Mastering Metric Tubing: Sizes, Materials, and Applications

As a professional seeking reliable and high-quality tubing, understanding sizes, materials, and applications is crucial. This guide will provide essential insights into metric tubing, empowering you to make informed decisions for your projects and business needs. Let’s explore this fascinating subject together.

What is Metric Tubing?

Metric Tubing

Metric tubing, a versatile product, comes in various materials, sizes, and thicknesses. Its dimensions are measured in millimeters, making the sizing precise and easy to compare.

You will find metric tubing used in countless industries, such as automotive, aerospace, medical, and food processing. Stainless steel, a popular choice for metric tubing, offers exceptional strength, durability, and corrosion resistance. Its versatility allows for use in high-temperature and high-pressure applications.

Plastic metric tubing, another common material, provides flexibility, chemical resistance, and affordability. You will find plastic tubing used in medical devices, food processing equipment, and fluid transport systems.

Common sizes for plastic tubing include 3mm to 50mm OD and wall thicknesses from 0.5mm to 2.5mm. Aluminum and copper metric tubing also have specific applications.

Copper tubing, known for its excellent thermal conductivity, is commonly used in HVAC systems and plumbing. Understanding metric tubing’s various materials, sizes, and applications helps you choose the right one!

Metric Tubing Sizes

Understanding metric tubing sizes is crucial for various industries, as it ensures proper material selection and functionality. Now, you will learn about the metric measurement system, standard metric tubing sizes, and how to measure them accurately.

  • Explanation Of Metric Measurement System

The metric system, based on units of 10, is a widely used international standard. In the metric system, length is measured in meters (m), while smaller units include centimeters (cm) and millimeters (mm). One meter is equal to 100 centimeters or 1,000 millimeters. The metric system is preferred for its simplicity and ease of conversion between units.

For tubing, metric measurements are crucial in specifying dimensions accurately.

Each dimension is typically measured in millimeters to ensure precision and ease of communication across industries.

  • Standard Metric Tubing Sizes

  • Outer Diameter (OD)

The outer diameter is the distance from one outside edge of the tube to the opposite outside edge, measured in millimeters. Standard metric tubing sizes range from 1.5 mm to 450 mm OD. For specific applications, you may find tubes with a larger or smaller OD, but these are less common. Accurate OD measurements are essential for proper fitting and sealing in various applications.

  • Inner Diameter (ID)

The inner diameter is the distance from one inside edge of the tube to the opposite inside edge, also measured in millimeters. It directly affects the flow capacity and pressure resistance of the tubing. Standard metric tubing sizes for ID typically range from 0.8 mm to 400 mm. The ID is crucial for determining the tubing’s compatibility with various fluids or materials passing through it.

  • Wall Thickness

Measured in millimeters, wall thickness can vary depending on the tubing’s material and application. Common metric wall thicknesses range from 0.5 mm to 50 mm. A thicker wall provides higher pressure resistance and mechanical strength, while a thinner wall offers reduced weight and cost.

  • How To Measure Metric Tubing?

Measuring metric tubing accurately ensures proper functionality and compatibility. Follow these steps for precise measurements:

  1. Use a caliper or micrometer for precise measurements of the outer diameter, inner diameter, and wall thickness.
  2. Measure the outer diameter by placing the caliper or micrometer jaws on the tubing’s outer edges and noting the reading.3.
  3. To measure the inner diameter, insert the caliper or micrometer’s inside jaws into the tubing and record the reading.
  4. Calculate the wall thickness by subtracting the inner diameter measurement from the outer diameter measurement and dividing the result by two.

By understanding and accurately measuring metric tubing sizes, you can ensure proper material selection and functionality for your projects. Always consider the application’s requirements and adhere to industry standards for a successful outcome.

Metric Tubing Materials

Metric Tubing Materials

  • Common Metric Tubing Materials: Delve into the world of materials used in metric tubing. Explore the common ones and find out which suits your needs best.
  • Stainless Steel: stainless steel tubing offers corrosion resistance, strength, and durability. Industries like automotive, aerospace, and construction benefit from its properties. In marine environments, you’ll find Grade 316 stainless steel for increased corrosion resistance.

With high tensile strength, stainless steel tubing can handle pressure in hydraulic and pneumatic systems. Metric dimensions allow for easier integration in global projects.

When selecting tubing, consider wall thickness for pressure requirements and weight restrictions. You’ll find options like 304 and 316L grades, with varying strength and corrosion resistance levels. Stainless steel’s recyclability ensures sustainability in production, and its long-lasting nature makes it a cost-effective choice.

Its resistance to extreme temperatures makes it suitable for heat exchangers, chemical processing plants, and cryogenic applications.

  • Copper: Copper tubing provides excellent thermal and electrical conductivity, making it ideal for electrical wiring, HVAC systems, and plumbing. With its flexibility, copper tubing can be bent easily without compromising structural integrity, simplifying installation.

