Harben Inc. was recently tasked with the challenge of Hot Dip Galvanizing a trailer jetter frame. Since we were somewhat new to the process we had several questions: What exactly is Hot Dip Galvanizing? Why would we want to galvanize a jetter frame? How much does the process cost and will it add value for the customer?
Why Hot Dip Galvanize Steel?
The short answer to this question is durability and longevity. Atmospheric conditions in the Northern States, East and West coasts and Canada wreak havoc on steel. Salt on the roads during long winters and the salty ocean air can both corrode steel at an amazing rate, but galvanized steel corrodes at a rate of about 1/30 of untreated steel. While there is no definitive answer on how long galvanized steel will last, it is expected to last for approximately 50 years in most common rural environments and 20-25 years in more severe urban and coastal environments.
What is Hot Dip Galvanizing?
Simply put, it is the process of dipping fabricated steel into a vat of molten zinc. The steel metallurgically reacts with the zinc to form a tightly bonded alloy coating that provides superior corrosion protection to steel. The process of Hot Dip Galvanizing is rather simple: the fabricated steel frame is bathed to remove any existing oil and grease, the frame then goes through a process called ‘Hydrochloric Acid Pickling’ to remove the rust and scale and it is then rinsed with water and dried. Finally, it is dipped into the molten zinc having being prepared to ensure that it is fully submersed in the vat to ensure that both the inside and outside of the frame are fully coated and it does not just float. The steel frame is then extracted from the vat at a controlled rate allowing the outer layer of zinc to solidify, forming a relatively pure zinc coating.
Is it expensive and does it add value?
One of the benefits of Hot Dip Galvanizing steel is that it is lower in cost than many other specialist protective coatings. Although the process costs approximately 20-30% more than a powder coated, painted frame the benefits far outweigh the costs. These include:
- Longer Service Life: Up to 20-50 years, depending on location and conditions
- Tough Coating: Metallurgic structure gives outstanding resistance to corrosion
- 100% Coverage: Zinc coating covers corners, sharp edges and inaccessible areas
- Faster Assembly: Coated frames and parts are ready for immediate use
The added zinc coating does mean that the final color of the frame cannot be predicted. However, Hot Dip Galvanized steel may be painted, but an additional cost will be applied. This process is known as a ‘Duplex System’ and can double the life of the protected steel. In some cases this could mean a service life of up to 100 years.
Our experience with this method has been a huge success as the finished product is easy to handle and our customers have been satisfied knowing that their investment is well protected for years to come.
If you require further information about the Hot Dip Galvanizing process or would like to know if it is the right choice for your next jetter please contact us.