A large Philadelphia tank farm was contracted to distribute candle wax and provide bulk storage. The wax was pumped from ships to a large heated storage tank. The viscous fluid was then pumped to rail cars and tank trucks for distribution. The problem was that the storage tank had to be kept relatively cool to avoid damaging the product. But, it was too cool to be pumped at a reasonable rate. Solidification in the transfer lines was also a problem.

F. S. Welsford Co. provided the solution. An Alstom Model #HST-2-24-96 heat exchanger was selected to heat the product with steam. This particular unit was designed with special internal baffles to efficiently heat the viscous fluid. The unit was also designed with a special stand and housing so that the tube bundle could be removed for inspection or repair. Accurate temperature control was critical, so a Partlow temperature controller was used, hosed in an explosion-proof box. This used a Reotemp RTD and a Jordan Mark 75 steam control valve to complete the loop. F.S. Welsford also provided the steam block valves and Bestobell float and thermostatic stream trap.

The customer was able to freely pump the wax for quick tank truck loading without overheating. The components were designed to work together ensuring trouble free operation. The customer also enjoyed field support from one vendor for startup and one invoice for almost all of the the components needed for the project.