Felix Kloman, president of Risk Planning Group and insurance consultant to the ski area industry, recently stated in an article in this magazine, “The cost of insurance is primarily a reflection of the losses which ski areas have been forced to bear. To a certain extent the industry itself can be blamed for failing to recognize that it now has a national, rather than a regional or state, stature . . . much greater attention will have to be paid to safety and loss control.” Is this a feasible alternative? Is it indeed possible to stop losses before they occur? The answer is a resounding — YES! It is possible to stop many of the mechanical breakages which result in the staggering lawsuits. These can be largely prevented through a program of preventive maintenance, inspection, and nondestructive testing (NDT). Find the parts that are about to break and replace them before they do!
NDT and “Failure-Free” Operations
This relatively new problem of the “unpredictable” failure (and its consequences) has already been solved by other industries in similar situations. Many industries can live with unexpected failures — parts wear out, machinery breaks, parts are replaced in a normal maintenance routine. It is only when unexpected failures result in catastrophic losses that industries invest heavily in inspection, testing, and preventive maintenance.
In the space program, the nuclear submarine, and the commercial airliner, a single “unpredictable” failure can result in losses of millions of dollars. In papermills and powerplants, where equipment runs twenty-four hours a day, a single unexpected shutdown can cost the plant hundreds of thousands of dollars in production losses. A failure in the amusement industry will result in lawsuits and lack of public confidence. All of these activities, from the space program to the amusement park, have one thing in common — all rely heavily on nondestructive testing (NDT). NDT has been found to be the single most effective means of determining WHAT equipment should be replaced — WHEN!
Now this same technology is available to the ski area industry. New NDT equipment has been developed, new techniques applied, and new training programs formulated to produce highly qualified NDT technicians for the ski area. Modern NDT now offers ski area owners and stockholders the same kind of failure prevention as is found in the space program and the nuclear powerplant.
NDT TECHNIQUES
There are four common methods of NDT: Ultrasonic Testing, Radiographic Testing, Magnetic-Particle Testing, and Liquid Penetrant Testing. Together these combine to provide a spectrum of capability for detection of failures in ski area equipment before they happen.
Ultrasonic Testing converts an electrical signal to a physical vibration and transmits it into the material. The signal is echoed and returned. Using ultrasonics it is possible to detect pitting, corrosion, and thickness wear in chairs, gondolas, and towers; fatigue and cracking in bearing journals and rotating shafts; and defects in new or old welds such as cracks, slag pockets and incomplete fusion.
Radiographic Testing uses X-ray and isotope sources to examine materials to find internal flaws and discontinuities. X-rays are passed through the material onto a film. A “shadow picture” is shown as the material absorbs the radiation. Abscesses, cracks, sand, porosity, or other weaknesses are readily apparent to the trained NDT technician.
Liquid Penetrant Testing provides fast, accurate indications of future failures by identifying small surface discontinuities which will result in breakage under load. The liquid penetrant is applied to the material and the liquid seeps into the surface flaws. When a developing chemical is applied, the defects become visible to the technician.
Magnetic-Particle Testing is a simple method of finding cracks and fatigue in large areas by passing an electric current through the material and analyzing the resultant magnetic fields induced by fatigued areas in the part. A magnetic leakage field caused by discontinuities will draw fine ferromagnetic particles over the surface to show the location, shape, and size of the flaw. Forgings, cast parts, gears, shafts, welds, and most auxiliary lift apparatus can be inspected quickly and economically in this manner.
NDT of Ski Lift Equipment
Using a combination of the above four techniques, a skilled technician can test a large number of the critical parts in the ski area without removal or disassembly. The qualified technician uses the right inspection method for the right part. He inspects only those parts which are subject to failure. Lift drive and counter balance systems, cables, chairs, critical tower components, brakes, sheaves, and hanger arms — all of these vital parts can be quickly and thoroughly tested to find indications of fatigue and prevent the imminent failures. For years, the paper industry, powerplants, submarines, and the space program have used priority inspection systems to concentrate NDT in critical areas to insure the maximum safety at the minimum cost. Similarly, the NDT technician and the ski area operator can jointly determine which of the parts in his equipment fit into the following classes and when and how frequently they should be tested:
Class I — If a failure occurred in a component part of the system, it would result in equipment damage, bodily injury and/or loss of life to public or operating personnel.
Class II — If a failure occurred in a component part
