Process of corrosion coupons manufacturing : salient features
Using an allen key, unscrew the set screw on the coupon holder nut. Then remove the coupon holder from the solid plug (please note: the coupon
holder's threads are'left handed'). If necessary, brush the coupon holder and wipe it clean.
From the solid plug, remove the primary packing and O-ring. If they are found damaged, deformed or worn out on inspection, replace either or both parts.
Then reassemble the solid plug, tightening the coupon holder nut till the point when it snugly holds the primary packing
(note: don't allow the primary packing to spread open).
Using the Allen key, tighten the coupon holder set screw.
Now firmly tighten the coupons onto the coupon holder. Note : Person handling the coupons should be wearing a pair of clean gloves.
The assembly should be inspected to make sure that it is firmly tightened with no loose parts.
If strip coupons are utilised, the coupons’ orientation should be clearly marked, using a metal file, on the HEX of the solid plug.
On the solid plug,the threads and O-ring should be wiped with grease.
Now, the coupon holder assembly is ready to be placed in the access fitting body. The service valve and retriever must be utilised (in pressurized systems)
to install the solid plug with the coupon holder attached. The instructions in the Crystal Industrial Operation manual should be followed.
Before you finally tighten the plug in the access fitting should make sure that the coupons are aligned parallel to the process flow.
(Note: do not loosen the solid plug to achieve orientation, as this may affect the plug seal inside the access fitting).