ect MAD 8D RELEASE 8.00
Version 8.00 of the ect MAD 8D software in all option configurations is now available. With the release of Version 8.00, we have changed the product name from MAD 4D to MAD 8D. This name change was necessary because the number 4 is very unlucky in most Asian countries. The number 4 is so unlucky that many hotels do not have a fourth floor. The number 8 means prosperity.
THOUSANDS OF INTERNAL PITS IN HEAT EXCHANGER TUBING
When pitting occurs in heat exchanger tubing, usually there are hundreds or thousands per tube. The task of manually examining the eddy current response to each of these signals in order to determine the deepest defect in a tube is immense.
Computer-aided, automatic sizing of these defects is the answer. For further information, please request the report
AUTOMATIC SIZING OF INTERNAL PITS IN HEAT EXCHANGER TUBING USING EDDY CURRENT.
QUASI ON-LINE EDDY CURRENT ANALYSIS
"We are very glad to tell you that in the October [1996] issue of INSIGHT, we published a paper on "A new method for quasi on-line eddy current analysis: wavelet transform". The experimental work for that paper was performed with your [computer] based MAD 4D, as can be read in Point 3 of the paper.
We would like to point out that at the lab, we also have equipment from Zetec, namely the MIZ-20, 22 and 40. However, we selected MAD 4D because it is PC-based and allows data handling under DOS." . . . Marta Ruch, Comision Nacional de Energia Atomica, Argentina.
WHY DO SOME EDDY CURRENT INSTRUMENTS FAIL? MARCO HELPS KEEP COOL IN THE HEAT DETECTION OF CIRCUMFERENTIAL CRACKS IN HEAT EXCHANGER TUBES EDDY CURRENT TRIVIA -- HOW FAR SOUTH?
A few weeks ago I read an article in Electronics News that expressed concern about the shortage of, and rising price of, electrolytic tantalum capacitors. The article went on to express concern that as a result, some computer motherboard manufacturers were using the less expensive and more readily available aluminum electrolytics as the power supply bypass capacitor for the microprocessor.
Microprocessor manufacturers recommended the use of a tantalum capacitor. The article pointed out that tantalum capacitors have better performance specifications than aluminum electrolytics. Furthermore, aluminum electrolytics begin to degrade from the day that they are manufactured; whereas, there is no known degradation mechanism for tantalum capacitors. At Eddy Current Technology Incorporated, we have never put an aluminum electrolytic capacitor in any product. We have always used tantalums, but not just any tantalum. We have never used the cheaper, epoxy dipped tantalums; but instead, as a minimum, we have always used a hermetically sealed MIL style CSR13 capacitor (the R in CSR13 stands for established reliability) designed to MIL SPEC MIL-C-39003.
The tantalums we use are rated for full performance over an operating temperature range of -55° C to +85° C and yet we still derate them. That is to say when we choose a capacitor for a specific application, we will choose one with a voltage rating which is at least 25 per cent higher than the operating voltage in the circuit.
After all that, we still burn in the finished product prior to shipping it to the customer. These are all reasons why we get reports of reliable performance of our products from the snow country of Canada to the heat of Saudi Arabia.
We may pay more for our electrolytic capacitors than our competitors, but there is payback. In 18 years of business, we have had only one field failure of an electrolytic capacitor. This was entirely our fault. We installed it incorrectly. Since that time, we have added an additional inspection which is performed immediately after burn in, which has successfully prevented us from making this mistake a second time. No customer has ever paid a repair charge to replace an electrolytic capacitor in a product manufactured by Eddy Current Technology Incorporated.
If an electronic product is designed and manufactured correctly, it should never fail, and there is no need for an Owner/Loaner Guarantee.
Maintenance of Air Conditioning and Refrigeration Company, Limited, of Riyadh, Saudi Arabia, purchased one complete ect MAD 4D eddy current system in the month of September, 1994. Since then they have used this system for the inspection of many air conditioning systems.
Ghaleb Abu Sa'a, Branch Manager: "In particular, we wish to record here the jobs that we recently carried out with the ect MAD 4D eddy current system. In one of the major hospitals in Riyadh, King Faisal Specialist Hospital and Research Center, there are four 2,500-ton Turbo Master Centrifugal Chillers. The customer contracted us to carry out the eddy current tests on these chillers. All condensers and coolers have been checked with the ect MAD 4D eddy current system, and the results were found to be accurate. We were able to repair and replace the defective tubes successfully based on the reports that were produced from the ect MAD 4D eddy current system."
"We also wish to mention that during the peak summer in Riyadh, the temperature reaches up to 50°C in the shade. We do not face any problems with the ect MAD 4D eddy current system working under these severe temperature conditions."
The detection of circumferentially oriented cracks in heat exchanger tubing is difficult to detect with the usual bobbin probes for two reasons.
1. The bobbin coil creates eddy currents in the tube wall which flow in the circumferential direction; therefore, they pass a circumferential crack without having to cross its crack face. This gives a low sensitivity to this defect type.
2. Most circumferential cracks are located adjacent to support structure or an expansion transition, both of which create a very large signal, masking the small signal from the crack. Circumferential cracks occur in several heat exchanger applications as follows:
1. At the tube sheet expansion transition zone in nuclear steam generators.
2. On bends that occur in nuclear steam generators at the top of the sludge pile.
3. In nuclear steam generators at the top edge of the top support plate.
4. In titanium condenser tubes at the tube sheet expansion transition zone when the tube was overrolled in the tube sheet.
5. In finned copper tubing (integral fin) used in air conditioners. The crack initiates from the root of the fin and may or may not be in an expansion transition zone, but even away from expansion transition zones, the tube has high background noise, masking the signal from the crack.
6. Fatigue cracks mid-span between support plates on the peripheral tubes of titanium condensers.
In 1983, Eddy Current Technology Incorporated designed the first probe in the world that was capable of detecting circumferential cracks at a tube sheet expansion transition zone. The probe design canceled signals from expansions, support plates, and tube sheets, while increasing sensitivity to circumferential cracks by having current flow in the longitudinal direction in the tube, so that the current flow would pass over the crack face. For further information on this subject, please request the report DETECTION OF CIRCUMFERENTIAL CRACKS IN HEAT EXCHANGER TUBES.
"In 1984, I was preparing to move Eddy Current Technology from its original location of Fredericton, New Brunswick, Canada, to Virginia Beach, Virginia, USA. One reason was that I was tired of snow country and wanted to live some place warm. That seemed to raise the question would Eddy Current Technology Incorporated then be the farthest south of all multi- frequency eddy current equipment manufacturers in the world?
I consulted my World Atlas. I was not surprised to note that in Fredericton, Canada, we were already further south than the other manufacturers in England, France, and Quebec. What surprised me was to note that in Fredericton, we were already 100 miles further south than the manufacturer in Seattle, Washington, USA. Eddy Current Technology Incorporated relocated to Virginia Beach, anyway, and it is a wonderful place to live and work." . . . Monty O'Connor, President, Eddy Current Technology Incorporated.
