By Brian Hall
Usually during this time of year, I would be asking if everyone enjoyed their time at the trade shows. Not this year. While it seems that we are coming out of this historic time, we still have a ways to go. While we weren’t able to see each other in person, I hope you took some time to attend the virtual sessions that were available at NPE and World of Asphalt.
As I was preparing for my virtual presentation for World of Asphalt last month, I ran across an old Blaw Knox Paving Manual that was about 25 years old. As I was thumbing through this typewritten museum of old knowledge, I couldn’t help but chuckle at some of the terms I ran across. The contents mentioned free floating screed, crown and valley as well as hot joints. The glossary contained antiquated words like flow gates, angle of attack and tow points. Wait a minute. These are the same topics I discuss in every Best Practices seminar I conduct. Am I that far behind in the trends? Nope. The bones are the same, we have just put fresher paint on the machine.
I was intrigued as I read further into this manual, so I decided to do a little more research. Of course, my research led me to the crawler-mounted Barber Greene 879 paver that was perfected after the great depression. The asphalt mix was received and carried in a front hopper, passed under the machine by means of a slat conveyor, distributed across the roadway by a screw conveyor, consolidated by a vertical tamping bar that vibrated at 1,200 strokes per minute, and finished by a rear screed. The machine’s design and slow speed compensated for irregularities in the roadbed, and it automatically produced a level mat of uniform thickness. What a concept. Sound familiar?
I can imagine though, that in those days, the paving professional was way less concerned about mat quality and rideability tests as we are today. They were probably so excited to not have to dig their car out of a muddy tire rut that they forgave the occasional mat inconsistency. I also can see the inspector following the machine and telling the operator exactly what he is doing wrong.
Let’s fast forward to my Blaw Knox manual of the ’80s and ’90s. It describes a couple of really innovative ideas to help the contractor be more efficient. One of these is an automatic feed control system that actually turns the augers on and off when the material has filled the extensions. These were paddle type switches, but you could also get a system that used sound waves to measure the amount of material. The next was a joint matcher that attached to the screed arm and was connected to a shoe that actually rode on the previous pass or other grade reference to assure precise leveling. This, of course, it the predecessor of today’s sonic controlled grade control systems. Could it be that the biggest innovation for the asphalt paver in the last 25 years is the advent of sonic controls for auger control and depth control? I mean the original machine developed by Harry Barber in the 1930’s already had slat conveyors, flow gates and a free floating screed. Today, we get caught up in the trap of who has the latest style of steering or where this toggle switch is located. Mr. Barber already did the heavy lifting for us back in the ’30s. I would challenge you to, after you have done your machine homework, do your homework on what happens after the purchase, when you have mix in the silo and trucks in front of the paver. Will you have a partner to call when something just doesn’t seem right? I’ll bet the contractor of the ’30s could get in touch with ol’ Harry if they needed him.
I guess what I’m getting at is the overthinking that we tend to do when it comes to what we need our machine to do. The innovations that we all see at the Trade Shows (albeit virtual) are awesome. Some of the recent things that I have enjoyed are telematics, hydraulic systems that make better use of horsepower and engine manufacturers that have produced that horsepower so efficiently that we can use less horsepower to do more. But let’s keep our eye on the finished product which is and always will be, placing a high quality asphalt product on the ground with minimal effort and with high precision.
I wonder what they’ll be saying about our industry in 2041?
Brian Hall, is a LeeBoy Territory Manager. He can be reached via email at email@example.com.