anyone done lift plans? 7

[delagina]

I've been asked to do this. Can someone give sample drawings or a guide how to do this.
Before I turn this down, I want to make sure I really can't do this.

 

[delagina]

this is for pipeline and small equipments. a go-by drawing would be good.

 

[TehMightyEngineer]

Have you any experience with rigging/lifting or is entirely uncharted territory for you? If the latter then I'd steer clear.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[SlideRuleEra]

Make sketches, with dimensions and weights, of the items to be lifted then post them here. There are no generic plans on how to do this. Each lift has its own challenges that have to be addressed. A big factor is the type and lifting capacity of equipment available to make the lift. Also specify the conditions of the lift, e.g. inside a building, from a barge, lift to high elevation, unload a railcar or truck, etc.

Otherwise, take TME's advice.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[TehMightyEngineer]

To expand on my comment; some of the biggest issues are understanding how stable (or unstable) something can be when lifted. In addition, being able to plan each stage of the lift takes experience. Figuring out loads and forces is fairly typical but the trick is knowing all the design checks, impact factors, accidental loadings, and required OSHA (or other jurisdiction's) safety factors that are required. Finally, as you noted, getting all this information onto a document that communicates you intent is another experience area. I'm sure I'm leaving out a few other things as well.

When you add this all up, combine it with a low redundancy situation, and add to that the consequences of failure and the likelihood of litigation should it go south, then you can see why I wouldn't attempt this in your shoes.

All that said, this is definitely just a situation of getting experience with it assuming you're a competent structural engineer. Perhaps you can hire an outside consultant to do the design for you where you review and approve it? If you can get that experience then it's definitely not the most complicated structural engineering task out there and quite rewarding.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[andriver]

Heavy Lifts (50 ton-8000 ton)are my bread and butter. Mighty Engineer brings up solid points, stability being an especially important/overlooked one. If you provide more info, object/weight/lifting attachments/lifting equipment etc I could add more detail. I won't post any of my lift drawings as those are proprietary, but I will do my best to address specific questions. I have attached a solid reference though to get your feet wet.

 

[SlideRuleEra]

TME and andriver bring up good point. From the question, it is not clear if the lift plan is for a specification to establish guidelines for a lift. (Say, what should be considered to make a large lift?)

or, the opposite

Say, a Contractor has a modest size and model crawler crane with specific capabilities and limitations. How to make a plan for that specific machine to make a heavy lift?

I'm addressing the latter. If that is not the case, disregard my previous post.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[gravityandinertia]

That's a cool document. It's interesting that they review trigonometry and centers of gravity. While I understand the need to remind people these are important, I certainly wouldn't want someone designing a lifting scenario if they didn't already have a masterful understanding of those topics already!

 

[StrucPatholgst]

I used to do rigging plans for crane work, for loads in the 50-150 ton range. Rigging plans have to be thorough. This isn't a hand sketch, one-page deal, and not a task you learn in a chat room.

 

[KootK]

This department of energy doc is a decent reference as well: Link

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[delagina]

@andriver, TME, Slide,

what are the sensible questions I should ask the client?
my boss wants me to come up with questions.
do you use any software specific for rigging?

we are bidding for this project so I need to come up with estimated hours.
how many hours it takes to do the lifting plan drawing of this site (attached)?
Do I need just 1 drawing for this?
It's just a 30" pipe with a valve and a few small equipments.


My main objective now is to come up with "sensible" estimated hours to do the lifting plan drawing of this site.

I definitely need the help of experienced rigging planner later if we get the project.

thanks,

 

[andriver]

You need to understand the scope of this lift plan, some questions:
- Are you to provide just a rigging arrangement drawing, with loads and the rigging called out? Or will they require you to specify the equipment, crane/radius/configuration/ground bearing pressure/mats etc?
- Does the object you are lifting have lifting points, or will you have to design some? (If it is just a pipe you could probably just basket or choker hitch around it and avoid designing any).
- Will a weight and CG be provided or will you need to calculate this?
- Are there any obstructions for which you need to design specific rigging or equipment arrangements/sequence to avoid?
- What equipment do they have to perform the lift?
- What deliverables are they expecting? Rigging drawing, crane arrangement drawing, calcs?

As far as software, I only use RISA or SACS (an offshore structural analysis software) in order to determine COG/weights/ and to check the structure for lifting forces.

 

[SlideRuleEra]

I see a "power pole" on the plan. Ask about any nearby overhead wires, energized or not, at the time of the lift. Do the same for any buried electrical cables/duct bank, utility piping, or power pole guywires.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[TehMightyEngineer]

andriver & SRE have the key points outlined. A few additional thoughts:

This does look on the simple side so definitely a good place to start, especially with your note to bring someone else on for this project to get the details ironed out.

