After Effects of Power Plant Drop Tests — Repost
Originally posted March 22, 2013:
I have found that elevators have a way of equalizing personal differences when there are just two of you alone in an elevator. It is one of the few places in a Power Plant where no one is watching or listening (usually) to what is said between two parties. Once the doors open, it is difficult to convince others what has happened because there is only one other witness. Depending on your position, this can be either a good thing or a bad thing.
Soon after I became an electrician I was introduced to “Elevator Maintenance”. The Power Plant has 7 elevators. One that goes to the main office area. One that goes to the Control Room. Two for the boilers. Two for the Smoke Stacks and one that takes you to the top of the Fly Ash Hoppers in the coal yard.
The office and boiler elevators were made by Montgomery. These each had to be inspected regularly to keep them running safely. If not, then the plant ran the risk of having people stuck in the elevators for a period of time, which is never a good situation.
There were times when people were stuck in the plant elevators. I may devote an entire post to that subject at some time. Today I’m more interested in the people that inspect the elevators and the effects that elevator inspections had on them.
I didn’t think about it for a long time, but one day when I was walking by a person that I worked with at Dell, Jeremy Tupa, stopped and said, “I still get chills thinking about what you used to do at the Power Plant.” I didn’t know what he was referring to until he reminded me. He said, “When you had to drop test the elevators.” It took me a while, but I finally remembered when I had told Jeremy about drop testing the stack elevator.
Our team at Dell had gone to Six Flags Fiesta Texas in San Antonio for the day. Jeremy and I were sitting next to each other on a ride called “The Scream”. It would raise you up and then you would free-fall down and then it would quickly jerk you back up again and drop you again. That’s when I told him this wasn’t scary to me, because it was just like drop testing a stack elevator.
Oh yeah. I guess to some people that must seem kind of scary. To the people that actually perform that activity, they do things to their mind to convince themselves that everything is safe. Well. Besides that, when following all the safety precautions, it really is a safe activity (see. I’m still doing it).
When drop testing an elevator, you load the elevator with more weight than what the elevator is designed to carry. Usually by bringing a few pallets of sandblasting sand by forklift to the elevator and then piling them in the elevator until you have reached the desired weight for a drop test.
Once the elevator is weighed down, you climb on top of the elevator and manually operate the elevator using the inspection controls until you have raised it up a couple of floors. Then someone up in the penthouse releases the brake so that the elevator free falls.
Once the elevator obtains a certain speed, a tripping device located in the penthouse rolls over and locks, that causes a locking device on the elevator to engage, which sets the “dogs”. The dogs are clamps that dig into the railing that the elevator uses as sort of a track to go up and down without shaking back and forth.
Once the tripping mechanism in the penthouse is operated. it cuts the power to the elevator. Once the dogs are set, there is a loud bang and the elevator isn’t going anywhere. It comes to an instant stop.
Performing a drop test in an elevator shaft seems rather routine, and it is more trouble resetting everything and filing the track smooth again where the dogs dug in creating a notch, than it is to actually perform the drop test.
The Smoke Stack elevators are a lot more fun.
The smoke stack elevators are these Swedish made three man elevators made by a company named Alimak. They operate like a roller coaster does when it is cranking its way up the first hill. The weight limit for these elevators is much lower obviously, since they only hold 3 people.
I could usually load a few large anchors and maybe an Engineer or two in the stack elevator and run it up 50 feet or so and perform the drop test. In order to perform a drop test on a stack elevator (notice how I use the word “perform” as if this was a work of art…. well… in a way it was), you had to disengage a governor first. The governor would prevent a free-falling stack elevator from just flying to the bottom by engaging a secondary brake when the governor sensed that the elevator was moving too fast.
After installing the special governator (like Arnold Schwarzenegger) to keep the governor from engaging, using a large screwdriver or small prybar (meaning that the large screwdriver also functions as a small prybar), the brake is released allowing the elevator to free fall to the ground or well, until the elevator sensed it was moving way too fast and locked up.
Did I mention that these activities are performed while standing on top of the stack elevator? Yeah. Right out in the open. The entire elevator inspection was done standing on top of the elevator. That was how you inspected the railing and tight checked all the bolts all the way up and down the 500 foot stack elevator rail.
A large Allen Wrench with a permanent cheater bar was used to tight check the rail bolts.
One time before I was an electrician, when Diana Lucas (later Diana Brien) was pulling down on an allen bolt with the cheater bar, Jerry Day, who was with her, pressed the button to lower the elevator down to the next bolt and left Diana hanging in mid-air 100’s of feet above the ground!
Needless to say, the experience of hanging onto a large Allen wrench stuck in a bolt 100’s of feet up a smoke stack, left Diana a little scarred. Diana is a tough Power Plant Woman of the highest degree and I used to perform the elevator inspections with her. She would go up the smoke stack on the top of the elevator, but I generally did the tight check on the bolts and let her run the buttons.
This is all just a teaser to the real story behind this post…
In the fall of 1984 Ben Davis and I went to Muskogee on a major overhaul. While I was there, part of the time I lived in a trailer with a guy from Horseshoe Lake named Steve Trammell. To this day, (and Steve does read these posts) we have always referred to each other as “roomie”.
