I wonder if there is a reliable diameter gauge. Sikora and Zumbach only used for reference.
Thanks

Well that is the most remarkable, non-technical statement I have heard in the last 35 years!

What diameters are you trying to measure and at what speeds? What kind of gages are they? What vintage? What is the accuracy you are looking for? What kind of machines are they mounted on? Is the measured surface smooth, corrugated or bumpy? Are you using SPC? Is there contamination on the wire or cable? (Water for instance.) Is the wire or cable vibrating? What is the environment in the plant. Are the units checked and calibrated on a regular basis? Are the units looked after and kept clean, particularly the lenses? How often are they calibrated and have the machines ever drifted in their readings? If so, by how much? Are there any meaningful records or is this just talk around the water cooler? Do the manufacturers know what you are trying to measure? Have they seen the logs pertaining to their machines? And on and on and on!

Sincerely,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com

Don't be so harsh, Peter, not everybody has well over 30 years of manufacturing experience under his belt.

I think Antonio is referring to insulation diameter/cross section measurement which is one of the real important issues in cable manufacturing.
As we all know, the vast majority of cost in cable manufacturing lies in the material. To generalize, roughly 70% is copper 30% insulation material. This will vary depending on cable type.

To simplify, present measurement methods, statistically speaking, result in over dimensioning of the insulation by at least 5 – 7%, hidden from the manufacturer due to the inadequacy of measuring methods.

ACM of Sweden has developed the award winning KSM off-line measuring and database system which not only provides the user with a highly accurate (0.2%) measurement of diameter, walls and cross-section, but also compiles all this data in an easily accessible database complete with trend curves, cost of over dimensional insulation and much more.

Check some of the KSM features on www.howarequipment.com/Measuring.htm

Best Regards,

Willy Hauer
Howar Equipment Inc.
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Thanks for your comments Willy, I wasn't really trying to be harsh but a broad statement like that is so very hard to swallow.

It is my understanding from public documents however that Antonio in fact has over 30 years experience in the wire and cable industry himself but not in a technical role.

It is not clear that Antonio was referencing power cable insulations because it certainly looked like a broad brush denouncing diameter monitors in general. Diameter monitors are really very good instruments but they are indeed diameter monitors and nothing more.

To look inside a cable or to infer what is actually going on inside a cable or wire insulation, one obviously needs other equipment or instrumentation. Some on-line external instruments can also lie to you. A classic example of this is a capacitance monitor watching for capacitative variances in cellular polyethylene insulation. The variances can be of course for two different reasons. (1) Off center and (2) changes in the specific gravity. An ACM instrument would not pick up the latter as it is not made for that.

I agree with you Willy that the ACM machine is a good instrument. As you know, eccentricity of the conductor and the various layers of insulation and shields can and does result in plastic overages not immediately noticeable to the cable manufacturer. What the manufacturer sees however is the negative materials variance and that should be the alarm bell that something is very wrong.

As far as my experience goes Willy, you would laugh. A little over 30 years ago Stefan Askenfors and I were tramping around northern Sweden to look at the Ericksson Pitea telephone cable plant that has now been closed for decades. I don't know if you ever saw their two "Monte Carlo" machines for randomly positioning pairs in S-Z stranded cables in that plant. They were remarkable pieces of creative engineering but easily replaced today with a microprocessor based random function generator. There should be an on-line museum showing photographs of long abandoned classes of wire and cable machines and instruments. Perhaps when I retire, if ever.

Willy, has ACM (Stefan) ever given a paper showing the benefits of their equipment even if the CV line is equipped with X-Ray diameter/eccentricity monitoring equipment which is being used in a continuous sampling SPC program? That I would like to read.

I have actually seen operators "dial-in" the eccentricity of power cable insulation on the fly at start up by looking at the X-ray graphical display on a CRT.

Best Regards,,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com

Peter,

Is Lear Engineering still in business? I bought a laser mike from Dennis Swing about 1979. At that time it was good to 4 places but the last place would only be a 5 or 0 such as 0.0645 or 0.0645. As it improved the last place then became 0-9. In later years Dennis started his own company Lear Engineering I think in Dayton OH or there about. He had a hand held measuring device which was quite good for magnet wire even the very small sizes. Don't know what this guy is measuring but perhaps he just doesn't have confidence in the equipment.

When I was traveling way too much I was paying a bill in a restaurant. After calculating the bill with the computerized cash register, the clerk check his figures with an abacus.

Hi Spectre,

Yes Lear Engineering is still in Dayton, OH and Mr. Dennis Swing is the president. They are at www.learengineering.com/

What Willy Hauer was referring to was the ACM AB (Sweden) off-line, optical, cable cross section measurement equipment. They are located on the web at www.acmab.com/ This equipment shines when used to measure the three simultaneously extruded plastic layers of power cable. A technician takes a short piece of the cable, removes the conductor, and then uses a microtome to get a thin slice of the plastic cross section. This cross section is then optically analyzed by computer for minimum wall thicknesses etc. It is a very niece piece of equipment that works well. It is however off-line and not a continuous diameter/ eccentricity monitor.

The X-ray equipment I was referring to is the Zunbach triple layer, on-line, X-ray measurement equipment (Rayex) at www.zumbach.com/e/product/rayex.asp and the Sikora triple layer, on-line, X-ray measurement equipment (X-Ray 2000) at www.sikora.com/

Best Regards,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com