Cover Story
Exchangers ’ quality services
When cleaning a heat exchanger , 40,000 psi is used , which is very dangerous . Dunn Heat Exchangers changed its safety reporting protocol and model to directly address this issue . “ We do not want anyone manually using this , we want all of our employees outside of the line of fire . We have switched to a behaviour-based safety model . Before , we would celebrate milestones without reportable incidents , but what some did not realize is this encouraged people not to report . This new model rewards individuals for good safety practices , which is what we are all about . We have seen really positive changes , and every single person in the company is thinking about safety .”
“ We have switched to a behaviour-based safety model […] We have seen really positive changes , and every single person in the company is thinking about safety .”
The main customer base of Dunn Heat Exchangers is midstream and downstream oil & gas , followed by power generation .
Quality services and safety : a one-stop-shop The company has had many major milestones over the years , one most notably being the ability to clean heat exchangers off-site . “ In the past , heat exchangers have always had to be serviced and cleaned on-site . Large pumps and equipment would have to be brought inside the plant , and then be manually operated . This was a very high source of accidents and fatalities , because of dealing with high-pressure water ,” said Pete . “ We saw that it was necessary to start cleaning off-site . We developed our own equipment , ways to transport the dirty equipment without leaking the contaminants , and create a way to clean which is easier , faster , cheaper , and most importantly , safer .”
After cleaning an exchanger , there are often issues that need to be addressed and repairs that need to be made . “ The machining is precise , and even the welding processes must be overseen for heat exchangers . It takes specialized tools to do so , therefore , a lot of the things we use in our fabrication process , we also use in the repair ,” said Pete . “ This is very convenient for customers , because immediately after cleaning , we can begin inspection , repair , put them back together , and get them back inside the plant quickly . This saves time and prevents the client from having to source several contractors ; we are essentially a one-stop-shop .” Dunn Heat Exchangers is a TEMA ( Tubular Exchanger Manufacturer Association ) shop . “ Many TEMA shops will produce similar quality , as they are following the same standards ,” said Pete . But what sets Dunn Heat Exchangers apart is the overall quality package : “ We are the only company that has offered off-site services continuously since 1960 . We are a very large company , and we are also the only site that does not recycle process water .” This can be a big quality issue for plants . When building with stainless steels , they are looking for hydrotests with water . “ A lot of people do not realize that when cleaning a heat exchanger , the same level of purity in water is needed . A high chloride water could cause the same problems that one is trying to prevent ,” said Pete . “ We make our own demineralized water here , with our own units to take chlorides out . When recycling process water , most things coming out of plants will be slightly acidic or basic . Neutralizing those PHs essentially creates salts , and there is no way to filter this out when recycling the water . Using this water to clean may cause corrosion www . heat-exchanger-world . com Heat Exchanger World February 2023
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