To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.technicOpen lugnet.technic in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Technic / 8021
8020  |  8022
Subject: 
Re: The Big Lift
Newsgroups: 
lugnet.technic
Date: 
Mon, 19 Aug 2002 01:16:27 GMT
Viewed: 
2814 times
  
Great Crane! I am so jealous of the amount of bricks and plates you guys have.

In lugnet.technic, Thomas Avery writes:
In lugnet.technic, Roy Nelson writes:
How do you tell when the crane is about to fail?

You have to look very closely at the crane, and pay careful attention to it
as the lift progresses.

I first take the slack out of the lifting lines, and then reel in the line
in short bursts. Slowly, but gently, the object will begin to lift. When the
crane "failed", the load seemed like it was just about to lift off the
ground, but it wouldn't happen. I then noticed that the main structure of
the crane was starting to creep forward and downward, indicating that
something in the base was starting to give.

That's what I keep finding. The hardest part of the crane to get strong
enough tends to be the base/outriggers/crawler frames. The boom is easily
strong enough.

You can add counterweights, but that just reverses the problem, the frame
then has to support the counterweight without any load. Superlift is the
obvious answer for crawlers and big truck cranes, but that just means more
pieces are needed.

Regards
Gordon



Message has 1 Reply:
  Re: The Big Lift
 
(...) Depends on construction technique. For my small mobile crane the construction I used meant the boom was significantly weaker than normal (bending-wise), and in fact when it failed, even though I was watching closely, it went so fast I was (...) (22 years ago, 19-Aug-02, to lugnet.technic)

Message is in Reply To:
  Re: The Big Lift
 
(...) You have to look very closely at the crane, and pay careful attention to it as the lift progresses. I first take the slack out of the lifting lines, and then reel in the line in short bursts. Slowly, but gently, the object will begin to lift. (...) (22 years ago, 17-Aug-02, to lugnet.technic)

5 Messages in This Thread:

Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR