4 ms·

Can you explain the difference some more? I think of a bolt as a pin with threads, that gets secured with a nut on the other end. A pin has no thread and gets s

Can you explain the difference some more? I think of a bolt as a pin with threads, that gets secured with a nut on the other end. A pin has no thread and gets secured by putting another piece through a hole in the end of it. So they have different failure modes (a bolt can get its thread stripped, or vibrate the nut off) but otherwise can be used interchangeably. What's the structural difference you are referring to?

TheSpiceIsLife 7y ago
Bolts are (generally?) intended to apply force between two surfaces and not themselves act as shear resistance. Whereas a pin is (generally?) entirely a shear-force resistance component.
- dreamcompiler 7y ago
  Right. Bolts are usually weak in shear but strong in tension.Their job is to create high friction between two pieces; that friction joins the two pieces as one.
tyingq 7y ago
See this diagram: https://static.seattletimes.com/wp-content/uploads/2019/05/crane-pins-WEB-1020x602.jpg https://static.seattletimes.com/wp-content/uploads/2019/05/c... I believe the metal sleeves that the bolts go into are the pins. Edit: I probably shouldn't have said "sleeves". That has more than one meaning in this context. I'm talking about hollow pins, secured by bolts when I say "sleeves".
- appleflaxen 7y ago
  Wait... isn't that exactly what londons_explore says is wrong, and essentially the source of confusion in the first place?
  - tyingq 7y ago
    I think it's right. He seemed to be describing hollow pins with threaded holes. The pins hold the sections together, the bolts screw into, and steady the pins.
    - londons_explore 7y ago
      Correct. What I said only applies to this particular use of bolts to hold pins in place, which in turn hold the truss together.
a2tech 7y ago
Watch this video for a good breakdown of what people think happened: https://www.youtube.com/watch?v=cexN2-T6dxY&feature=youtu.be https://www.youtube.com/watch?v=cexN2-T6dxY&feature=youtu.be he has a followup video with additional pictures sent in from the scene that seems to corroborate his thoughts

TheSpiceIsLife 7y ago

Bolts are (generally?) intended to apply force between two surfaces and not themselves act as shear resistance. Whereas a pin is (generally?) entirely a shear-force resistance component.

dreamcompiler 7y ago
Right. Bolts are usually weak in shear but strong in tension.Their job is to create high friction between two pieces; that friction joins the two pieces as one.

tyingq 7y ago

See this diagram: https://static.seattletimes.com/wp-content/uploads/2019/05/crane-pins-WEB-1020x602.jpg https://static.seattletimes.com/wp-content/uploads/2019/05/c... I believe the metal sleeves that the bolts go into are the pins. Edit: I probably shouldn't have said "sleeves". That has more than one meaning in this context. I'm talking about hollow pins, secured by bolts when I say "sleeves".

appleflaxen 7y ago
Wait... isn't that exactly what londons_explore says is wrong, and essentially the source of confusion in the first place?
- tyingq 7y ago
  I think it's right. He seemed to be describing hollow pins with threaded holes. The pins hold the sections together, the bolts screw into, and steady the pins.
  - londons_explore 7y ago
    Correct. What I said only applies to this particular use of bolts to hold pins in place, which in turn hold the truss together.

a2tech 7y ago

Watch this video for a good breakdown of what people think happened: https://www.youtube.com/watch?v=cexN2-T6dxY&feature=youtu.be https://www.youtube.com/watch?v=cexN2-T6dxY&feature=youtu.be he has a followup video with additional pictures sent in from the scene that seems to corroborate his thoughts