Dear All,
I proposed number of answers... The best you choose according to you,
1)What's the difference between a pipe and a tube?
Ans: More often than not, people guess it has something to do with the quality of the materials, but that's got nothing to do with it. The difference between a pipe and a tube is how they are measured, and ultimately what they are used for.
A pipe is a vessel - a tube is structural.
A pipe is measured ID - a tube is measured OD.
How they are measured... Pipes are measured ID or inside diameter because they are vessels. Tubes are measured OD or outside diameter because they are structural.
Pipes have a consistent ID regardless of wall thickness. In other words, a 1/2" high pressure pipe may need a 2" thick wall, but the ID will still only be 1/2" even tho the OD is 4.5".
Generally speaking, a tube will have a consistent OD and it's ID will change. Engineers see tubes and pipes with different eyes.A tube is structural.By having a consistent OD they can vary wall thickness, changing the ID, to increase strength. Because they are consistent OD, they have predictable characteristics.
Again, the difference is simple, it's how they are measured and what their intended uses.
2nd answer: actually tube is used when we need to transfer heat from its walls and we want this to be happen while in pipes we try to stop the heat transfer such as we use tubes in boilers because we mak steam we need to transfer the heat while when we transporate steam we use pipes because we wana save heat energy.
2: pipe can be thick according to formula d/t >10 while tube will must thin according to this formula.
3rd answer: *pipe size refers to a nominal – not actual – inside pipe diameter. Schedule refers to the pipe's wall thickness. The dimensions provided for tubing on the other hand refer to the actual outside diameter.
For example: The actual outside diameter of 1¼" pipe is 1.625" – while 1¼" tube has a true 1.25" outside diameter.
*The inside diameter of a tube will depend on the thickness of the tube. The thickness is often specified as a gauge. If we look at Copper Tubes - ASTM B88 the wall thickness of 0.083"of a 2" pipe is gauge 14.
*The tolerances are higher with tubes compared to pipes and tubes are often more expensive to produce than pipes.
*Since the outside diameter of a single nominal pipe size is kept constant [upto 12" NB] the inside diameter of a pipe will depend on the "schedule" or the thickness of the pipe. The schedule and the actual thickness of a pipe varies with the size of the pipe.
It is common to identify pipes in inches by using NPS or "Nominal Pipe Size". The metric equivalent is called DN or "diametre nominel". The metric designations conform to International Standards Organization (ISO) usage and apply to all plumbing, natural gas, heating oil, and miscellaneous piping used in buildings. The use of NPS does not conform to American Standard pipe designations where the term NPS means "National Pipe Thread Straight".
Nominal Bore (NB) may be specified under British standards classifications along with schedule (wall thickness).
The tolerances are looser to pipes compared with tubes and they are often less expensive to produce.
In short:
"A pipe is a tube or hollow cylinder used to convey materials or as a structural component. The terms pipe and tube are almost interchangeable. A pipe is generally specified by the internal diameter (ID) whereas a tube is usually defined by the outside diameter (OD) but may be specified by any combination of dimensions (OD, ID, wall thickness). A tube is often made to custom sizes and may often have more specific sizes and tolerances than pipe. Also, the term tubing can be applied to non-cylindrical shapes (i.e. square tubing). The term tube is more widely used in the United States, whereas pipe is more common elsewhere in the world. "
-Tube is available in coil form, not pipes due to the simple fact that pipe wall thickness does not permit coiling.
4th Answer:What is the difference between Pipe and Tube?
IPS stands for iron pipe size – a standard that was originally developed for fluid transfer but has also become the standard for designating handrail sections in all alloys.
There is often confusion as to which size product the customer actually needs – Pipe Size or OD Tubing Size.
Keep in mind that pipe size refers to a nominal – not actual – inside pipe diameter. Schedule refers to the pipe's wall thickness. The dimensions provided for OD tubing on the other hand refer to the actual outside diameter and wall thickness.For example: 1-1/2" pipe size flanges have an opening to fit over 1.90" OD – the actual outside diameter of 1-1/2" pipe – while 1.50" OD tubing has a true 1.50" outside diameter and the flange is sized accordingly.
Yadav Shiva Chelliya,
Inspection Engineer,
Doha Qatar,
+974-6166465On Tue, Apr 6, 2010 at 2:26 PM, Edgar A Coello <idco@tpg.com.au> wrote:Hi there,
Just for clarification, tubes will have consistent ID and variable OD. I think that is what you mean below so an small correction where is underlined might be required.
Kind Regards,
Edgar A Coello, MIEAust, CPEng, RPEQ.
Mobiles +61407954162
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of agmendoza@cantv.net
Subject: Re: [MW:4705] Difference between pipes and tubes
Sent: Tuesday, 6 April 2010 5:46 AM
More often than not, people guess it has something to do with the quality of the materials, but that's got nothing to do with it. The difference between a pipe and a tube is how they are measured, and ultimately what they are used for.
A pipe is a vessel - a tube is structural.
A pipe is measured ID - a tube is measured OD.
How they are measured.
Pipes are measured ID or inside diameter because they are vessels. Tubes are measured OD or outside diameter because they are structural.
Pipes have a consistent ID regardless of wall thickness. In other words, a 1/2" high pressure pipe may need a 2" thick wall, but the ID will still only be 1/2" even tho the OD is 4.5".
Generally speaking, a tube will have a consistent OD and it's ID will change. Engineers see tubes and pipes with different eyes.
A tube is structural.
By having a consistent OD they can vary wall thickness, changing the ID, to increase strength. Because they are consistent OD, they have predictable characteristics.
Again, the difference is simple, it's how they are measured and what their intended uses are.
Kind regards.
Gustavo Mendoza.
QA/QC Inspector.
abr 4, 2010 04:07:22 AM, materials-welding@googlegroups.com wrote:
===========================================
Hai all,
1.Please somebody can explain difference between pipes and tubes with some references.
2. In our project continuously getting repair ( Cold lap) in hot and fill pass. can u suggest some good way to avoid or rectify this.
material Used - CS dia 68,64 and 60"
Process : Root - STT, Other - FCAW shielding by gas ( Ar80%, CO2 20%- 48 CFH)
Filler metal for FCAW : A5.20 E71T-9M
Expecting reply as soon as possible.
Regards,
Meera
--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.--To unsubscribe, reply using "remove me" as the subject.
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
--
--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
--
Regards
B.K.Shah
00974 6989344
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
No comments:
Post a Comment