Limited Thinking Results In Limited Solutions
Of course a prep-free tunnel can be designed and installed with today's technology. The problem with the nay-sayers is their limited thinking confined within a familiar frame of reference.
The average tunnel ranges between 90-130 feet of conveyor. Look at the average equipment package included inside the tunnels and you will likely see stuff jammed up with very tight tolerances, little drip-space and little real dwell-time. Yet, since the equipment supplier said the system can do 100-120 cars-per-hour, the operator runs the conveyor far too fast to achieve the desired result. Although the operator is using plenty of "
soap", the cascade-effect of too little dwell-time further compressed with a too-fast conveyor... and cars are not as clean as they should be and wetter than they need to be upon exiting, due to the too short drip-space. The bottom-line: Far too many carwashes run their systems too fast to reach optimum efficacy. If I see a carwash with a line of cars waiting to be processed, and gaps in their ideal conveyor spacing, it is a clear indication that management is inattentive.
Another area for scrutiny: Having 20-feet of conveyor loading inside the building... instead of outside the building. Too many operators have the conveyor start right inside the door, wasting 20+ feet of building for parking while loading... that should be devoted to cleaning & drying.
Instead, I frequently suggest a 40-20-40 floor plan that segregates 40% dwell & washing space from 20% rinse & sealing space, and 40% drip-space & drying. Then, set the conveyor speed at an optimum to complete the process acceptably. Cleaning chemicals, rinsing agents, premium sealer products are job-balanced to render a clean, dry shiny car within the optimum performance speed. The benchmark is an acceptably clean & dry vehicle. Throttling the conveyor speed often results in a foolish compromise.