Our company's fully automatic inner and outer ring combination machine consists of an eddy current testing section and a hardness testing section; Our company can also equip customers with corresponding loading and unloading devices according to their production needs.
·Technical parameters and performance indicators
Hardness material sorting section:
1. Automatic sorting (removal), automatic material layout, automatic statistics of the total number of inspected workpieces, qualified number, qualified rate, and other functions
2. After inspection, there is no damage to the parts
3. No auxiliary processes such as demagnetization and cleaning are required after inspection
4. Error range: Hardness testing sensitivity: Rockwell: ± 2HRC; Vickers: ± 40Hv
5. Type of probe: Through type probe
6. Characteristics of hardness material sorting instrument
1) Probe excitation current: adjustable from 1 to 256 levels
2) Linear gain: 1-256 times
3) Provide eight frequency measurement signal amplitude displays and sort them according to the set threshold value
4) Analog and digital fast automatic zero adjustment
5) Impedance plot points display phase and amplitude changes
6) Automatic measurement and display of X/Y component values and amplitude values
7) Elliptical sorting domain can be automatically set based on sampling points, and its position and size can be manually adjusted
8) Can be used for manual and online automatic detection, with adjustable signal delay and detection time
9) Provide sorting control signals
Eddy current testing section:
1. Sensitivity of flaw detection: cracks and defects that extend from the surface of the workpiece to the inside of the metal with a depth of ≥ 0.05mm and a length of ≥ 1mm; For cracks inside the metal that have not yet extended to the surface of the workpiece, cracks with a depth of ≥ 0.2mm and a length of ≥ 1mm can be detected when the metal thickness between the upper edge of the crack and the surface of the workpiece is ≤ 0.2mm
2. Characteristics of eddy current testing instruments:
1) Detection frequency range: 100Hz~1MHz, adjustable
2) Band pass filtering, center frequency 250-1000KHz, 8 levels
3) Gain: Each channel has a gain of 0-60dB, with an adjustment of 1dB per level
4) Phase: 0 °~360 °, with a step distance of 1 °
Principle of eddy current testing:
Eddy current detection is the application of electromagnetic induction principle, which excites the probe coil with a sine wave 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 direction of induced current is a concentric circular coil, resembling a vortex, called an eddy current. At the same time, eddy currents also generate a magnetic field of the same frequency, which is opposite to the direction of the coil magnetic field. The loss resistance of the eddy current channel, as well as the anti magnetic flux generated by the eddy current, are reflected back to the probe coil, changing the current magnitude and phase of the coil, that is, changing the impedance of the coil. Therefore, when the probe moves on the metal surface and encounters defects or changes in material, size, etc., the reaction of the eddy current magnetic field on the coil is different, causing changes in the coil impedance. By measuring this change with an eddy current detection instrument, the presence of defects or other physical and material changes on the metal surface can be identified. There are many factors that affect the eddy current field, such as the degree of coupling between the probe coil and the tested material, the shape and size of the material, conductivity, permeability, and defects. Therefore, the principle of eddy current can be used to solve problems such as metal material inspection, thickness measurement, and sorting
Technical parameters:
Sensitivity of flaw detection: cracks and defects that extend from the surface of the workpiece to the inside of the metal with a depth of ≥ 0.05 mm and a length of ≥ 2 mm; For cracks inside the metal that have not yet extended to the surface of the workpiece, cracks with a depth of ≥ 0.20mm and a length of ≥ 1mm can be detected when the metal thickness between the upper edge of the crack and the surface of the workpiece is ≤ 0.2 mm.
There are two methods to eliminate the harm of magnetic permeability of ferromagnetic materials and metal materials to non-destructive testing:
Firstly, select far-field eddy current testing methods;
Secondly, conduct saturation magnetization on the steel pipe before conducting inspection.
The former method requires upgrading the steel pipe flaw detector machine equipment, while the latter method only needs to improve the magnetic saturation state device on the basis of the original basic instrument equipment to carry out flaw detection on steel pipes, etc., which has the advantage of low project investment. According to general rules, the larger the specification, the thicker the wall thickness, and the softer the magnetic characteristics of the raw material, the greater the required magnetization current, and vice versa. The basic magnetic saturator consists of a magnetizing electromagnetic coil and iron prefabricated components, with a large volume and clean weight. It is suitable for use in fixed sites in steel pipe manufacturing plants. In such situations, the magnetic saturation device does not need to be moved, and the volume and net weight do not need to be considered. Therefore, general raw materials can be used to make it to control costs. For customers who use steel pipes in power plants, petrochemical plants, and other industries, the steel pipe flaw detection machine equipment is generally installed on the spot of fluidity, rather than in the production workshop. In order to facilitate the application and movement of steel pipe eddy current flaw detection equipment, the device must be lightweight and efficient. In addition, the magnetized switch power supply adopts a constant current power supply with a voltage regulator, which can effectively prevent the drawbacks of changing the magnetizing current due to voltage changes during ultrasonic testing or overheating of the magnetizing electromagnetic coil, resulting in an increase in the resistor.
|