When I decided to upgrade my brewery I knew I was going to be replacing my boil kettle and hot liquor tank. The Electric Brewery uses all Blichman kettles and weldless fittings. I had initially considered going this route, but then I discovered Spike Brewing and found that for the price of a Blichmann 20 gallon kettle that I would then have to add weldless fittings to, I could get a 20 gallon kettle with all welded fittings including a 1.5" tri-clover fitting for the heating element and I was sold.
I exchanged a couple of emails with Ben, the owner of Spike Brewing, and we settled on this design:
I procured a 50' x 1/2" stainless steel coil (12.5" diameter) and all necessary plumbing fittings from Stainless Brewing.
The final product turned out nice. Here's the tri-clover fitting for the heating element:
And a picture of the inside showing the coil connected via compression fittings and the water inlet port: