Corrosion And Cracking
HEAVY METAL & TUBES
Carbon Steel ▪ Alloy Steel ▪ Stainless Steel
Perfect blend of
quality and integrity
bundle are hydrotested to demonstrate mechanical integrity. This is a perfect opportunity to introduce a vapor phase corrosion inhibitor. The inhibitor is added to the hydrotest water at between. 5 % and 3 % by weight volume and mixed to obtain a homogeneous solution. After hydrotest, the solution is drained leaving behind a volume that is saturated with the inhibitor molecules and a molecular film adsorbed onto the surface of the metal. Normally this does not require removal prior to operation. The other method of providing corrosion protection to the shell and / or tube side of a shell and tube heat exchanger is to fog with a vapor phase corrosion inhibitor when not in operation, such as during shipping, warehouse, and shutdown periods. The product is applied at. 3 oz./ ft3-. 5 oz./ ft3(. 31 L / m3-. 52 L / m3) as an alternate to nitrogen. Both the hydrotest additive and the fogging product provide protection by displacing moisture from the metal surface( hydrophobic) and being adsorbed( ionic, covalent, or metallic) onto the metal surface creating a microscopic barrier film which does not impact the material properties and normally does not need to be removed prior to operation. In layperson terms, the inhibitor molecules interact with positive and negative charges on the metal surface creating a net“ 0” surface charge, with no free electrical charge for corrosive elements to interact with a corrosion cell that cannot initiate.
References:
1. Understanding Galvanic Corrosion: Concepts, Causes and Prevention.( February 14, 2024). In Metal Failure Mitigation. Understanding Galvanic Corrosion: Concepts, Causes, and Prevention | The Armoloy Corporation 2. Failure analysis of stress corrosion cracking in heat exchanger tubes during start-up operation.( May 2015, Pages 1 – 8). In Engineering Failure Analysis Volume 51. Failure analysis of stress corrosion cracking in heat exchanger tubes during start-up operation- ScienceDirect 3. Shopia Ketheeswararajah,“ Corrosion and Cracking of Stainless Steel,” Stainless Steel World Americas, March 4, 2024.
What differentiates HMT from others
Carbon Steel, Alloy Steel & Stainless Steel from same mfr. Capability to mfr. st. length tubes upto 34 Mtrs. U-Tubes with max. hydro test pressure @ 700 Kg / CM 2 Special grades with quick delivery | SA334 Gr. 3, SA213 T5 / T9 / T91
Duplex & Super Duplex, TP310 / TP321H / TP347H / TP405 / TP410
Website: www. hmtl. in Email: info @ hmtl. in, mkt @ hmtl. in, exports @ hmtl. in Mobile: + 91-90165 49266, Tel.: + 91 90812 55991 / 92 / 93 www. heat-exchanger-world. com