Estimating Structural &Piping Work Manhours

Hi Mohd

Your sole source for productivity in any project has to be the BoQ or cost plan.

The estimator will have split the unit prices into Labour Plant and Materials.

You must study the Labour and Plant content to ascertain the productivity for that specific project.

Best regards

Mike Testro

i find it iirregular that a fresh graduate is tasked with estimating manhours for offshore hook up and commissioning projects. Manhour Estimation needs a degree of experience and understaning of the tasks, operations involved, manpower and equipment, crew size and durations.

The estimated manhours for structural and piping should already be available by the estimating department, or by the department who prepared the technical or commercial proposals in securing the contract. Inquire from them.

Thanks for the comments. So, that's mean, planning is all about base on experiences only?..no specific reference are applicable?

I'm not really in estimating on whole projects. I had been assigned to understand how to estimate manhours by using standard norm. One of their suggestion is by using "Spon's Fabrication Norm for Offshore Structures" book for starting points.

Let say I have an Isometric drawing of 12 m pipe of 24" schedule 80 with 10 weld joint. How do you guys really estimate the manhours of this work?

Thanks for your idea guys. Really appreciate it as im lack of the experience.

Hi Mohd

Experience is essential for a planner - if you can't build it you can't plan it - otherwise you are a scheduler working on someone elses plan.

The "Spons" books are a guide only - do not take the data as being relevant to your project as there are so many variables.

As I said earlier you need to go back to the estimated cost plan and speak to your estimator.

Best regards

Mike Testro

Mohd,

For piping: You must learn the so-called units: inch-dia and / or inch-meter

For structural steel: Tons and / or kilograms

It is really the experience that figure it out. 

Let us take your example:

Fabrication works, your reference is the Isometric drawing of 12 m pipe of 24" schedule 80 with 10 weld joint.

Can you identify what related tasks in the "Spons" book is applicable for estimating the manhours?

Also, the production rates in this book may not be applicable to your organisation productivity in the field? Do the operatives have the same skill? If not, what factor are you going to use? How about methods? Logistics? Materials? Equipment?

Suppose, there is no "Spons" book? How?

A planner with related experience can at least identify what tasks are needed for fabrication works of the pipe mentioned in your example.

As Mike has mentioned, speak to those people who are in the know.

Oo..thanks guy..now i got it... So what is the Spon's books norm were used for?.. I noticed that the unit they used in the table such as meter, numbers, etc.. So..what actually the norm were applicable for in the fabrication..

Sorry to ask such a silly question as this..but I really don't know about it...

Thanks for helping..

I realize that your original request was posted a few months ago, but in case you are still looking for resources, our eTaskMaker system includes estimating modules for piping demolition, fabrication and erection.  You can estimate (prepare manpower loaded execution schedules actually) piping work based off of engineering isometric diagrams.

Guys, Have a look at www.costeng.com their software tools provide automatic access to substantial manhour databases for spooling of pipework in a workshop and installation of spooled and site run pipework

How can one estimate the hours for installatio of structural members for offshore installation . this includes pipe hangers

Mohd Najib,

Everyone was 'new' someday and so don't worry thinking that your questions are silly. I will try to guide you a bit.

1. Schedule baseline will be loaded for the budgeted hrs (hrs included in the estimate)

2. Open the estiamte and you will see piping take off; it will show you the ISO's and the budgeted hrs.

3. I think that you will be scheduling at a FIWP level. This means you have to map the estimated hrs by FIWP.

4. Once you get to this level then we can talk about Rules of Credit etc.

Regards

Rashid

to estimate man hour piping you need more time experience , need investagation to gain some information from welding man power supply subcontractor. Because experience completeing piping fabrication time difference each place and condition.