ferrous metals and ferrous metal tubes and bar standards. Hardness sorting can process longitudinal, transverse, and oblique rectangular groove injuries on the inner and outer surfaces of the tube and rod. The core part of the equipment adopts advanced digital processing technology and system integration technology. With modern advanced digital control and servo technology, the injury process is fully automated, with high processing precision, fast speed, easy operation and performance at the international advanced level. The entire instrument is portable and easy to carry and has low requirements for the environment of steel pipe scratching.

How electronic fence works

After the pulse generator (main unit) is energized, the transmitting port sends a pulse voltage to the front fence. The time interval is about 1.5 seconds, and the pulse stays on the fence for about 0.1 second. After the loop is formed on the front fence, the pulse is returned to the host for reception. Port, this port receives the feedback pulse signal; the host also detects the resistance between the two transmitters. If the front fence is broken and the circuit is broken or shorted, the receiving port of the pulse host can not receive the pulse signal or the resistance between the two transmitters is too small, the host will issue an alarm.

Fence alarm

Through the working principle of the electronic fence, no matter what voltage working state the pulse host is in, when the fence is damaged, the receiving port can not receive the pulse signal, the pulse host will alarm; similarly, when the two electronic cables are short-circuited When the resistance is very small, the pulse master will also alarm.

As one of the most professional non destructive testing equipment manufacturers in China, we offer mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

An electric pulse is a pulse generated by electrons, and a pulse is a process of changing a voltage in a short time. Electropulsing is an unsteady current field generated by a capacitor or an intermittent source. The alternating current we use can be regarded as a pulse current, and one of the cycle processes can be regarded as an electrical pulse. Modern electric pulse technology has developed to the trend of higher frequency and high energy peaks. It has a wide range of applications in materials testing, biology, medicine, nuclear energy, military and other fields. The main working principles are high energy Joule heating effect, hot pressing effect, high-frequency magnetic induction effect, electroforming and so on. Common waveforms are a rectangular, sinusoidal, rectangular, sinusoidal, group, and so on.

The EDM notch is mainly used for the production of standard sample tubes in the non-destructive testing industry, and is an indispensable auxiliary device for nondestructive testing. It can be used to make internal and external longitudinal defects on the sample tube, internal and external lateral defects, and can also make oblique defects at a certain angle according to different requirements of users, and can also make thickness measurement standard sample tubes or layered standard sample tubes. The shape has a U-shaped groove, a rectangular or square groove, a flat bottom hole, and the like. The machining precision is high, the speed is fast, the operation is simple, the degree of automation is high, and the machining depth can be set in one time, and the error is within the allowable tolerance range. The device is light and easy to carry, and can be used in different field environments.

The main features of the EDM Notch:

Small size, light weight and easy to carry

High power, fast scratching, less than 10% error

The distance between the internal injury position and the tube end is not limited, and the position of the wound is accurate

Single-chip control, simple operation, intelligent and efficient, practical

It is only necessary to clean the circulating oil normally, and it is basically maintenance-free

You can get the perfect EDM notching services if you contact us.

As one of the most professional non destructive testing equipment manufacturers in China, we offer  mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

Bokena has eddy current machine for sale!

GTET-02 Cylinder Liner Eddy Current Testing Machine Introduction

1. Test object: inner diameter and an outer diameter of the cylinder liner 
2. Standard defective parts: a flat bottom hole with a depth of 0.5 mm and a diameter of 0.5 mm extending from the surface of the workpiece to the metal. 
3. The rate of missed standard defect is 0%; the rate of false positives (only misidentified products are judged as non-conforming products) ≤1%.

Detection method

Eddy current testing is to connect the conductor to the coil with alternating current. The alternating magnetic field is established by the coil. The alternating magnetic field passes through the conductor and electromagnetic induction is applied to establish an eddy current in the conductor. 

The eddy currents in the conductor also generate their own magnetic field, and the action of the eddy current magnetic field changes the strength of the original magnetic field, which in turn causes a change in the coil voltage and impedance.

When a defect occurs on the surface or near-surface of the conductor, the intensity and distribution of the eddy current will be affected. The change of the eddy current causes a change in the voltage and impedance of the detecting coil. According to this change, the existence of the defect in the conductor can be indirectly known.

Since the shape of the test piece is different and the detection position is different, the shape of the test coil is different from that of the test piece. In order to meet various testing needs, various detection coils and eddy current testing instruments have been designed.

