Instruments : Developed for Crack & Grinder Burn Detection Testing of Component Parts
Digital Eddy Current Test Instruments with Unique Functions
The new ibg family of digital eddy current test instruments, with unique technology innovations, provides a simultaneous 100% inline test at an up to now unknown level of test reliability. Detection of grinder burn and cracks in the parts can be carried out directly in your production lines. Clear user guidance, an identical operating concept on all instruments and several operating languages will make it easy to make the most of our instruments. Whether it is the modular eddyvisor®, the compact eddyliner® or the top hat rail assembled eddyguard® - we have the right solution for each task.
Crack & Grinder Burn Detection
Digital eddy current test instruments for non-destructive testing of metal components, mass-produced parts and semi-finished products for cracks, pores and grinder burn using Preventive Multi-Filter Technology (PMFT) and Simultaneous Harmonic Analysis. The new ibg family of digital crack detection instruments offers a first -- simultaneous 100% inline detection of grinder burn and cracks in your production lines. Due to automatically generated 360Â° tolerance zones, testing in up to 30 band pass filters simultaneously and ibg's good-part-only calibration concept, you will detect defects, including grinder burn, that are missed by conventional instruments with a known-flaw-oriented setup.
Crack and Grinder Burn Detection on Bearing Rings
eddyvisor SC - Crack / Grinder Burn Detection and Structure Test in One Instrument
Digital eddy current test instrument for non-destructive testing of components, mass produced parts and semi-finished products for cracks, pores and grinder burn and for material properties such as hardness, case depth, structure, tensile strength, heat treatment or alloy using Preventive Multi-Frequency Technology and Simultaneous Harmonic Analysis. High performance modular concept with max. 16 independently working crack detection channels, max. 32 structure test channels and combinations of that in only one device. The eddyvisor® SC is recommended whenever you need an instrument to carry out inline test with several stations, both for crack and structure test.
Crack and grinder burn detection
Efforts to reduce content of valuable raw materials and of energy bring reduced cross sections in high volume components in the fields of mechanical engineering and automobile components. The resulting reduced cross sections and stricter material properties requirements have incentivized manufacturers to guarantee correct structure and crack and grinder burn free condition by increased nondestructive testing.
The eddy current test method can be applied for all materials with electrical conductivity or magnetic conductivity (permeability). This includes all metallic materials. The eddy current crack and grinder burn test can be adapted to many test tasks by selecting the suitable crack detection probe and transmitter frequency. As a matter of principle, mainly surface open or flaws close to surface and pores are detected.
Crack detection probe box for contacting testing on eccentric parts like camshaft lobes for cracks and grinder burn; large diameter range is covered; up to 300 rpm (depending on part geometry), ceramic supports for long life-time. Solutions for structure test on camshafts on request.
The test resolution and effective scan width of a crack detection probe is dependent on core size and type (between 0.5 and 5.0 mm). When testing, a relative movement of probe to surface of test part is always required. In order to test rotationally symmetrical parts for cracks, either the test part is rotated and the probe stands still or the test part stands still and the probe is rotated around the part by means of a rotating head. If more than one line shall be tested additional feed forward is needed. Thus complete surfaces can be scanned. More complicated surfaces require more complicated mechanical handling systems. Our own special machine manufacturing group is always pleased to work with you to design and build a test system for your 100% testing.
Steering nut in an automatic ibg test system. Detection of cracks and grinder burn defects on the race inside.
In the past the eddy current crack test would be set to optimally detect an artificially generated (EDM) defect master. But artificial defect masters show different eddy current behaviour (i.e., phase shift, etc.) than natural defects. Thus, natural defects could go undetected. Now the ibg technique with its eddyvisor instrument family walks on new paths. Thanks to the Preventive Multi-Filter Technology the instrument is not set to an artificial defect anymore but to the eddy current pattern of “healthy” surfaces of several OK parts. Automatically 30 tolerance zones over the entire spectrum of filter bands are formed which in fact picture the “healthy” surfaces in the test instrument. As soon as one of these tolerance zones are exceeded by the eddy current signal a NOK signal is triggered, no matter if caused by an artificial or by a natural defect.
For proof of test sensitivity, an artificial defect is put into an OK part by EDM processes. This defect must be 100 % detected by the instrument for validation of the method and of the test system. The limit defect of your application is determined beforehand in our lab during a feasibility study. It results in definition of direction and dimension of the smallest reproducible defect that must be 100 % detected without or without significant pseudo rejects.
The well-known note “surface to be free from cracks” on drawings suggests a wish for perfection of the part ibg lathe for lab tests, feasibility studies and small series in crack detection with eddyvisor. Speed max. 850 rpm, chuck up to 68 mm diameter, with trigger sensor, flexible probe movement. to be produced. However, there are physical limits of the eddy current crack detection relative to that wish. We have committed ourselves to move these limits further in the direction of smaller, detectable “discontinuities” without increases in pseudo rejects and under production conditions. The exploitable sensitivity of the eddy current crack test depends on several parameter:
ibg-lathe for lab tests, feasibility studies and small series in crack detection with eddyvisor. Speed max.
ibg mainly applies differential probes for crack detection. The differential principle reduces the very large receiver signal almost to zero by use of two compensating counter rotating receiver windings. This enables very high amplification of very small signals from flaws without overloading the input of the test instrument. Furthermore, ibg places high standards for precision for its own probe manufacturing, further enabling higher amplifications. On the noise side, ibg instruments employ extremely low noise signal processing, earliest possible digitalization and smart signal processes. Thus, ibg is able to combine very high flaw signal amplification with very low noise signal processing allowing larger distances between test probe and test surface without loss of test sensitivity. The advantage realized is that ibg test probes can be held 0.7 mm
Grinder burn detection
As per ISO 14104, grinder burn is a local overheating of surfaces. Heat impact during the grinding process was too much and effected localized annealing or, if heat impact was still stronger, there can be re-hardening zones. Depending on part surface quality and geometric influences, the ibg PMFT detects grinder burn with detection beginning at the level of mere change in residual stress or beginning of annealing zones in the microstructure.
A method applied by ibg to produce reference samples for grinder burn detection is laser burn: heat, defined and locally applied to the surface of the test part. Thus, producing defined artificial defects of different intensity in metallic parts which show analogue features like real damage. They can widely be produced and reproduced at defined spots according to requirements (kind and depth of structure change, spacial dimension) and they serve as master part for validation of automatic test machine as well as for determination of sensitivity of a test systems.
Features crack and grinder burn detection
Crack test on 6 positions of a wheel hub, with scanning of the inner and outer surface. Each segment has a set of reference data based on good parts, which are used as base for the tests. The eddyvisor shows the tested segments in colours according the obtained test result.
Highest test reliability and sensitivity – different kinds of probes for crack and grinder burn detection. Back left a rotating head eddyscan H rotating head for testing a string of parts and bars,