-- The Home Page of the Finishing Industry

on this site
current topics
Live! From beautiful Pine Beach New Jersey: Welcome to the world's most popular metal finishing website

topic 18415

Aluminum Heat Exchanger


A specialty type of the heat exchanger, extruded from the aluminum alloy, has developed within its inside channels deep groves. The understanding is that the groves are the result of combination of corrosion, chemical and oxidation, and erosion caused by flowing water. It looks that the erosion takes over once the corrosion makes initial progress braking the otherwise smooth surface. Can the heat exchanger be sand-blasted internally, or cleaned in some other way, and coated to prevent further progress of the erosion/corrosion?

Stan Blovish
- Toronto, Ontario, Canada


Dear Stan,

Yes you can do it by chemical conversion named alkaline chromating. Our company did it for air type heat exchanger of power is an old processes but the time anodizing is impossible it is a substitution. It protect inside and outside of heat exchanger . To start look for MBV processes.

Hadi Khosarvi
- Tehran, Iran


Dear Hadi,

We greatly appreciate your advice. Stan is away and I will continue the project to its final completion. Can the MBV method be applied at the site, without dismounting the heat exchanger and moving it to a factory? The heat exchanger is constructed with over 100 aluminum extrusions, which are cooled with water independently of each other. Each extrusion may be depicted as a hanging U-tube with both openings at the bottom. The length of the 'tube', up to its U-turn, is about 13 m and the size of the openings is about 25mm x 80mm. What was the reason for your company to use the MBV method on the heat exchanger? Was it corrosion or only erosion? We have mineral and oxygen corrosion problem and I am still concerned about the possibility that the erosion remains the biggest problem. Thank you in advance for your comments.

Gregory Szewczyk
- Toronto, Ontario, Canada


Dear Gregory

Sorry for long silence. The reasons for MBV comes from the need to protect the Al alloys from corrosion . as mentioned in my last letter first you have to chose appropriate alloy to get maximum coating thicknesses and erosion resistances. Unfortunately the MBV process can not be immersed at site. You need baths sized to accept the largest existed and dismantled components. Please inform us any how in order to start from alloys material selection ,pretreatment and post-treatment. The production rate of heat exchanger is also the main reasons to decide to invest for this type of coating. It is still the best practical way for al heat exchanger. In case if you need more information please do not hesitate to contact.

Hadi Khosravi
- Tehran, Iran


Have you given any thought about purchasing pre-coated heat exchanger aluminum finstock? We supply pretreatments and coatings for the aluminum coil coating industry. Many of our customers sell their coated aluminum to coil forming shops that make air conditioners, etc. Precoated finstock will inhibit the galvanic corrosion you are describing. Lateral corrosion from the bare edge inward could be a concern depending on the environmental conditions but this mechanism usually takes several years to notice.

Mark Thompson
- Charleston, South Carolina

If you have a question in mind which seems off topic, please Search the Site

ADD a Q, A, or Comment on THIS topic START an UNRELATED topicView CURRENT HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2019, Inc., Pine Beach, NJ   -   About   -  Privacy Policy
How Google uses data when you visit this site.