Copper’s antimicrobial properties prevent bacterial growth, ensuring safe water supply systems. Copper tubing comes in various wall thicknesses, allowing you to choose the right balance between strength, weight, and cost.

Its corrosion resistance protects against harsh environments, prolonging the tubing’s lifespan. With metric sizing, copper tubes fit seamlessly into international projects.

Copper’s recyclability contributes to sustainable production, reducing the overall environmental impact. Its durability leads to long-term savings, as maintenance and replacement costs are minimized.

  • Aluminum: Aluminum tubing offers lightweight strength, corrosion resistance, and excellent thermal conductivity. Industries like aerospace, automotive, and construction appreciate its high strength-to-weight ratio.

Its malleability allows for easy bending and shaping, simplifying manufacturing processes. Metric sizing ensures compatibility with international projects. Wall thicknesses can be adjusted to achieve the desired balance between weight and strength.

Aluminum’s recyclability and abundance make it an eco-friendly choice. Its ability to disperse heat effectively makes it suitable for heat exchangers, radiators, and air conditioning systems.

  • Brass: Brass tubing combines strength, corrosion resistance, and aesthetics. Its unique gold-like appearance makes it popular in decorative applications, such as handrails and architectural elements.

Industries like plumbing and instrumentation value brass tubing for its durability and resistance to wear. Brass tubes come in various alloys, providing a range of mechanical properties and corrosion resistance.

Metric dimensions ensure seamless integration in global projects. Adjust wall thicknesses to meet pressure and weight requirements.

Brass’s machinability and formability make it easy to work with, reducing manufacturing costs. Its ability to withstand high temperatures makes it suitable for applications like steam and hot water systems.

  • Plastic (E.G., PVC, PEX): Plastic metric tubing, including PVC and PEX, offers flexibility, lightweight strength, and cost-effectiveness. PVC tubing is commonly used in plumbing, drainage, and irrigation systems due to its durability and resistance to chemicals.

PEX tubing, popular for radiant floor heating and residential plumbing, boasts excellent flexibility and resistance to temperature fluctuations. Both PVC and PEX tubing are available in metric sizes, ensuring compatibility with global projects.

Wall thicknesses can be adjusted for different pressure and durability requirements. These materials are easy to install and maintain, reducing labor costs and downtime.

  • Specialty Materials
  • Titanium: Titanium tubing boasts exceptional strength-to-weight ratio, corrosion resistance, and biocompatibility. Titanium’s lightweight strength makes it ideal for aircraft components, while its biocompatibility allows for medical implants and prosthetics.

Available in various grades and metric dimensions, titanium tubing can be tailored to specific project requirements. Wall thicknesses can be adjusted to balance weight, strength, and cost.

Titanium’s resistance to corrosive environments makes it suitable for applications in marine and chemical processing industries.

  • Nickel Alloys: Nickel alloy tubing offers exceptional corrosion resistance, high-temperature stability, and strength. Industries like aerospace, chemical processing, and power generation value nickel alloys for their ability to withstand harsh environments.

Common nickel alloys include Inconel, Monel, and Hastelloy, each with distinct properties and applications. Metric dimensions allow for compatibility in international projects, while wall thicknesses can be customized for specific pressure and weight requirements.

Nickel alloy tubing’s resistance to oxidation and corrosion makes it suitable for use in extreme conditions, such as high-temperature or chemically aggressive environments.

  • Glass And Ceramic: Glass and ceramic tubing offer unique properties, such as electrical insulation, thermal stability, and chemical resistance. Glass tubing is popular for laboratory applications, while ceramic tubing is used in high-temperature or corrosive environments.

Metric sizing ensures seamless integration in global projects, and wall thicknesses can be adjusted for specific strength and weight requirements.

Glass and ceramic tubing provide excellent resistance to chemicals and can withstand high temperatures without compromising structural integrity.

  • Material Properties And Selection Criteria
  • Strength And Durability: When choosing metric tubing, consider materials with high tensile strength (above 500 MPa) and yield strength (above 350 MPa) for optimal durability.

Materials like 316 stainless steel exhibit excellent strength-to-weight ratios, ensuring long-lasting and reliable tubing for various applications.

  • Rust Protection: Select corrosion-resistant materials, such as 304 or 316 stainless steel, to prevent rust formation.

With chromium content above 10.5%, these materials create a protective oxide layer, offering superior rust protection and reducing maintenance costs for your metric tubing projects.

