I've not seen this thread before, so a few more tips for you

(also my apologies if I say something that has already been mentioned!)
Your bellows look good, but they won't work with coke I'm afraid. Coke needs a pretty constant draft to burn and I haven't found even a pair of larger bellows to be much use unless I have somebody pumping them constantly. A hand cranked blower will work fine though. With bellows you really want charcoal,but even coal will work better
The bottom of you forge will want to be filled in to the level of the pipe and then up the sides so that you don't have a lot of wasted fuel and burn out your pipe on the first day. You can use wood ash or clay happily enough there
Your pipe (in this case more akin to a blast grate rather than a a tuyere as the air is coming through a series of holes not out the end) will work fine, but close off all but a couple or three of those holes. That large a surface area will give you a massive hot spot that will consume a lot of fuel and toast you in the process. Also the larger the hot spot, then the deeper your fire needs to be to make sure that you aren't heating in a highly oxygen rich area (this burning your steel and losing more metal to scale that needed).
one way I have found of cleaning ash out of a pipe forge like that (I hve had a couple or three over the years), is to put a large washer on the end of a bar and leave it in the pipe, so the washer is at the far end and the par is sitting where your bellows plug in. That way when you are done or the ash blocks the holes, you can pull the bar out and clean the ash out at the same time. Make sure though that the washer is a lot smaller than the pipe (say a 20mm washer in a 30mm pipe), otherwise the scale that will form on the inside of the pipe and the burnt ends of bar that drip through will block the passage of your washer.
the suggestion of damping the fire with water to limit the hot spot to where you want it is a good one, but I've found a dribble much more useful than a misty spray. Some folks use a tin can with holes punched in it, I use whatever ladle or coffee cup is to hand!