Questions & Answers

Answer from Werner Sölken

Hi, Paul
Your mail ended up in my spam box; do not ask me why.

Today, April 1, 2015, I have seen your email for the first time, while you have sent in December 2014. Sorry about that!

I'm not going to stop my website ... as long as I live, I will pass my knowledge to others.

greetings Werner

thx

Answer from Werner Sölken

Hi Kiran Thomas,

Yes, you can calculate acceptable leakage for mechanical seals.

But, I can not give you an answer to your question; i do not know!

I hope you can appreciate my honest answer.

greetings Werner

Answer from Werner Sölken

Hi Asim,

Yes it is possible and permissible to use more than one type of pipes.

The internal, calculated pressure for a pipe, determine the type of pipe.

With a pipeline of 29km you have for example 200bar at the beginning of the pipeline, and at the end 180bar.

Somewhere in the pipeline, for example, then ERW type can be used, because the type of that (welded) pipe is suitable for the lower pressure.

Below, two references, who also tell us something about your question.

pressure rating (question 143)

pipeline segmentation (scroll down}

greetings Werner

Answer from Werner Sölken

Hi Robert,

What is the best connection? Tell me...
The shortest connection that you can make is..
Use a connector as shown above
Female:1/2 inch NPT (pipe OD 21.3mm) with a possibility to connect to 1/2 tubing.

By the way, it is ASME, and not ANSI.

greetings Werner

Answer from Werner Sölken

Hi Sarah,

Currently you can only choose the position of an 728x90 advertising, top, middle (between text) and at the bottom.

Your question.. Have you ever thought about selling your website?

My website is my profession!
I'm glad I could help a lot of people with my information.
I'm not doing this for money, but for the future of people who want to make the same buisness career, as I do.

greetings Werner

Answer from Werner Sölken

Hi Robin,

Control Valve Sizing

The line should be determined by an economic pipe sizing program.That will make the fluid velocity in the pipe stay within certain boundaries (not too slow or not too fast). If the flow is too slow, the pipe is probably larger than necessary which is more expensive to purchase and install. If the pipe is too small, the high fluid velocity will be noisy and probable erode the piping system.

The control valve needs to be sized using a pressure drop that is about equal to the system pressure drop (pipe friction + filters + heat exchangers ++). If the valve is sized with an arbitrary pressure drop of 10 pounds, it is a crap shoot as to it's ability to control. If the valve pressure drop is too low, the system will control the fluid flow, not the valve. If the pressure drop is too high, the valve may be much smaller than the pipe, noisy and probably wear out in a relatively short period of time. Also, the small valve, relative to the pipe size, may be under a great deal of stress when the pipe expands and contracts due to temperature changes.

So, in my vast experience as a valve sizer, they are usually smaller than the pipe. In order to get the valve to fit in a larger size pipe, you need 2 pipe reducers, one on each side.

If the valve and pipe are the same size, something is wrong. If the valve is larger than the pipe, everything is wrong and somebody spent a significant amount of money for a large valve and 2 reducers.

Reference(s).. www.chemicalprocessing.com

greetings Werner

Answer from Werner Sölken

Hi Robin,

I can not give you a clear answer to your question. I have searched in all the documentation available to me, but I could find an answer.

ASME says that there are differences, but why, that is not defined.

Short summary ASME B 36.19, Stainless Steel Pipe..

Pipes NPS 12 and smaller have outside diameters numerically larger than their corresponding sizes. In contrast, the outside diameters of tubes are numerically identical to the size number for all sizes.
The wall thicknesses for NPS 14 through 22 of Schedule 10S; NPS 12 of Schedule 40S; and NPS 10 and 12 of Schedule 80S are not the same as those of ASME B36.10M. The suffix "S" in the schedule number is used to differentiate B36.19M pipe from B36.10M pipe. ASME B36.10M includes other pipe thicknesses that are also commercially available with stainless steel material.
The size of all pipe is identified by the nominal pipe size.
The manufacture of pipe NPS 1/8 through NPS 12 is based on a standardized outside diameter (OD). This OD was originally selected so that pipe with a standard OD and having a wall thickness that was typical of the period would have an inside diameter (ID) approximately equal to the nominal size.
Although there is no such relation between the existing standard thicknesses - OD and nominal size - these nominal sizes and standard ODs continue in use as "standard."
The manufacture of pipe NPS 14 and larger proceeds on the basis of an OD corresponding to the nominal size.

greetings Werner

Answer from Werner Sölken

Hi Pedro,

Only for flanges you can talk about pressure rating. This is based on ASME 16.5 Class 150, Class 300 etc..Pressure rating does not apply to pipes.

If you want to fabricate a pipeline, according to a pressure rating of class 150, then the maximum pressure for these flanges are based on the ASME pressure rating tables.

Pipes and fittings are calculated and tested for internal pressure and various other features. These tests determine the wall thickness (schedule) of a pipe.

Usually this will be documented in a pipe specification (Pipe Spec.), which tells you the wall thickness for a pipe or fitting.

greetings Werner

Answer from Werner Sölken

Hi Sameer Moosa,

Take a look at.. calculate thickness of spacer

greetings Werner

Answer from Werner Sölken

Hi Rob,

In the past, I have worked often with AMEC.

Drafters had no computer, but an ordinary drawing board.
Maybe I'm old-fashioned, but "those were people who could make real drawings", which were easy to read for everyone.

That time is over, I have to accept drawings that ask more questions than provide answers.

By the way, thanks for your compliments on my website.

greetings Werner