Elevator Mechanic Practice Exam

You are installing spring buffers on a 200fpm car, what is the minimum buffer stroke?

1. 2 ½ inch

2. 4 inch

3. 6 inch

4. 8 inch

The correct answer is: 4 inch

In elevator systems, the buffer stroke is critical for providing a safe and effective way to absorb the energy of a descending elevator car in case of an emergency or malfunction. For a car traveling at a speed of 200 feet per minute (fpm), industry standards recommend a specific minimum buffer stroke to ensure adequate safety and performance. A buffer stroke of 4 inches is suitable for a 200 fpm car because it provides enough space for the buffer to effectively absorb the kinetic energy of the car, preventing potential damage to the car and the shaft. This stroke length is consistent with safety guidelines that balance performance and safety, which is essential for passenger elevators traveling at moderate speeds. Increasing the buffer stroke beyond this minimum may not be necessary for a car operating at this speed, but it is crucial to meet or exceed the minimum requirement to maintain safety standards in elevator design and installation.