Steps to Design a Piping System

To start; you do not give nowhere near enough information that first, atleast you could do the ground work on

What material are your piping, oil, steam, water, chemical?

Then you figure the viscosity of this product at the temperature?

Is this piping going to be ASME certified?

Do you also size the pumps?

Are these vessel accumulators, mixers, reactors? since these vessels are given to you, need the size of them. What are the specs on them? ASME, size, nozzles?

You may be a junior piping engineer, but you are still an engineer. You should still be able to do the preliminary's

Start looking into it, but there I'm sure will be more question coming, so don't go running to get the answers and only to realize there are more questions on the way.

At least look like you have things under control.

p911

This should be designed to 97/23 EC standard for pressure vessels as it comes under an assembly

This almost sounds like a school assignment.

it does sounds that way, but I had engineers fresh out of college, that lack basic practical experience, the hardest for them is getting started.

So, I'll give him the benefit of a doubt.

I'll point them in the right direction, and give them a push........I mean a nudge.

p911

Since you are a, "junior piping engineer" I assume that you have some education. I would also assume that there are "senior piping engineers" that would guide you.

"So, what is the steps in designing the right system?"

You take the first shot. Prove Ronsetto wrong.

List everything you know about the project, tell us the details.

Your turn.

This might be a good source to check out: http://www.pipingguide.com/

Ideally your company should have copies of the piping, structural, and pressure vessel codes that pertain to your location. If not, consider acquiring them on your own. There is some expense involved, so this may be a gradual process.

Similarly, see if your company has membership in professional societies such as AWS, ASME, IIAR, ASHRAE, API, etc. (or their local counterparts). You can join as an individual, but this too may be costly at the junior level. Again, it would be nice if your company can sponsor some individual or group memberships.

The original question is too wide-ranging to be answered by a few forum posts. However, if you flesh out your first example with some specific data, quite likely you will get some good advice.

Best of luck in this career!

In my experience, you have 3 major parties that participate in designing a piping system. A process (chemical) engineer, a piping (mechanical) engineer, and a piping designer.

The process engineer should provide the process data: temperature, flow rate, pressure, etc. The process engineer should then work with the piping engineer to match a material based on corrosion and various other mechanical properties.

As a piping engineer you should not be asking about how to find a pressure rating. I'll also give you the benefit of the doubt here though. Check ASME B31.3 and ASME B16.5.

Design temperature and pressure should be based on the maximum conditions the system can see. Check the definitions in ASME B31.3. These conditions will be determined by the process and piping engineer based on process needs and mechanical properties of the pipe.

Typically, a piping designer will design the system based on the above input. The process engineer will provide the diameter of pipe based on pressure drop calculations.

Thank you for the answer.

I'm a mechanical fresh grad, now working as a piping engineer.

1st of all, I know the inputs given are too brief, but what I would like to understand better the steps to design a piping system.

Looking at cingold's reply, I understand better.

1st - I need input from the process engineer all the process data as stated above.

2nd - To get the size required (diameter of pipe), based on flow rate and pressure drop calculation. This is done by the process eng. or piping eng.? Anyway, I am aware of the calculation.

3rd - Check all other possibilities for pressure surge, erosions, vibrations, temperature drop, flow pattern etc. What should we do with these details? I mean does it affect the material selection and other things as well?

4th - Depending on the input and process data, and max T and P, select the best pipe material.

5th - Determine the pressure-rating, pipe thickness from the calculation with corrosion allowance. Will check B31.3 n B16.5 for the idea, still unsure about this.

6th - Check the specifications of the piping materials, if it should be following ASME, ANSI or API standard. Get the details of the fittings, flange, gasket etc. Can the materials in a piping system has a mixture of different standard? Example, the Pipe following ASTM, the gasket ASME etc? Pls. enlighten.

I know it's not as simple as the abovementioned steps, but it should serve as an overview, right? Anything I forgot?

Are these steps sufficient to design a simple piping system?

Thanks.

Do you have a A process (chemical) engineer and a piping designer at your company or is that also your responsibility?.

Maybe I should have been more clear on the standards I provided (ASME standards). I'm not sure what country you're in but really what you typically need to follow is Good Engineering Practices. ASME B31.3 is a standard for the design of new pipe among other things. Unless this is required by law in your country, you don't have to follow it although it would still be a good idea.

As a piping or mechanical engineer, you are responsible for the mechanical aspects of that system. In particular, the mechanical integrity of the piping system. The process engineer should determine the pipe diameter along with the pipe designer so you can focus on the integrity of the system.

"3rd - Check all other possibilities for pressure surge, erosions, vibrations, temperature drop, flow pattern etc. What should we do with these details? I mean does it affect the material selection and other things as well?"

Your company needs some pipe specs. What you are describing here is the role of multiple different engineers. Yes this affects material selection. You need to get an expert or team of engineers to make some pipe specs to help your company out. Otherwise, some good standards to read are API 571 and a good Metals Handbook.

ASTM is a materials standard and ASME is a construction standard.

I think the biggest problem here is you are asking general questions and looking for specific answers.

Hi, you need to read and understand API 570, 510 and B31.8, first step you need is to buy these standards (not cheap!). Secondly, you need to read and understand. Then you don't need to post in forumns as if you have to design piping systems specially containing hydrocarbon, specifications, drawing and etc must be based on current standards available to ensure its safety, quality, integrity and reliabilty of your work! Not that easy I guess! Good luck anyway

It sounds like you need the assistance of a Senior Piping Designer or higher experienced Piping Designer. you do not state much in your request as to size of vessel, what it dose and what lines sizes and rating is required. Start with a Process Flow Diagram and develop a Piping and Instrumentation drawing to work out your requirements. Then you can work with a piping designer as to the layout to make sure the design meets stress, safety, operational and maintenance needs. As a Senior Principal designer I have had to correct many engineering design concept that do not operate correctly of that maintenance personal curse the inexperienced engineer that did not have the everyday operator or maintenance personal in mind when they laid the system out. I have also had to go on site to correct systems that were not stressed checked and damaged equipment. Also I have been on site as the construction crews stand around and laugh at engineering concepts that can not physically work.

In closing there are specialist for a reason. You would not go to a Gynaecologist to have your eyes checked out would you?

Robert F. Laurin

Senior Principal Mechanical Designer

Processes Unlimited International Inc

rflaurin@prou.com

best suggestion I heard yet.

GA

and as far as;

You would not go to a Gynaecologist to have your eyes checked out would you?

depends on where their head is?