Challenges of Pipe and Tube Testing
Presented by Instron®
A World Leader in Materials Testing
An overview of recent changes and challenges facing Pipe and Tube
manufacturers and suppliers
• Growth in Oil country tubular goods (OCTG)
• Shale gas horizontal drilling/fracking globally
• Multiple new pipelines planned in the US
Source: U.S. Energy Information Administration, Today in Energy, January 2, 2014.
Source: GreenCupboards, Fracking Debate, August 25, 2011.
Why is This Important?
• Horizontal drilling and fracking implications
• Increased length of pipe
• Increased strength
• Added multiple wells on a single site
• How does this affect your testing requirements?
• Increased load capacity and volume of testing
• Is your system ready for the changes heading your way?
Pipe & Tube Applications
• Are pipe & tube the same thing?
• Pipe = Nominal, ID (Inside Diameter)
• Tube = Nominal, OD (Outside Diameter)
• Pipe Applications • Tube Applications
Product Standards Link to Testing Standards
Mechanical Testing of
ANSI/API Spec 5L
Petroleum and natural
Steel pipe for pipeline
Petroleum and natural
Steel pipe for pipeline
Steel and steel
preparation of samples
and test pieces for
Bend Testing Charpy Impact
Your Testing Challenges
• Specimen geometry/curvature
• Testing full section pipe and tube
• Suitable strain measurement
• Impact testing high-strength materials
Challenge – Specimen Geometry
• The curved shape of pipe and tubing presents a number of gripping challenges.
Gripping Longitudinal Strips
• Application-specific jaw faces allow you to quickly grip longitudinal strip
curved cut out specimens, without flattening the tab ends.
Challenge – Testing Full Section Pipe/Tube
• Specimen preparation is time consuming; lab operators generally want to
test the largest full section of pipe possible on a given testing system.
Testing Full Section Product
• End plugs are used to prevent crushing
• Allows the testing of full product sections
• Removes the need to machine specimens from full product,
saving time and money
Challenge – Suitable Strain Measurement
• Pipe and Tube specimen geometries make attachment of extensometers
Suitable Strain Measurement
• An extensometer securely clamps the inner diameter of strip specimen,
preventing strain measurement errors due to slippage or undesired
movement on the curved specimen surface.
• A single instrument accommodates a wide range of specimen
diameters, reducing changes in test setup.
Challenge – Impact Testing High Strength
Pipe & Tube Materials
• Higher strength materials are being used in the pipe and tube industry in a
drive for deeper and more complex well production
• Increased impact energy
• Continual focus on improved safety
• Tractability of results
• Greater volume of tests
High-Energy Impact for Pipe & Tube
• Appropriate hammer weight, which fully
fractures specimen at impact, produces
accurate and reproducible results
• Interlocked safety screen prevents harm to
• Automatic recording of test results linked
directly into your business system
removes operator steps and opportunity
• Minimal number of steps required to run a
test allow increasing test volume per shift
Does this sound familiar?
Do you see the same challenges in your
for more information
Not the same. They are round, and hollow but slightly different Pipe size refers to nominal ID, not actual ID, or inside diameter Tube size refers to the nominal OD, or outside diameter
Pipe Applications Pipe used in the transportation of liquid petroleum for the oil and gas industry has been our primary application
Tube Applications Stainless tubing for boilers, heat exchangers, HVAC, etc. Tubing can also be used for construction applications such as square structural tubing for large buildings
Various pipe and tube product standard link back to one or more international testing standards. The goal behind this is so the testing procedures can be standardised, this also prevents the duplication of effort.
“The diversity of screw threads used to represent big problems for industry, particularly in maintenance, as lost or damaged nuts and bolts could not easily be replaced. A global solution is supplied in the ISO standards for metric screw threads.”
Test specifications permit “end flattening” prior to testing but it is time consuming, and difficult to achieve with thicker material
Satisfactory grip engagement is an issue with the curved surface, and specimen slippage can occur
Match the concave (curvature) portion of the longitudinal strip specimen Incorporates an interchangeable face for the concave portion of the specimen which can easily be equipped with different inserts to test various sizes of pipe and tube Uses a standard vee jaw to grip the convex portion of the specimen Standard flat jaw sets are available, and are suitable with thinner walled material In some instances using a standard flat jaw on the inside, and vee jaw on the outside can be successful
Gripping hollow material will cause crushing The grip jaw opening is the limiting factor in determining how large the pipe, or tube can be tested Therefore, a larger capacity system is often required since it can accept larger diameter test specimens
Add image of plug being installed into tube
Irregular geometry of pipe and tube can make choosing an extensometer for the application a bit challenging. Not all 50 mm (2 in) gage length clip on style instruments are created equal Longitudinal strips are curved Full section pipe can have a large diameter which limits choice of strain instruments
Instron model T3M Mill Type (W-6204) clip on instrument back support securely meets the contour of the inner portion of the longitudinal strip specimen. With interchangeable curved back support provided. Instron model T3M Mill Type (W-6204) clip on instrument can be used to test full section pipe with diameter up to 89mm. Uses vee style back support.
MPX motorized impact test system in 450-900 joule capacity with adjustable hammer energy capable of testing higher strength maraging steels, and newer alloys with Niobium, or Chromium Hammer energy is adjusted through use of different hammer weights that does not require hammer removal Conveniently located controls permit efficient operation to meet the 5 second loading requirement of ASTM E-23 & ISO 148 Motorized hammer, and interlocked guard protects technician from injury Easy to use software interface