Why does a dry break have to be threaded?

With all the liability issues, & HazMat regs, any quick-release load/unload fitting sounds really, really sketchy. I doubt the major terminals would let you load fuel with that kind of setup. And, the brake interlock paddles come into play too.

 

A dry break has a big flat disc, w/ outside mating flange that corresponds to the exact opposite flange on the loading arm...male & female if you will. There is a sliding collar that aligns the two...& when a lever is turned, the non-truck side of the assembly depresses the truck side disc, thereby opening the manifold to receive product & locking the two flanges together...all sealed up with O-rings, etc. No leaks upon hooking up or disconnecting ( with any luck ). When loading Gas, Diesel, Jet etc , the outer connector generally ( always in my experience ) depresses a paddle / lever that sets the trailer brakes so you cannot pull off the rack still hooked up to the loading arms. Some trailers also have the safety device on the vapor hose.

Same idea as the hydraulic hose connector on an end-dump. or low-bed, only more sophisticated.

A 4" hose under enough pressure to load 8000 gallons of liquid in about 15-minute can create a disaster in seconds.

 

Maybe I'm not understanding. I don't think you would want the drybreak affixed to the manifolding via camlok. It should be a threaded fitting that cannot come off easily. I haven't checked lately but EMCO-WHEATON or Parker-Hannnefin websites should show somethin'. The terminal side of the drybreak is not a camlok affair at all. Check out some pic's of a rack & you'll probably see what I'm describing.