1. detection coil and its classification

In eddy current testing, the detection coil is used to establish an alternating magnetic field; the energy is transmitted to the conductor to be inspected, and the alternating magnetic field established by the eddy current is used to obtain the quality information in the detected conductor. Therefore, the detection coil is a transducer.

The shape, size and technical parameters of the test coil are critical to the final inspection. In eddy current testing, the type of detection coil is often selected according to the shape, size, material, and quality requirements (testing standards) to be detected. There are three types of commonly used detection coils.

1) Through coil

The through the coil is a coil that detects the sample to be tested and put it in the coil and is suitable for flaw detection of tubes, rods, and wires. Since the magnetic field generated by the coil acts first on the outer wall of the sample, the effect of detecting the outer wall defect is good, and the detection of the inner wall defect is performed by the penetration. In general, the detection sensitivity of the inner wall defect is lower than that of the outer wall. The drawback of thick-walled tubing is that it cannot be detected using an externally wound coil.

2) Interpolated coil

The interposer coil is a coil placed inside the tube for inspection. It is used to inspect the defects of thick walls or the inner walls of the borehole. It is also used to check the quality of the tubes in the complete equipment, such as the in-service inspection of heat exchanger tubes.

3) Probe coil

The probe coil is a coil placed on the surface of the sample for inspection. It is not only suitable for surface scanning inspection of simple plates, slabs, billets, round billets, bars and large diameter pipes, but also for complex shapes. Inspection of mechanical parts. Compared with the through the coil, the probe coil is suitable for detecting small surface defects due to its small volume and small field action range.

As one of the most professional non destructive testing equipment manufacturers in China, we offer mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

GSET-551 Steel Wire Eddy Current Flaw Detector Brief 

Using the eddy current signal processing method and high-performance DSP algorithm, the NDT wire rope tester detection ability of micro-crack is as high as 0.05mm deep crack.

Using computer digital technology and "digital eddy current detection technology" to achieve high-speed data processing capabilities, detection speed can be reached to 1~500m/min.  Technology can effectively suppress all kinds of interference signals. It has waveform, amplitude, phase, X-axis and Y-axis signals.

The professional "digital filtering" is adopted to effectively suppress the interference signal in the field and ensure the accuracy and stability of the detection.

Features of GSET-551 Steel Wire Eddy Current Flaw Detector

1. LF testing sensitivity

The detector detects the minimum metal cross-sectional area change and the minimum length of the damage length corresponding to the local damage.

2.  LMA testing sensitivity

The detector detects the minimum metal cross-sectional area change and the damage length minimum size corresponding to the metal cross-sectional area loss.

3.  LMA repeatability error

The maximum value of the random error obtained by performing multiple consecutive measurements of the same metal cross-sectional area change in the same test sample under the same test environment and conditions within the instrument range.

4.  LMA linearity error

Within the range of the instrument, the metal cross-sectional area of the test sample is linearly proportional to the absolute value of the maximum deviation between the measured curve of the instrument and the calibration curve fitted by the measured value of the cross-sectional area of the metal.

5.  LMA error of indication

The value of the metal cross-sectional area loss measured by the instrument minus the actual value of the metal cross-sectional area loss within the instrument's range.

6.  LMA linearity error

In the range of the instrument range, under the condition of the length loss of the cross-sectional area of the metal, the cross-sectional area loss of the metal on the wire rope measured by the detector is matched with the value of the loss of the cross-sectional area of a group of wire ropes measured by the instrument. The absolute value of the maximum deviation between the calibration curves.

7. Testing distance resolution

The detector is capable of detecting the resolved minimum distance.

8. Dual function instrument

The detector can detect and display changes in metal cross-sectional area loss (LMA) on one channel, and detect and display local damage (LF) on the other channel. The detector recording device can be a computer, graphic recorder or other matches. device.

9. Single-function instrument

The detector cannot simultaneously detect and display metal cross-sectional area loss changes and local damage, and can only detect and display one of them. The detector recording signal device can be a computer, a graphic recorder or other matching devices.

10. Wire rope electromagnetic tester

The detector principle and composition meet the requirements of the GB/T 21837-2008 standard, and it has a detector for detecting distance display, data storage or recording function.

As one of the most professional  non destructive testing equipment manufacturers in China, we offer ndt machine. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

The connecting rod hardness eddy current sorting machine has a calibration device, input compensation parameters, automatic/manual temperature compensation and light intensity compensation, and automatic temperature measurement and temperature correction. The digital potentiometer is used to adjust the gain of the amplifier through program control. The gain parameters can be set for different battery chips, and the software working mode can be changed to adapt to various battery test applications without changing the hardware.

Features of the connecting rod hardness sorter:

1. The sorting instrument is divided into eddy current hardness testing(can display Brinell, Rockwell hardness), flaw detection and so on. 
2. Hardness test: After starting the machine, use the hardness test probe to perform hardness test sorting on the workpiece. The Brinell or Rockwell value can be selected. The liquid crystal display will show the hardness value of the workpiece.
3. Detection of flaw detection: The workpiece to be tested shall be of the same specification. The instrument shall be calibrated with standard parts (work without damage), and the flaw detection curve on the display shall be adjusted to the upper limit and the intermediate standard point of the lower line. After calibration, Sort the workpiece for sorting.

Connecting rod hardness vortex sorting machine LGYDFX-01 Performance

As a non-destructive testing instrument and equipment, sensor development company, BKN Technology has been an innovative manufacturer of high-quality, high-performance non-destructive testing instruments and equipment. We provide customer-centric design services to meet the different application needs of our users.

As one of the most professional ndt testing equipment suppliers  in China, we offer ndt machine. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

Bolt: Mechanical parts, cylindrical threaded fasteners with nuts. A type of fastener consisting of a head and a screw (a cylinder with an external thread) is required to be fitted with a nut for fastening the two parts with through holes. This type of connection is called a bolted connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

BKNFX-11 bolt eddy current sorter is suitable for high-strength bolt heat treatment state, crack, wrong thread anchor, and mixture sorting.

The shape of bolt:

Generally, the countersunk head is used where the surface is smooth and does not protrude after the connection is required because the countersunk head can be screwed into the part. The round head can also be screwed into the part. The tightening force of the square head can be larger, but the size is large. In addition, in order to meet the needs of locking after installation, there are holes in the head and holes in the rods, which can not loosen the bolt when it is vibrated. Some bolts without threads are to be thin, called thin waist bolts. This type of bolt facilitates the coupling of the force. There are special high-strength bolts on the steel structure, the head will be larger and the size will change. 

In addition, there are special uses: T-slot bolts, the most used on machine tool fixtures, special shape, cut off both sides of the head. Anchor bolts for machine and floor attachments are available in a wide variety of shapes. U-bolts, as mentioned above. and many more. There is also a special stud for welding. One end has a thread and one end is not welded. It can be welded to the part and the other side can be directly screwed.

Bolt Vortex Sort BKNFX-11 Brief

1. Non-destructive testing, no special requirements for workpiece surface. (Avoiding the defect that the traditional detection method needs to destroy the surface state of the workpiece, and only two standard samples are prepared in the same material and workpiece when debugging the instrument.)
2. Fast, accurate and convenient. (The test only needs to put the workpiece into the probe, the efficiency is several times or even hundreds of times of the traditional detection method. For the qualified parts and the unqualified with the sound and light alarm function).
3. High sensitivity. (The voltage and frequency used by different materials and heat-treated parts are continuously adjustable)
4. Simple operation. (The man-machine dialogue function is set inside the instrument)
5. Visual display. The software compiled by the WINDOWS operation platform makes the instrument more convenient and intelligent.
6. Suitable for large-scale testing needs, to ensure product quality. (100% of the raw materials and finished products can be tested, instead of the conventional sampling test)

Sorting accuracy

1. Rockwell hardness (+2HRC)     
2. 100% sorting of material mixtures
3. Crack length * width * depth (5 * 0.05 * 1mm)

As one of the most professional ndt testing equipment suppliers  in China, we offer  mfl ndt. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.

Eddy current testing of welds is the use of eddy current technology to test the welded pipe, this type of testing is based on the premise of lossless. At the same time, we need to be clear that the welded pipe is, in general, the steel pipe that we usually say, which is a welded steel pipe.

Eddy current weld testing is a non-destructive testing technique for detecting component defects by using the principle that the eddy current induced by the AC electromagnetic coil on the surface of the metal member encounters a defect. The oscillating current is generated in the conductive member by the excitation coil by the principle of electromagnetic induction, and the amount of change in the eddy current is measured by the detecting coil, thereby obtaining information on the component defect.

Eddy current testing is a non-destructive testing technique in which an alternating current electromagnetic coil induces eddy currents on the surface of a metal member. It is suitable for the detection of defects in conductive materials, including ferromagnetic and non-ferromagnetic metal materials.

