Short conveyor washes or mini-tunnels have been around for decades, mainly in auto dealerships and gas sites.
A mini-tunnel is an alternative to having multiple in-bays on a site because the incremental cost to increase in-bay capacity is greater than a conveyor.
The mini-tunnel has comparative advantages.
Foam brushes spin at a much faster rate than soft-cloth, so more horsepower is applied, accomplishing more work. A five-touch system with fully articulating wrap-around brushes, top brush and side/rockers covers all surfaces and high-pressure wheels penetrate rims. You also have an the full complement of revenue boosting extra services; wheel brightener, rust inhibitor, tri-foam, Rain-X or Double Bond, clear-coat, spot free rinse with mirror attachments and automated tire shine.
Higher volume in-bays like Autec, Broadway, Istobal, etc. basically place a four or five touch system on wheels which means having between a 50’ and 60’ long building.
The best I have been able to accomplish during my career is Bubble Wash Express, Manhattan, Kansas. I mentioned it earlier.
The wash has a 55’ long conveyor in a 40’ long building. It has a 5-touch system with high-pressure wheels and “no-drip space” method of drying. The wash is operated without an attendant and has reached a 32 car hour. By 32 car hour, I am referring to highest recorded hourly volume not average volume. This wash generates more revenue than most 5 + 1’s.
Stretch the building to 50’ and put in a wheel boss and 45 cars an hour or more is very doable.
A mini-tunnel can also be designed with a moving platform instead of a conveyor. The belt is easier for customers to self-load vehicles and would permit more rim/tire combinations like dual wheel vehicles.
Because of the mini-tunnel’s comparative advantages, I believe we will see a lot more innovation in the in-bay equipment segment in the future.