Cracks in Bridge Crane Rail

8 comments

Rate

Anonymous Poster #1	Cracks in Bridge Crane Rail 02/28/2013 8:09 AM
	There is a 33 Metric Tonne Coker Handling Bucket Crane installed in the Delayed Coker Unit for transfer of pet coke from collection pit to conveyors. During operation for the last one year, we have observed major cracks with big gaps along the plane perpendicular to the linear rail axis. Most of the cracks are near to the weld joints between the adjoining rails. What is the reason for such failure and solutions for this sort of problem?
	Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

These comments received enough positive votes to make them "good answers".

lyn Guru Join Date: Oct 2008 Posts: 42355 Good Answers: 1693	#1 Re: Cracks in Bridge Crane Rail 02/28/2013 8:17 AM
	Reasons: Poor workmanship; overloading; lack of maintenance; improper welding or PWHT. Solution: Hire a mechanical contractor who works on cranes and PAY THEM to fix it.
	Reply Good Answer (Score 3)

MJCronin Power-User Join Date: Oct 2009 Location: Central Midwest Posts: 455 Good Answers: 38	#6 In reply to #1 Re: Cracks in Bridge Crane Rail 02/28/2013 1:56 PM
	banu... How old is the Crane and when was the last inspection ? (I expect that your answer will be: I don't know,.... the plant was purchased from someone else a couple of years ago, and all records were discarded...... Oh ..I am 22 years old and this is my first job ) In the USA, crane inspection is a serious business....is performed on a periodic inspection basis, by a certifed independent contractor who must submit results to the state/federal government and retain records forever.... (See 29 CFR part 1919) also see: www.craneinspection.com What country are you in ???? __________________ We have met the enemy....and he is us. POGO
	Reply

passingtongreen Guru Join Date: Aug 2009 Location: Glen Mills, PA. Posts: 2385 Good Answers: 114	#2 Re: Cracks in Bridge Crane Rail 02/28/2013 8:34 AM
	This requires an expert on the spot to ask many questions, how soon did the cracks appear after installation? how frequently does the bucket go by? how long has it been in operation? How were the welds made? and more, and I am no expert on this type of question. __________________ In a time of universal deceit, telling the truth is a revolutionary act. George Orwell
	Reply

nick name Guru Join Date: Mar 2007 Location: City of Light Posts: 3943 Good Answers: 183	#3 Re: Cracks in Bridge Crane Rail 02/28/2013 1:16 PM
	It would be good to have some pictures. This is a fatigue consequence and fatigue us due to too high loads and stress concentration. It could be possible that the welds were not made in a professional way. There are many possible reasons Pictures will permit a better understanding and a more precise judgement.
	Reply

jack of all trades Guru Join Date: Sep 2006 Location: Auckland, New Zealand Posts: 8777 Good Answers: 376	#4 Re: Cracks in Bridge Crane Rail 02/28/2013 1:16 PM
	As Lyn said above, with the added comment GET SOMEONE COMPETANT IN CRANE REPAIR IN IMMEDIATELY TO ASSESS AND REPAIR THE DAMAGE! It goes without saying that it would be wise to stop using the crane until you can get it inspected and repaired or replaced with something more suitable to your application. Just because it has run fine for a year doesn't mean it won't fail catastrophically tomorrow and kill someone. _{Jack - Safety first} __________________ jack of all trades
	Reply

lyn Guru Join Date: Oct 2008 Posts: 42355 Good Answers: 1693	#5 In reply to #4 Re: Cracks in Bridge Crane Rail 02/28/2013 1:44 PM
	Oh, heck. What's a few, "major cracks with big gaps along the plane perpendicular to the linear rail axis" among friends? Life is cheap in Anon Land.
	Reply

jack of all trades Guru Join Date: Sep 2006 Location: Auckland, New Zealand Posts: 8777 Good Answers: 376	#7 In reply to #5 Re: Cracks in Bridge Crane Rail 02/28/2013 4:21 PM
	You would think they would come up with a safer way to handle Coke. I wonder how Pepsi do it? __________________ jack of all trades
	Reply Off Topic (Score 5)

TerraMan Power-User Join Date: Nov 2011 Posts: 473 Good Answers: 13	#8 Re: Cracks in Bridge Crane Rail 02/28/2013 10:17 PM
	As Nick pointed out it's most likely fatigue cracking. The culprit is typically improper welding and improper support under the rail. Crane rails are made from high carbon steels and require very specific welding procedures. Google "crane rail welding" to learn about it then higher a professional to deal with it. Good luck!
	Reply

These comments received enough positive votes to make them "good answers".

Copy to Clipboard

	Got Something to Say?
	Ask a Question Start a Discussion

	Aerospace
	BioMech & BioMed
	Chemical & Material Science
	Civil Engineering
	Communications & Electronics
	Education and Engineering Careers
	Electrical Engineering
	General Discussion
	Instrumentation
	Manufacturing
	Mechanical Engineering
	New Technologies & Research
	Software & Programming
	Sustainable Engineering
	Transportation

	Site Directories
	Forum Directory Blog Directory User Group Directory RSS Feeds CR4 Rules of Conduct CR4 FAQ Site Glossary Who's Online (74 right now) Show Members