Posted by Billy NY on February 22, 2013 at 05:05:42 from (72.226.79.200):
In Reply to: Re: Jib cranes posted by urbancase on February 21, 2013 at 19:07:42:
Unless a licensed professional engineer, checked the design, provided the calculations, details and specifications, I would question every bit of what a steel supplier says. For anyone considering the design and construction of an overhead lifting device, it has to be engineered. I realize that AISC and similar reference material may provide load tables and beam sizes, but there is missing information, which cannot be arbitrarily decided based on looks or opinion, footings, piers, columns, rigging, safety margin, all have to be designed, coordinated, checked out etc. to insure that it will safely handle the loading imposed on it, and will in fact have a safety factor.
One of the reasons I think its just a necessity is that years later, someone else may have access to what a person has previously built and will not have any details on it safe working limits, a device like this after being properly designed should also be labled stating the safe working capacity.
I say this having been in the commercial building construction industry, no steel supplier I have ever dealt with would size anything, its engineered on the building design documents, which are then used for bidding purposes, steel supplier will then after being awarded a contract, will detail shop drawings for the steel they will provide, and those shop drawings have to be approved, approved as note by the engineer of record, whom will check those drawings against the structural drawings he provided for the job.
Its's like residential housing, most carpenters or framers have a working knowledge of materials and can say what you will need say for example a roof framing job, 2x..... so many inches on center, etc. and it will work, you just can't do that with steel, given the loading and forces at work and one should never really do that in general, any structure or lifting device needs to be engineered to be safe, which means its designed for a specific purpose, with parameters of use and load limits, all components included, not just a beam that was sized as per what someone says will work, unless that person did or had someone do the necessary engineering, which to be honest, would not take long for an experienced engineer to provide.
Only reason I post this is to make sure someone does not get it in their head that steel suppliers are designers, they are not, and its highly likely no information would be typically provided given the liability it presents to the supplier, unless they have design capability and have errors and omissions insurance.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Product Review: Electronic Ignition - by Staff. Oil, for example has come a long way in the last 50 years and I don't use anything but the latest API grade available. I've heard the arguments for non-detergent oils but would never trade it for today's formulations. Paint is another, the modern acrylic enamels are great for resistance to grease and fuel stains, retaining their shine and they last forever; unlike enamels and lacquers . Still another is the alternator. No doubt using the original generator keeps the tractor pure, but for thos
... [Read Article]
Latest Ad:
Oliver 550 Diesel runs like a watch three point hitch pto engine gone threw about two hundred hours ago nice clean tractor
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
