Ask the Engineer- 1/7/18: How are amusement parks kept during off season? How are roller coasters/large attractions stored/preserved during winter?
This question came from a user on Quora. My original response to the question can be found from this link.
The offseason is actually the busiest time of the year for maintenance personnel at any park. Not only are they tending to the park grounds, fixing infrastructure, and even constructing new additions, but they are also in charge of making sure that the current rides at the park are running in the best condition that they can be.
After the park closes on the final day of the operating season, the operations and park services teams do their final sweep of the grounds. The paths and ride queues are cleaned for the final time, and all garbage is disposed of. All items placed in the park by these departments are collected and put into storage for the winter. For operations, this includes ride water coolers, seats for operators, fire extinguishers, rain coats, and emergency equipment. Park services will remove benches, garbage cans, and other cleaning equipment from the grounds.
Maintenance then takes over and begins dismantling ride vehicles, and certain electronics/motors that will be stored and inspected during the offseason. For any type of ride in a certain park, the track, support structure, main housings, etc. will remain standing until opening procedures begin again.
The following video posted a couple of years ago by Kings Island shows off a lot of the procedures performed by the maintenance department to these rides:
From the beginning of the video to the 1:15 mark, you can see the process of removing vehicles from the ride tracks. Components like brake fins and vehicle covers may removed so that they do not get damaged while moving cars around. At that point, any hitching device that links cars together is unfastened, freeing each individual car. Then car-by-car, a crane lifts them off of the tracks onto a frame in which a forklift can move them to their designated storage bay.
Then begins the tear down process. This portion is shown up until 2:07. All seats, restraint devices, wheel assemblies, other moving parts, and hoods or paneling that gives the cars their shape are removed and cataloged for inspection. All that remains of the vehicle is the bare chassis, which is subject to NDT (non-destructive testing).
Some components are replaced with accordance to manufacturer specifications, which can be given through the ride manual via time in years, number of cycles, or running hours. These components are just replaced rather than inspected. Some of the parts that I am referring to here are wheels, bearings, springs, nuts, bolts, upholstery, and others.
Others are inspected not based by time of usage, but by their dimensions. In this case, the components are larger and more structural, such as spindles, shafts, hitches, and the frame itself. Much like manufacturers provide standards for other parts, they also give dimensions and tolerances for other critical components.
After undergoing a spray wash to clean away old lubricants or oils, parts are analyzed to see if they fall within the manufacturer's range. For example, a certain shaft may require a length of 24 inches, plus or minus a fraction of an inch. If the part falls outside of this range, it will need replacement. Along with dimension analysis, the steel and materials are inspected with ultraviolet lighting, or magnetic particle testing to look for any possible cracks, stress fractures, or bad weld joints. At times, a park needs to make the decision of buying a new frame or train entirely if the testing fails.
After it has been determined which components are good to use for another season, or need replacement, maintenance technicians then rebuild the cars back to operational condition. Along with new items, upholstery (seating/padding) and painting touchups may occur. Certain parks also polish or wax their vehicle's covers to make them shine brighter and repel moisture.
Once the weather thaws, track walks and inspections happen to see the integrity of the ride structures, and the ride vehicles are rebuilt on the track. Articles regarding track inspections and safety testing/inspections will be the subject of future articles.
For now, feel free to direct any more questions my way, or view the original Quora answer for more info. Thanks for reading.