failed tubes on exchanger unit . 2

[rsauk]

We are experiencing recurring failure on tube-ends resulting from erosive action of quench water being redirected at velocity from division plate on channel end.

Does any one have experience of providing 'sacrificial' barrier on tube sheet and including 25mm. into tube bore.
Tubes are tube-end welded.
The suggestion has been made to fit stainless steel clad sheet which would include ferrules into tube.

a second suggestion has been to provide a protective film
but of what material.

 

[Metalguy]

What are the tubes made from? There are various epoxy coatings which will probably withstand this erosion. They are applied pretty thick to tubesheets( ~3/8&quot.

 

[longeron]

There is a product called Condesner Tube Packing Rings that can also be used. It's a sleeve that fits inside the tube end to protect it from the fluid.

 

[rsauk]

have you any particular info ; about suppliers of ferrules within UK.

 

[Khan912]

You can install sacrificial anodes, and there is another solution too for tubesheet coating with epoxy paint.

 

[longeron]

I know that some pump packing companies carry this item. Try your local John Crane supplier.

 

[KeithMB]

I have successful experience of using nylon tube inserts in a sour water (water containing H2S)heat exchanger.

These were supplied by a UK company called Corrocoat Ltd. Contact was Simon Conroy tel 01132760760, website

http://www.corrocoat.com

They come in all standard tube sizes/gauges and are typically 4-6" long. Generally they are a tight push fit into tube or a adhesive can be supplied. They are specifically designed to overcome erosion/corrosion in first few cm's of exchanger tubes.

 

[chicopee]

About beefing up the size of the welds on tube ends? perhaps you could slow down flow of quenching water!!!
I suspect that there are several hundred tubes of small dia. so the question of beading and seal welding tube ends over the tubesheet is out of question.

 

[MJCronin]

rsauk,

Try these people:

http://www.plastocor.com/waterbox.html

let us know what you finally decide upon....

MJC