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Ted Mooney, P.E. RET
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Corrosion problem in zinc plated telescoping tubing
June 24, 2011
WE ARE A OEM MANUFACTURER OF LINEAR ACTUATORS. WE USE HRPO WELDED ROUND TUBING.
OUR PRODUCT REQUIRES A 2.00" OUTER TUBE AND 1.75" INNER TUBE TO ALLOW TELESCOPING.
THERE IS VERY LITTLE CLEARANCE BETWEEN THE 2 SURFACES.
THE OUTER TUBE IS E-COATED WHICH DOES NOT COAT THRU THE ENTIRE LENGTH. TYPICAL TUBE LENGTHS ARE ABOUT 36" LONG. THE INNER TUBE IS ZINC ELECTROPLATED AND HAS A LACQUER SEAL.
THE PROBLEM IS THAT WE HAVE AN OUTDOOR APPLICATION WHERE PRODUCT IS STORED OUTSIDE FOR A PERIOD OF A FEW WEEKS. AFTER INSTALL THE INNER TUBE SURFACE IS ALREADY RUSTED.
WE HAVE SHIPPED THOUSANDS OF THIS TYPE PRODUCT AND NEVER HAD A PROBLEM UNTIL THIS SPECIFIC CUSTOMER.
SEE PHOTO
ANY SUGGESTIONS AS TO WHAT IS GOING ON??
I REALLY APPRECIATE YOUR ASSISTANCE.
THANKS IN ADVANCE.
OEM - DAYTON, OHIO
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