Elevator Design

I agree Nick. I'm getting very tired of these foolish amateurs that think they can replace education and a respect of sound engineering practice with answers from an anonymous blog. If these fools were only putting themselves at risk I'd be more forgiving.

Dear Sir

Dont think others as fools like You. If you dont want to answer ,simply leave the question.This is the place for experts and as well as amateures. without these amateures, you will not be experts...

I explained my problms.Try to understand others.DOnt under estimate others...

Well your two replies are a little more informative but still insufficient for me to take you seriously. First, you should have noticed when you signed in here to CR4 that you did not have to meet any financial or educational qualification to post anything here at all. So nobody here knows if you understand the fundamentals of basic Newtonian mechanics, let alone which parts pertain to your engineering problem of an elevator. So all respect for knowledge and ability one possess must be obtained here by what you write here not by any academic degree, nepotism, or job title. So far you have not demonstrated any knowledge at all on the operation, safety or design concerns of an elevator. Right now I'm not even sure you understand what percentage of the load on an elevator cable is the static load of the occupants, let alone all of the other loads that repeatedly happen to this constantly flexed cable.

You will be swamped by "engineers" from third world countries who think they can do anything with the knowledge obtained from "real" engineers. Best to just ignore such questions. That's what I do.

I seriously suggest that you call an elevator company who is certified in your area.

Please don't tell me you ARE an elevator company. Your first two questions here were amateurish. This one is dangerous, and unethical, if you call yourself an engineer.

Of course there are formulas and design calculations. (Good grief, what kind of question is that, anyway?) But we are not going to tell you what they are.

Pissed myself laughing at that pic!! Questions like this never cease to amaze me.

Dear Friends!

Why all of You getting angry with my questions? I am not going to erect a lift with your answers. But try to understand my problem.

I am working in a Power plant and we propose a retrofitting of one passenger cum freight lift. One lift erection company has got the above work on turn key process. The company submitted a design data for my approval. I want to verify whether the proposed data is correct or not.(the real problem is that the company is not knowing the design details from which they arrive the rope size and motor capacity) So I need the help from all of you. If you can,suggest otherwise simply leave it.

I dont have any idea of killing any body..

Aravarasan, you did not explain this in your original question. There was no way for us to know your intent because you did not provide any background information at all. This is why we responded the way we did.

If you look through this forum you'll see many questiosn asked by anoymous posters that are vague with no information to go on. It gets frustrating especially to the members that have been here for a long time and keep seeing the same thing over and over.

It's good that you explained your situation and now hopefully you will get some meaningfull answers. In the future, you should always clearly explain what you need and provide background information.

Regards

Thanks Mr.TerraMAn...I pray for getting suitable guidelines from the experts..

Aravarasan, I can offer you this. When my company accepts a contract we are responsible for all engineering and approvals. Our clients approve our designs in concept only to ensure we meet their functionality requirements. My opinion is that you, the client, should not be responsible for approving your suppliers engineering calculations. That is their job and all liability / responsibility rests with them.

Regards

ARAVARASAN,

You have clearly and convincingly demonstrated that you are not qualified to be involved, let alone, apporve this project.

Hire a qualified, local engineer to review and approve the data.

We are simply telling the you truth.

So, now we know that a company that is not capable of completing the design is asking for design approval from the Client? If that happened to me I would give the company the expletives it deserves, pick up the phone, and find someone that is capable of completing the design.

I mean, has your indemnity insurance company been involved at all yet?

Good grief, Maggie!

This is like the blind leading the blind. I wonder who's going to get the shaft????

_{Please, no applause.}

I had to do a cargo lift in our main office for moving lab samples and files (stored in banker boxes).

Our Safety Director was in charge of it, which after they could not find an adequate design it was passed to me.

I have design lifts and dumpers before, But since there are sales people are stationed at the office. I knew those bastards were going to ride it.

I was not even going to mess with the design, what I did was an easy googled and came up with this within minutes.

perfect, now I got the safety director working on the local ordinances.

Now as far as your comment:

I dont have any idea of killing any body..

Nobody intends on hurting anybody, but Ignorance does kills.

If the company is not able to justify what is one of the most important elements of the system then TRY TO FIND A SUPPLYER who has the skills and an indpendent true specialist to check the data of the proposal as well commercially as technically.

I was involved in the design of load lifting systems for building sites which are as well for goods as for human beings and can tell you that your solution is not the equation for a cable dimension but a true professional supplyer.

We are having old lift having spec as below:

Capacity: 1360 Kgs/20 Persons

Distance Travel : 0 to 52 Mtr (G+6 landings)

Speed: 1.5 m/s

Power: 30HP DC Motor(supplied from a DC Generator which was driven by a AC Motor)

Rope Size: 6 Falls 6X19 const 16mm dia

Now the company proposed new lift as follows in the same shaft,car and counterweight rails.

Capacity: 1360 Kgs/20 Persons

Distance Travel : 0 to 52 Mtr (G+6 landings)

Speed: 1.5 m/s

Power: 30HP AC Motor with VVVF drive,Fully collective control

Rope Size: 5 Falls 6X19 const 13mm dia

From the above,I can see the rope size and dia were reduced and motor capacity semms to be high and more energy consumed. So I need a coorect solution for the design approval. pls help.

You just do not understand the problem you propose here. The problem is not a Physics, Material Science, or Mechanical Engineering problem. The problem is a business and liability problem. You have a contractor that is proposing to replace a system that differs from the existing system. Technology changes with time. Somebody (this firm, your boss, or your own apprehensions upon seeing the equipment) has prompted you to review this design when you are clearly not qualified to do an evaluation. You cannot foist your responsibility to solve your problem on us. The only thing you should do is admit your limitations and neither approve or reject this design. If your employment expertise is supposed to include elevator expertise, offer to resign too. If an outside design review is insisted by your company then hire a certified consultant to review this design.

Desperation can be a cruel mistress ARAVARASAN.

Quit wasting time and hire a certified elevator technician or engineer.

I can ONLY repeat what I already wrote and ALL other suggested: if the company cannot justify the design they propose ask for a company which can do that. You are NOT the right person to accept or reject the project since you do not have the knowledge to do it. My second recommendation is to hire a consultant - specialized in lifting - for the analysis of the presented project.

To your information you want to compare 2 solutions which are of different technologies justified by the technical evolution and you do not have the skills to do it. The cable problem is not a true problem since it depends on the loading capability of chosen cable and only as a further comment a slimmer cable can better accept the frequent bendings in function and give a longer MTBM.

What is your position in the company ?