Apr. 15, 2017
Design & Operating Conditions - Equipment must not be operated at conditions which exceed those specified on the name plate(s).
Bolted Joints - Heat exchangers are pressure tested at JFD’s facility in accordance with ASME Code requirements. However, normal relaxing of the gasketed joints may occur in the interval between testing and installation at the job site. Therefore, all external bolted joints should be properly retightened (see diagram on page 8) after installation, and again after the unit has been heated. This is to prevent leaks and gasket blowout.
Operation Procedures - Before placing any heat exchanger in operation, reference should be made to the exchanger drawing(s), specification sheet(s), and name plate(s) for any special instructions. Local safety and health regulations must be considered. Improper start-up or shut-down sequences, particularly of Fixed Tube Sheet and Double Tube units, may cause leaking of the tube-to-tube sheet and/or bolted flange joints.
Start-Up Operation - When placing a unit in operation, open all vent connections and start to circulate the cold media only. Be sure the cold side of the unit is entirely filled with fluid before closing the vents. The hot media should then be introduced gradually until all passages are completely filled with liquid or vapor, whichever the case may be. Then close the vents and slowly bring the unit(s) up to temperature.
Start operation gradually. Do not subject the heat exchanger to sudden temperature fluctuations. Hot fluid must not be suddenly introduced when the unit is cold, or vice-versa. This could damage the exchanger and void the warranty.
For Fixed Tube Sheet units, fluids must be introduced in a manner to minimize differential expansion between the shell & the tubes.