I have multiple 8711 ETFE liner with 316L SS electrodes (no bullet style heads...sigh) on a somewhat filtered water application and am tackling cleaning and recalibrating them. We have already changed a few out and it appears to be a 6-8 year build up of a rusty color film on the inside. I sent two off for a failure analysis and was told two months, but called Monday and was told it would be 4-6 more months....sigh. So I don't know exactly what it is but 99% positive it is iron/rust build up. So I contacted the manufacturer and they said use a damp cloth or some cleaner or solvent that is approved for the material the flow meter is comprised of but be sure not to scratch anything. I specified ETFE and stainless steel and they couldn't give me any recommendations. I then contacted our water guy and another testing/calibration company and they too provided me with no recommendations. So, next week I am taking 16 of these things out and calibrating/cleaning them and returning them to service. I only have 8 spares so I need to make sure that I can clean the units properly to get rid of the coating so they work better but not damage them. I am humbling looking for some field tested methods of properly cleaning the insides of a mag tube. These units are going to be removed from service so I will have full access to the inside and the sizes are 1", 1.5" and 2". Some what not to do things would also be appreciated as this is my first dealings with the magnetic flow tubes.

 

We can help! Shoot me an email with your contact information [email protected].

 

two types of cleaning methods have been used, ultrasonic and electrolytic.

The electrolytic cleaners are commonly used in "clean" water, the ultra-sonic where you have grease buildups, and commonly provided by the manufacturer.

 

Ah yes, but as Christian Dubbick, the chairman of the board of Krohne AG said to me, "Ultrasonic cleaning is like prayer, Walter. You must believe it is working."

Frankly, the best way to clean a magnetic flowmeter is to either pig it in place or remove it and physically clean it.

Walt Boyes, FInstMC, Chartered Measurement and Control Technologist
Life Fellow, International Society of Automation
Editor in Chief, Control and ControlGlobal.com
[email protected]

 

I can promise you that the use of ultrasonic cleaning by itself for electrodes in a grease application will fail! The ultrasonic cleaning attracts grease! It's a full bore meter pig it!

 

I dunno if ultrasonic cleaning attracts grease, but I can share with you something that Christian Dubbick, the founder of Krohne told me nearly 35 years ago. "ultrasonic cleaning is like prayer, Walter. You have to believe it is working."

Be careful of pigging a lined magmeter: go slowly and gently. Alternatively, build a bypass so you can pull the meter and service it.

Walt Boyes
Spitzer and Boyes LLC
3433 Connecticut St
St Louis MO 63118
[email protected]
office: +1-630-639-7090