  • Handling Temperature Extremes: Metric tubing materials should withstand temperature extremes. For instance, stainless steel grades 304 and 316 perform well in temperatures up to 870°C (1598°F) and 925°C (1697°F), respectively. Such temperature resilience makes them suitable for applications in heat exchangers or high-temperature environments.
  • Flexibility versus Rigidity: Determine your tubing’s required flexibility or rigidity. For instance, annealed stainless steel tubing offers more flexibility, while cold-drawn tubing provides increased rigidity. The Young’s modulus of stainless steel is around 200 GPa, making it an ideal choice for structural applications requiring sturdiness.
  • Keeping An Eye On Costs: Evaluate material costs by comparing prices per kilogram or meter. Stainless steel, for example, costs $2 to $4 per kilogram, depending on the grade. Consider factors like fabrication, maintenance, and lifecycle costs to ensure you select the most cost-effective metric tubing material for your specific needs.
Material Strength & Durability Rust Protection Temperature Resistance Flexibility vs Rigidity Cost
Stainless Steel High High High Rigid Moderate
Copper Moderate High Moderate Flexible Moderate
Aluminum Moderate Moderate Moderate Rigid Budget-Friendly
Brass Moderate High Moderate Rigid Moderate
Plastic (PVC, PEX) Low Low Low Flexible Budget-Friendly
Titanium High High High Rigid Expensive
Nickel Alloys High High High Rigid Expensive
Glass & Ceramic Moderate High High Rigid Moderate

Comparison Chart

Metric Tubing Shapes and Dimensions

Metric Tubing Shapes

Let’s talk about metric tubing shapes and dimensions. We’ve got a variety of tubing forms to discuss, each with its unique features. Ready? Let’s dive in!

  • Metric Square Tubing

You’ll find metric square tubing in a plethora of dimensions, with a typical range from 10×10 mm to 400×400 mm. Also, various wall thicknesses, often between 1.0 mm and 20 mm, offer versatility. You may encounter diverse materials such as stainless steel, carbon steel, and aluminum.

Consider crucial specifications like tensile strength, yield strength, and elongation percentage. Gauge the accuracy of dimensions, weight per meter, and surface area to ensure compatibility with your projects.

  • Metric Rectangular Tubing

Metric rectangular tubing dimensions span from 20×10 mm to 500×300 mm, with wall thicknesses ranging from 1.0 mm to 22.0 mm. Assess vital properties like tensile strength, yield strength, and elongation percentages of materials, including stainless steel, carbon steel, and aluminum.

Confirm the accuracy of dimensions, weight per meter, and surface area. Evaluate straightness and perpendicularity to ensure uniformity and integrity across applications.

  • Metric Round Tubing

In metric round tubing, diameters vary from 3.0 mm to 450 mm, while wall thicknesses can range from 0.5 mm to 20 mm. Materials used include stainless steel, carbon steel, and aluminum. Consider mechanical properties such as tensile strength, yield strength, and elongation percentage.

Verify dimensions, weight per meter, and surface area to ensure seamless integration into your projects. Examine the roundness and concentricity to maintain precision and accuracy.

  • Other Shapes And Dimensions
  • Metric DOM (Drawn Over Mandrel) tubing

Metric DOM tubing offers diameters from 12.7 mm to 203.2 mm and wall thicknesses from 1.5 mm to 12.7 mm. You’ll find enhanced dimensional tolerances and improved mechanical properties due to its unique manufacturing process.

  • Metric-Honed Cylinder Tubing

Metric-honed cylinder tubing provides diameters between 40 mm and 500 mm, with wall thicknesses from 5 mm to 25 mm. Honing processes yield superior surface finishes and enhanced dimensional accuracy, crucial for hydraulic and pneumatic applications.

  • Metric Hypodermic Tubing

Metric hypodermic tubing, with diameters from 0.4 mm to 8.0 mm and wall thicknesses from 0.1 mm to 0.5 mm, exhibits high precision in medical applications. The tubing’s small size and tight tolerances allow for exacting usage in various medical procedures.

  • Metric Mechanical Tubing

Metric mechanical tubing covers a wide range of dimensions, with diameters from 6 mm to 250 mm and wall thicknesses from 1 mm to 20 mm.

Metric Tubing Applications

Metric Tubing Applications

  • Tubing & Metric Hydraulics

Metric hydraulic tubing is crucial in fluid power applications. You’ll find it in construction equipment, industrial machines, and automotive systems. Common sizes range from 4mm to 42mm OD, with pressure ratings up to 630 bar.

  • Hydraulic Tubing Sizes And Materials

Metric tubing comes in various materials like stainless steel, carbon steel, and copper. Stainless steel 316L is popular for its corrosion resistance. Standard sizes include 6mm, 8mm, and 10mm OD, with wall thicknesses of 1mm to 2.5mm.

  • Hydraulic Tubing Suppliers

Choose a reliable supplier for high-quality metric tubing. Ensure they offer traceability, certifications, and adherence to industry standards like DIN 2391 and ISO 8434. Top suppliers serve various industries globally.