- It appears the pipe is 45°s from the ground up to the valve so if you pick adjacent to the valve you should have a CG below the pick points and this will keep it from spinning if you go with a basket and choker hitch.
- If possible, design this to be lifted with an excavator that the contractor has on hand. Cranes are expensive, excavators are not.
- You will want to verify that the pipe has sufficient strength for this. Offhand I suspect it will but depending on your valve weight and wall thickness some lifting arrangements might deform the pipe.
- If you draw this up in Autocad (or similar) you can get the CG location from a LISP routine or a MASSPROP command.
- Establishing the scope early and paying careful attention to the verbage used on the drawings will be key to ensure you're not taking liability that should be borne by the contractor. Means and methods and all that good stuff.
- Draw your lift out at key stages to ensure you have anticipated all the steps in your calculations and so that the contractor lifts as you intended or can raise issues if they see a problem with it during their review.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[delagina]

for drafting or even calculation do I need softwares likes these?
this looks like they have built-in cranes, radius reqt, etc...

http://www.kranxpert.com/

http://www.3dliftplan.com/Info/InfoHome.aspx

 

[TehMightyEngineer]

I'd only get specialized software if this was something you are planning to do as a major focus of the company. While I don't do lifts over 50 tons I still have done a lot of lifting designs in my earlier career for various mills and now with precast pieces. I still only use RISA & AutoCAD and hand calculations for them. They're all usually so custom and variable that I want to make sure I have a good idea of the calculations involved rather than using a black box.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[delagina]

Shouldn't lift plans show crane and other equipments and all attachments?
Are there blocks available in autocad for that? We currently don't have this.

 

[dhengr]

Delagina:
I would question the client, their experience and capabilities, and their motives when they need to hire out the lift planing for this kind of job. Given a total lack of experience on this type of job, are they looking to you to be their insurer of last resort; and when something goes wrong you’ll be hung out to dry, all for a few thousand dollars of fees, on a project where your own company seems totally lacking in experience also. Your boss doesn’t know, so he assigns the job to you, and then offers you absolutely no guidance. Then your solution is to buy a $5000 computer program to do a $3000 job. While no lifting job is insignificant when people could be hurt and equipment could be damaged if things were done wrong, this looks like a pretty typical maintenance job (a valve replacement) for an experienced pipeline contractor. As important as anything might be some thought about the idea that you kinda need two adjacent temp. work stations, one for positioning and final prep. of the new valve pipe section when delivered, and a second to set the old valve section down on so you are not wasting a bunch of time maneuvering the two, while the line is shut down. Is the lifting to be done from within or outside the fence? Site soil conditions?

We should all aspire to grow and learn in our profession and capabilities, and reach for new challenges. Some learning can most certainly be done, today, by questions and participation on an engineering forum. You quickly learn which guys/gals on the forum have the experience and shot straight, and which ones you should probably take with a grain of salt. Some learning is better done with eye-to-eye mentoring and experience transfer, and it doesn’t sound like you are going to get that from your boss. So, if he wants to get into that business, he should find you some help to even put this bid together, so you all gain the experience without getting hurt, financially or otherwise.

 

[andriver]

We don't use any specific lift plan software, we draft our own blocks of equipment and use those for clash, crane arrangement drawings in autoCAD. We use structural software to analyze the structure. You really don't need to get that fancy, and would only need to put that effort in only if you are doing many lift plans. For most lifts, a simple diagram to scale of the crane boom will get you what you need 90% of the time. I think as far as bidding a job, you have the questions you need to ask here, worrying about autoCAD blocks before you even know what equipment will be used is getting ahead of yourself.

Off the top of my head you want:
Rigging arrangement drawing:
- Show in detail the rigging arrangement - slings (length and diameter) ,shackles (brand and capacity), spreader bar (lengths and capacity), lifting attachment points, blocks etc. Also you should call out if there is any basket or choker hitches
- The drawing should show the center of gravity referenced from a point that is easy to pull tape from
- Specs on sling type (ie X.X.I.P), and whether sling lengths may be substituted (ie I have a 20' sling but you called out a 30' sling)
- Some firms place a chart showing capacity of slings, and utilized capacity on their rigging chart. Don't forget about your D/d reduction if you are choking or basket hitch around anything.
- Also, a minimum of 5.0 FOS for the ultimate breaking strength should be used in rigging.
Crane/Equipment Arrangement Drawing.
- Layout/plan view showing location of crane/cranes, radius, any crane mats necessary, steps (such as tracking forward or rotating 90 deg etc)
- Identify any potential clashes, you need to also make sure you have enough height to lift what you want with the rigging you specified.
- Chart that shows capacity of crane, total lifted load (rigging, weight of item etc), crane radius, crane configuration (ie 250' boom, 300 ton counterweight, luffing, etc), track pressures if relevant, and crane deductions (weight of wire rope, block, etc)
Lift aid drawings
- If you have to design padeyes or trunnions or something, a structural drawing showing all the necessary componenets (dimensions, plate type/thickness, capacity, BTH identification plate)

I know I am missing something, but this should give you a template of what you should deliver to the client.

 

[delagina]

The drawing I attached is for 1 site. We have like 30 of these per project.
I guess my boss wants to add this type of work to projects we can do.