BKNET-01\02 NDT weld testing equipment is used for on-line and off-line inspection of welded pipes. It has high sensitively to axial defects such as unwelded welding, dark spots and open cracks. In the production process, products are caused by welder failure. Slow and long-term injuries can be reliably detected.

BKNET-0102 Welded Pipe Eddy Current Flaw Detector performance 

BKNET-0102 Welded Pipe Eddy Current Flaw Detector Features:

High precision end and end-to-tail signal removal 

High precision real-time, delayed alarm output

Fast digital／analog electronic balance

Memory track delay blanking function  

Non-equal amplitude phase／amplitude alarm domain 

Remote automatic help system

Synchronous alarm output for internal and external clock control 

As one of the most professional non destructive testing equipment manufacturers in China, we offer ndt machine. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future. 

Bokena is one of the most professional eddy current test equipment suppliers in China. We have been devoted to produce ect testing equipment and ect ndt for many years.

ECT Eddy current testing is a non-contact testing method, which mainly uses the electromagnetic field and electromagnetic induction between metals to detect. It is one of the NDT non-destructive testing methods in the industry.

The principle of eddy current testing is that the coil with alternating current is placed on the metal plate to be measured or outside the metal, tube to be measured (see figure). The alternating magnetic field will be generated inside and near the coil, which makes the induced alternating current in the sample appear to be eddy, which is called eddy current. Under certain conditions, the current through the coil is invariable. If the coil is close to the workpiece under test, like a ship in the water, the eddy current will be induced in the workpiece. Under the influence of the eddy current, the coil current will change. Because the size of the eddy current varies with the defect in the workpiece, the change of coil current can reflect the defect in the workpiece.

Eddy Current Testing Equipment for Tube, Bar and Wire

Eddy current testing is a non-contact testing method, which mainly uses electromagnetic field and electromagnetic induction between metals to detect. It is one of the non-destructive testing methods

ECT For Automotive And Aerosapce

Eddy current testing technology has been widely used in the detection of metal components in the aerospace and aerospace fields. In order to ensure the flight safety of the aircraft, the relevant

Eddy current testing equipments are our flagship products, it contains eddy current testing equipment for tube, bar and wire & eddy current testing equipment for automotive parts and aerospace. Eddy current testing equipment for tube, bar and wire including BKNET-999/H Copper Tube Eddy Current Flaw Detector, GSET-551steel wire eddy current testing, BKNET-101 Automatic Eddy Current Flaw Detector, Rod Tube Rotary Eddy Current Flaw Detector ET-R-15/40/65/90, BKNET-01\02 Welded Pipe Eddy Current Flaw Detector, LGET-553 Aluminum Tube Eddy Current Flaw Detector.

Eddy current testing equipment for automotive parts and aerospace including BKNFX Pre-Multi-Frequency Eddy Current Hardness Separator, BKNET Series Multi-frequency and Multi-filter Eddy Current Flaw Detector, ET-F1 Engine Cylinder Bore Eddy Current Flaw Detector, GTET-02 Cylinder Liner Eddy Current Flaw Testing Machine, Steel Ball Hardness eddy current separator GQYDFX-01, GZET-01 Roller Automatic Eddy Current Flaw Testing Machine, Roller Hardness eddy current Separator GZYDFX-01, Piston Rod Eddy Current Flaw Detector HSGET-04, HSXET-02 Piston Pin Eddy Current Tester, Precision Axis Eddy Current Flaw Detector JMZET-04, Connecting Rod Hardness eddy current Sorting Machine LGYDFX-01, Hub Bearing Eddy Current Flaw Detector LGTSET-A/B, Bolt Vortex Sorter BKNFX-11, Flame Quenching Valve Rod End Hardness Eddy Current Sorter QMYDFX-01, QTXET-01 Ball Socket Eddy Current Sorter, QTXFX-01Ball Socket Hardness Eddy Current Sorter, SCPET-04 Brake Disc Eddy Current Flaw Detector, TLET-04 Camshaft Eddy Current Flaw Detector, TLZET-99 Camshaft Eddy Current Flaw Detector, Tapered Roller Online Eddy Current Flaw Detector YZGZET-01, Ring Crack and Hardness Combination Flaw Detector TQJC-02.

As one of the most professional ndt testing equipment suppliers in China, we offer ndt machine. We welcome merchants from all over the world to cooperate with our factory for mutual benefit and win-win, and jointly create a better future.