Total 17 sets hairpin heat exchangers for Pakistan National Refining Upgrade Project in Karachi have been completed and delivered successfully on Jan.7th 2016, which is domestic first lot of hairpin exchangers with ASME U Stamp.
There are 4 sets of equipments in critical corrosion condition (wet H2S), this is the first time in recent two years for Sunpower to undertake the project with such conditions which have very special requirements to the materials, it is required that all the components in directly contact with medium or directly welded to pressure parts shall meet the requirements for chemical composition and be approved by HIC test ( test period is 96 hours and with high cost, only three research institutes have this qualification in domestic China); for another large diameter equipment, its material is relatively rare, preheating and hydrogen elimination are mandatory before and after each welding process, its manufacturing process is complicated and with high difficulties. In contrast with the hairpin exchangers we did before, the seal structure for these equipments are more innovative, the use of metal washer guaranteed the sealing effect for equipments under condition of high temperature and pressure.
The successful completion reflects our high ability for design and fabrication, which has a extraordinary influence on our position in the domestic chemical industry and manufacturing industry.