Difference Between Pipe and Tube

While pipes and tubes may look similar, they are designed for different purposes and have distinct characteristics. Here’s a breakdown of their differences:

Difference between pipe and tube


1. Primary Purpose

FeaturePipeTube
Main UseTransport fluids/gases (e.g., water, oil, gas)Structural applications (e.g., frames, machinery, heat exchangers)
Pressure HandlingDesigned for high-pressure systemsTypically used for low-pressure applications
StandardizationFollows Nominal Pipe Size (NPS) and schedules (e.g., SCH 40, SCH 80)Measured by outside diameter (OD) & wall thickness (e.g., 1″ OD, 0.065″ wall)

2. Size & Dimensions

FeaturePipeTube
Size ReferenceNominal Pipe Size (NPS) – Approximate ID (not exact)Actual Outside Diameter (OD) – Precise measurement
Wall ThicknessDefined by schedule (e.g., SCH 40, SCH 80)Measured directly (e.g., 0.125″, 2mm)
TolerancesLooser tolerances (focus on pressure rating)Tighter tolerances (precision applications)

Example:

  • 1″ Schedule 40 Pipe has:

    • Outside Diameter (OD) = 1.315″

    • Inside Diameter (ID) ≈ 1.049″

  • 1″ Tube has:

    • OD = Exactly 1.0″

    • Wall thickness varies (e.g., 0.065″, 0.083″)


3. Shape & Flexibility

FeaturePipeTube
ShapeMostly round (some square/rectangular for structural use)Round, square, rectangular, oval
FlexibilityRigid, designed for fixed installationsCan be more flexible (e.g., hydraulic tubes)

4. Material & Manufacturing

FeaturePipeTube
MaterialsCarbon steel, stainless steel, PVC, CPVCSteel, aluminum, copper, brass, titanium
ProductionMade for large-scale fluid transportMade for precision applications (e.g., medical, aerospace)
Surface FinishRough (often coated for corrosion resistance)Smooth (polished for aesthetics/functionality)

5. Connection Methods

FeaturePipeTube
JoiningWelded, threaded, flangedWelded, brazed, compression fittings, flared ends
FittingsNPT (National Pipe Thread), socket weldFerrule fittings, push-to-connect

6. Applications

Common Uses of Pipes:

  • Water supply lines

  • Oil & gas pipelines

  • Plumbing & HVAC systems

  • Industrial process piping

Common Uses of Tubes:

  • Structural frameworks (e.g., handrails, scaffolding)

  • Hydraulic & pneumatic systems

  • Heat exchangers & condensers

  • Automotive & aerospace components


Quick Summary Table

AspectPipeTube
PurposeFluid/gas transportStructural/precision uses
Size ReferenceNominal Pipe Size (NPS)Exact OD & wall thickness
ShapeMostly roundRound, square, rectangular
TolerancesLooserTighter
Pressure HandlingHighLow-medium
Joining MethodThreaded, welded, flangedCompression, brazing, welding

When to Use Pipe vs. Tube?

  • Use Pipes for: Plumbing, oil/gas, high-pressure systems.

  • Use Tubes for: Structural support, machinery, precision applications.

Amar Patel
About Amar Patel 286 Articles
Hi, I am Amar Patel from India. Founder, Author and Administrator of mechnexus.com. I am a Simple Average Man who Loves life and Love living life. Professionally I am a Mechanical Engineer with Solid command over CAD software like FreeCAD, SolidWorks, Autodesk Inventor and AutoCAD Mechanical. I’m here to share my knowledge to help you accomplish your design and engineering tasks quicker and easier. I am Passionate about learning new things especially about Open-Source Software. I love teaching therefore I started my YouTube Channel on FreeCAD and I believe FreeCAD have lots of potential than traditional 3D software. contact me - amar.bahadur@outlook.com