PRODUCT REVIEWS Corrosion CUI inhibitor
Corrosion under insulation ( CUI ) is a long-time issue for petrochemical , refinery and marine environments . It happens when moisture and other corrosive media enter insulation after water barrier wraps or jackets are compromised or when condensation builds up , often unnoticed , beneath the insulation . This is particularly a problem with piping that undergoes wet-dry or high-low temperature cycling .
The threat of CUI is potentially even greater on offshore platforms or in other marine environments where chloride-rich sea spray can infiltrate the insulation . The longer CUI goes unnoticed , the more serious it becomes .
“ The problem is so bad that an estimated 40-60 % of piping maintenance costs in the oil and gas industry stem from CUI-related expenses . Even worse , undetected CUI on pipes carrying hazardous liquids may lead to leaks and potential explosions ,” explained Cortec ® Corporation .
To tackle this issue , Cortec ® Corporation has developed CorroLogic ® CUI Inhibitor Injection , new high-temperature , Vapour-phase Corrosion Inhibitor ( VCI / VpCI ®) technology that simplifies protection for insulated pipes reaching a high range of temperatures . It can be injected directly into insulating material . The corrosioninhibiting vapour migrates from the injection point along the pipe to form a hydrophobic protective layer on metal surfaces beneath the insulation .
“ This passive layer is long-lasting , protects in the presence of chloride-containing moisture and can withstand high temperatures of up to 662 ° F ( 350 ° C ),” outlined the manufacturer . It can only be applied after removing insulation or before insulating new pipes . Maintenance personnel can therefore apply protection under existing insulation , even on surfaces that reach high temperatures . This results in a wider timeframe in which to apply preventative measures , increasing the chances of inhibiting and arresting corrosion before it gets too serious .
A demonstration video , showing the hydrophobicity of CorroLogic ® CUI Inhibitor Injection , can be viewed at https :// youtu . be / ciyasehf6xk n
Free-cutting steel tubes
BENTELER Steel / Tube has succeeded in producing seamless tubes from free-cutting steel for the first time : the BENTELER SMARTCUT ®.
“ Free-cutting steel has been used for a long time as a solid material , mostly in the form of steel bar in the machining industry . This is because the material properties of free-cutting steel with a high sulphur concentration offer advantages in machining operations . This manifests itself in faster , more productive machining with better chip formation and longer tool life ,” explained BENTELER Steel / Tube .
BENTELER SMARTCUT ® combines the advantages of highly machinable , freecutting steels with the geometry advantages of a tube and thus optimises machining . The product line of seamless steel tubes , in hot-rolled as well as cold-drawn types , offers solutions for various applications in smaller quantities and for large-scale series production .
“ Due to production of the steel in an electric arc furnace , a reduction of the CO₂ footprint of more than 70 % can be achieved with BENTELER SMARTCUT ® ( compared to bar steel from the blast furnace route ). In
addition , the tubes are guaranteed leadfree in accordance with the EU REACH Regulation to protect the environment ,” explained BENTELER Steel / Tube .
“ Additional heat treatments ensure high strength with good formability . In addition , the tubes can be supplied with customised finishes , such as a machined inner surface or as a pre-cut short length ,” emphasised Bernd Mehren , head of engineering for seamless hot-rolled tubes .
With BENTELER SMARTCUT ®, BENTELER Steel / Tube is using the class of free-cutting steels for the first time for a product family of specific tube solutions .
“ With various sulphur content starting from at least 0.10 % sulphur — about three to five times the usual 0.015 to 0.035 % for machining tubes — BENTELER SMARTCUT ® tubes have excellent machinability . This means that the tubes can be processed better and more economically . Additionally , material savings of more than 50 % ( compared to steel bars ) are not uncommon ,” added Helwig Brabander , Head of Engineering Hydraulics / Precision , BENTELER Steel / Tube .
The company also cites greatly improved , short chip formation which has a positive effect on tool life ( reportedly up to four times longer ).
“ In addition , the material concept enables faster machining and , as a result of the stable process , automated machining which can reduce machining costs by up to 40 % in total ,” concluded Jan Schwarzer , the company ’ s sales director . n