Looks interesting for heating veg oil for filtering.....
Would this be better than somehow plumbing in a fphe?
http://cgi.ebay.com/Mueller-Temp-Plate-Barrel-Heater-Cooler-NEW-55Gallon_W0QQitemZ400062795661QQcmdZViewItemQQptZBI_Heavy_Equipment_Parts?hash=item5d2599cf8d
Well maybe to warm a real cold barrel. I have seen electric heat mats that wrap around barrels for the same purpos. This wouldn't be especially efficient as only half of this heat source is in contactwith the barrel... A FPHE would be way more efficient at getting a given ammount of heat into the oil than this would IMO.
I've used many of these in many plants...
The way they are used, is, you hook up a 250# steam hose to the inlet, and put a steam trap on the outlet. That heats up a barrel pretty quick, no matter how cold, even in Fort MacMurray... make sure to crack open the bung on the drum... ;D
Or, you can just crack open some steam and leave the outlet open to drain out the condensate.
These drum warmers aren't very efficient, and in my experience, don't last long, and aren't meant for continuous service. They're OK if you happen to have a boiler house capable of supporting a refinery or a steel mill feeding your steam hose... ;D