Too many bolts removed from pylon footings

[verymadmac]

Transpower chief executive Alison Andrew says a power pylon that fell last Thursday was due to contractors removing too many nuts I guess someone read the work order wrong.

https://www.rnz.co.nz/news/national...kes-announcement-after-major-northland-outage

 

[SWComposites]

Doesn’t sound like an “engineering failure”. More like a complete failure to read and/or follow procedures.

 

[MintJulep]

Procedures matter.
Sequence matters.

⚠️Caution! Work is dangerous.  Have a safety briefing first
⚠️Caution! Wear gloves.
⚠️Caution! Wear goggles.
⚠️Caution! Wear safety shoes.
⚠️Caution! Wear a hard hat.
⚠️Caution! Read the entire procedure first.
⚠️Caution! Each of these caution statements is important!  Don't tune them out because there are so many.
⚠️Caution! Other hazards may exist and they might not be marked with ⚠️Caution! 
Step 1: Remove each bolt.
Step 2: Do something with each bolt.
⚠️Caution! The something might involve hazardous chemicals.
⚠️Caution! Read and follow the printed instructions on each chemical.
⚠️Caution! Read the MSDS for each chemical.
Step 3: Replace each bolt.
Step 4: Tighten each bolt with a power tool.
⚠️Caution! Power tools are dangerous.
⚠️Caution! Read and follow the manufacturer's instructions for the power tool.
⚠️Caution! If you are unsure of the proper use of the power tool stop and ask for training.
⚠️Caution!  Remove only one bolt at a time, or the tower might fall over.
⚠️Caution! If the wind speed is greater than 42 furlongs per fortnight do not begin this procedure.

 

[TugboatEng]

A failure to produce a procedure is an engineering failure.

The question is, was there a procedure or a failure to follow it?

 

[fel3]

My father has a degree in Petroleum Engineering, but didn't go into that line of work. After graduating in 1956, he spent the next three years in the U.S. Air Force flying bombers and cargo planes, got out to work as a general engineer with Dow Chemical, re-entered the military in the early 1960s as a part-time Army National Guard pilot, where he flew small fixed-wing recon planes and then helicopters into the early 1990s. He left engineering in the late 1960s to teach high school chemistry and sometimes physics and mathematics. Even so, he still considers himself to be first and foremost a small-e "engineer".

My father told me a story years ago about a time that he had to deliver a National Guard general from Long Beach, California, to Sacramento, California, for--of all things--a party. Even though my father had memorized the pre-flight checklist (as I understand many pilots do), he went through it on paper, line by line, each and every time he flew, as was the requirement and as fitted his cautious approach to flying. Well, this general was an impatient sort and ordered my father "to quit fooling around and get this bird in the air." My father, who does not suffer fools gladly, looked the general straight in the eye (probably with some contempt as well), and asked, "Do you want to arrive safely or do you want to die?" The general sputtered a non-response and my father completed his pre-flight checklist. When my father flew the general back to Long Beach the next day, the general didn't complain about the checklist.

============
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[waross]

This one WAS engineered:

The Lacey V. Murrow Memorial Bridge is a floating bridge in the Seattle metropolitan area of the U.S. state of Washington.
....
On November 25, 1990, while under re-construction, the original bridge sank because of a series of human errors and decisions.
....
The Washington State Department of Transportation (WSDOT) decided to use hydrodemolition (high-pressure water) to remove unwanted material (the sidewalks on the bridge deck). Water from this hydrodemolition was considered contaminated under environmental law and could not be allowed to flow into Lake Washington.[22] Engineers then analyzed the pontoons of the bridge, and realized that they were over-engineered and the water could be stored temporarily in the pontoons. The watertight doors for the pontoons were therefore removed.
....
A large storm on November 22–24 (the Thanksgiving holiday weekend),[23] filled some of the pontoons with rain and lake water. On Saturday, November 24, workers noticed that the bridge was about to sink, and started pumping out some of the pontoons; on Sunday, November 25, a 2,790-foot (850 m) section of the bridge sank, dumping the contaminated water into the lake along with tons of bridge material.
Too many bolts, too many covers.

Link to Article

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[SWComposites]

Yes, I was in Seattle when that floating bridge sank.

The Hood Canal floating bridge also sank in a Nov storm some years prior.

 

[jhardy1]

I learnt the lesson of reading the entire procedure completely before commencing the task many years ago, when I was still in high school.

I had acquired an old bicycle with a Sturmey Archer 5-speed hub, which I wanted to refurbish. I got hold of a workshop maintenance guide, and was following the steps meticulously. I was half way through stepping through the disassembly instructions, at the bottom of a page in the manual, when the whole hub exploded in my hands, showering little springs and ball bearings all over the place. I turned the page, and the first line in bold print said something to the effect of: "Be sure to apply a retaining clamp before removing the screws, as the hub is under spring load".

I gave up on trying to overhaul the Sturmey Archer hub, and fitted a 5-speed derailleur instead, which seemed to be a far simpler piece of machinery!

http://julianh72.blogspot.com

 

[JohnRBaker]

...when the whole hub exploded in my hands...

That happened to me once when we were back in Michigan on vacation and we were at my wife's sister's house. She had a fifth-wheel trailer where one of the roll-out awnings had jammed and she asked me if I could fix it for her. Now I didn't have any sort of manual or any thing like that but I figured I'd still give it a shot. Anyway, as I was loosening one of the bolts on the end of the spring-loaded awning, I went just a bit too far and the bolt popped-out and spring suddenly unwound, but not before an arm on the shaft spun around and hit the end my thumb (fortunately is was my left hand as I'm right-handed). Anyway, it split my thumb wide open and I swear that that was the most blood I had ever seen that came from ME. My wife took me to the ER and they sewed it up. They did an X-Ray and you could see that the end of my thumb was 'swagged-over' like what you'd see if you had pounded on the end of a wooden dowel.

Anyway, here's some photos of my thumb:

August 2011 (Sony DSC-H2)

August 2011 (Sony DSC-H2)

Now there was some 'good news' which come out of this accident. I'm diabetic and I have to do a glucose test every morning, which means that I have to prick my finger to get a drop of blood for the test. Well, I've never gotten 100% of the feeling back in the end of my thumb so that's where I draw my blood every morning ;-)

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without