A large manufacturer of steel cables from Detroit, Michigan contacted Wattco with a problem that the cables they manufactured were corroding in their warehouse and needed a solution to prevent this from happening. Steel products that often sat in inventory for long periods of time were more prone to corrosion.
Traditionally, light lubricating oil was used to coat the cables, preventing rust from settling in. The cables were exposed to a steam heating tank, containing light oil at ninety-five degrees Fahrenheit. The problem was that the oil had a lower than average viscosity and tended to disappear after a period of time.
Oil immersion heaters
Oil that has a higher viscosity can solve this problem. It would coat the cables and offer a longer storage life than before
Oil that has a higher viscosity can solve this problem. It would coat the cables and offer a longer storage life than before. The trick was to heat it up to 220F, and make the oil more viscous without sacrificing the quality of the cables.
Wattco provided 12 immersion heaters, each with 9KW 480V 3PH that had control panels and a redundancy system that prevented downtime.
Thermocouples for heater safety
Two thermocouples were used – one for temperature control and the other for high limit shutoff to safeguard the heaters. The heaters were also overrated to provide the customer additional power available. 120,000 LBS of cable was able to be treated with oil reaching 210 degrees temperature.
Wattco suggested a high limit setting of 275 degrees to avoid overheating. This was easily programmed in the digital temperature controllers. Once we installed the new system, the process was monitored for 6 months and found no additional signs of corrosion.
Benefits include:
- No maintenance costs on process heaters
- Safety temperature controller that prevents overheating
- Cables are fully protected from corrosion
- Electric industrial heaters are fairly inexpensive and last for years