While at Muskogee Ben and I worked out of the electric shop located next to the main switchgear for Unit 6. The Muskogee electricians we worked around were, John Manning, the B Foreman, Jay Harris, Richard Moravek, David Stewart and Tiny.
All of the electricians Ben and I worked with were great Power Plant Men, and I will write a post later about our experience there. For now, I am just going to focus on one person. David Stewart. Why? Because he inspected the stack elevators at Muskogee, like I did at Sooner Plant.
I don’t know exactly how the conversation was started because I walked into it in the middle when I entered the Electric foreman’s office to eat my lunch. David was semi-arguing with the rest of the he-men in the room. The argument centered around this: David Stewart was convinced that if you were in an elevator and everything failed and it was falling to the ground, if you jumped up as hard as you could at the last moment, you would be all right.
I will pause here while you re-read the last sentence………..
While you are thinking this thought over, watch the following Pink Panther video from 1968 called, “Twinkle Twinkle Little Pink on YouTube. Especially from 4 minutes and 15 seconds to 30 seconds into the film:
At first I thought that this was an ingenious joke that David was playing on everyone in the office because everyone was falling for it (I had actually used this technique before in my own jokes). They were all trying to explain to David why it was impossible to jump up in a falling elevator at the last moment and you would be all right. The more I listened, the more I came to realize that David was convinced that this was so.
I took David aside and tried to explain to him that according to the law of gravity and acceleration that you would be falling too fast to be able to jump high enough to make any difference to your falling fate. I presented him with the formula for acceleration and showed him that if you even fell from about 50 feet, you would be crushed.
final velocity = Square root of the initial velocity squared plus 2 times acceleration times distance. With Gravity having an acceleration of 9.81 meters per second and 50 feet being just over 15 meters…
I showed him that his final velocity would be about 17 meters per second, which is equivalent to about 38 miles an hour straight into the ground. From only a 50 foot fall. It didn’t phase him. He was so certain it would work. — I understood. This was his way of coping with doing a drop test on the stack elevator. His mind had convinced him that all he had to do was jump up in the case that the elevator safeties failed.
Fast Forward 5 months. It was in April of 1985 when a man from the Swedish Elevator company would come around and do our yearly stack elevator inspection. During this inspection he told me that we needed to remove the top gear rail from the railing.
The reason was that on a stack in Minnesota, when all the safeties had failed on an elevator, it didn’t stop going up. It went all the way to the top and off the top of the railing and fell to it’s doom. By removing the top gear section, the elevator wouldn’t be able to go high enough to go over the top of the railing.
Anyway, while we were inspecting the elevator I asked him if he would be going to the Muskogee power plant after ours, and he said he would. He knew David Stewart and would most likely be working with him on the Muskogee Stack Elevators.
So, I told him the story that David really believed that he had convinced himself that he could jump up in a falling elevator at the last moment and he would survive. So I convinced the elevator inspector to tell everyone about how they need to remove the top gear section, but that it doesn’t really matter, because it is a proven fact that all you have to do is jump up in the elevator at the last moment and you will be all right.
Fast Forward another year. It was now April 1986…. The elevator inspector and I were up on the stack elevators tight checking all the bolts when I remembered about David. So I asked him, “Hey, did you ever do anything with David and jumping up in the elevator?”
He responded with, “Yeah I did! And until the moment that I had said anything I thought you were playing a joke on me, but here is what happened…. We were all sitting in the electric shop office eating lunch and I told them just like you said. When I got to the part where you could just jump up in the elevator and you would be all right, David jumped out of his chair and yelled ‘See!!! I told you!!!’ It was only then that I believed your story. Everyone in the room broke out in a roar of laughter.” — As much as I love David Stewart, I was glad that the joke was performed with perfect precision.
Now for the clincher…. — Oh. You thought that was it? So, let me explain to you one thing about drop testing the stack elevator… The elevator doesn’t go up and down like regular elevators with cables and rails and rollers. It uses one gear on a central rail that has notches to fit the gear.
The gear is heavy duty as well as the rail. You can count on it not breaking. The gear was on a shaft that was tied to the braking mechanism, the governor and the motor through a gearbox. The ultimate clincher is this… The gear… The only thing holding the entire elevator up and the only thing tied to any kind of a brake had one pin in it that kept it from rotating on the shaft. One pin. In mechanical terms, this is called a Key:
Everything else on the stack elevator can fail and the elevator will not fall, but if this pin were to fail…. the elevator would free fall to the ground. Thinking back, I must have explained this to Jeremy Tupa, my coworker at Dell back in 2004 when we worked together. It made such an impact on him that I would drop test an elevator that was completely held up by only this one pin. This is the weakest link in the chain.
I know that every now and then I wake up either from a claustrophobic fit because Curtis Love just shut my air off (see the Post: Power Plant Safety as Interpreted by Curtis Love) or while I’m taking a flying leap off of the stack elevator. If only I could have the confidence that David had. If only I could believe that jumping up at the last moment would save me.
Actually, I can picture jumping up and a hand reaching down to grab me and pulling me up… only it pulls me on up to heaven. That’s when I’ll know the truth. David was right. Just jump up as hard as you can. Jump and know that you will be safe. God will catch you.