  • Metric Air Brake Tubing

In transportation, metric air brake tubing is vital for efficient brake systems. Nylon and polyamide are common materials, providing flexibility and durability. Sizes range from 6mm to 16mm OD, with working pressures up to 20 bar.

  • Sizes And Materials

Nylon 11 and 12 are popular for air brake tubing, offering UV resistance and flexibility. Common sizes include 8mm, 10mm, and 12mm OD, with wall thicknesses of 1mm to 1.5mm. Ensure compliance with SAE J844 and DIN 74324 standards.

  • Applications In Transportation

Metric air brake tubing is essential in commercial vehicles like trucks, buses, and trailers. Its reliability ensures efficient braking and improved safety. You’ll also find it in rail transport and heavy machinery.

  • Metric Pneumatic Fittings And Tubing

Metric pneumatic tubing is used in automation and control systems. Polyurethane and nylon materials are popular choices, providing flexibility and kink resistance. Sizes range from 4mm to 16mm OD, with pressure ratings up to 20 bar.

  • Materials And Sizes

Polyurethane is widely used for its flexibility and durability. Standard sizes include 6mm, 8mm, and 10mm OD, with wall thicknesses of 1mm to 1.5mm. Ensure compliance with ISO 6432 and ISO 15552 standards for optimal performance.

  • Applications In Automation And Control Systems

Metric pneumatic tubing is vital in industries like robotics, assembly lines, and packaging. You’ll find it in pneumatic cylinders, valves, and air preparation equipment. It ensures smooth operation and precise control.

  • Metric Exhaust Tubing

Exhaust systems rely on metric tubing for efficient gas flow. Stainless steel and aluminized steel are popular materials, providing heat resistance and durability. Sizes range from 25mm to 102mm OD, with wall thicknesses of 1.2mm to 2mm.

  • Materials And Sizes

Stainless steel 304 and 409 are commonly used for exhaust tubing. Standard sizes include 38mm, 51mm, and 63mm OD, with wall thicknesses of 1.5mm to 2mm. You should ensure compliance with ASTM A269 and A554 standards for optimal performance.

  • Applications In Automotive And Industrial Systems

Metric exhaust tubing is essential in automotive systems like cars, motorcycles, and trucks. It ensures efficient gas flow and reduced emissions. You’ll also find it in industrial equipment like generators and boilers.

  • Other Applications
  • Metric Vacuum Tubing

Metric vacuum tubing is crucial in applications like laboratory equipment, pneumatic conveying, and process control. PVC, silicone, and rubber materials are common, offering flexibility and vacuum resistance.

Sizes range from 6mm to 50mm OD, with wall thicknesses of 1mm to 3mm. Metric vacuum tubing provides reliable connections and precise control in various industries.

  • Metric Sanitary Tubing

In the pharmaceutical, food, and beverage industries, metric sanitary tubing is essential. Stainless steel 304 and 316L materials offer corrosion resistance and hygienic surfaces.

Sizes range from 12mm to 102mm OD, with wall thicknesses of 1.2mm to 2.5mm. Compliance with standards like ASME BPE ensures safety and cleanliness.

  • Metric Structural Tubing

Metric structural tubing plays a vital role in the construction, automotive, and aerospace industries. Common materials include carbon steel, stainless steel, and aluminum. Sizes range from 20mm to 150mm OD, with wall thicknesses of 1.5mm to 5mm. Metric structural tubing offers strength and durability for various load-bearing applications.

Metric Tubing Fittings, Tools, and Accessories

When you’re working with metric tubing, you’ll come across a range of fittings, tools, and accessories that ensure the perfect connection. Let’s take a look at compression fittings, wrenches, and benders that’ll make your project a success!

  • Metric Tubing Compression Fittings

You’ll find metric tubing compression fittings essential for connecting tubes securely. Common materials include brass, stainless steel, and plastic. The size range is between 3 mm to 42 mm. DIN 2353 fittings follow international standards.

There are three types: light, heavy, and extra-heavy series. Each series serves different applications. Light series suits low-pressure and thin-walled tubing.

Heavy series works for high-pressure systems. Extra-heavy series is perfect for extremely high-pressure conditions. Popular fitting types are straight, elbow, tee, and cross. Remember; always choose the right fitting type and size for your tubing needs.

  • The Must-Have Metric Tubing Wrenches

A proper metric tubing wrench is crucial for successful installations. Flare nut wrenches are essential for tube fittings. They prevent damage and ensure tight connections. Sizes range from 6 mm to 24 mm. Combination wrenches are also helpful.

They have open and box ends, suitable for various tasks. Ratcheting wrenches offer speed and convenience. Adjustable wrenches provide versatility for different fitting sizes.

Invest in a high-quality wrench set. Look for features like corrosion resistance and a comfortable grip. A durable, precise wrench set makes your work more efficient.

  • Metric Tubing Benders

Metric tubing benders are indispensable for shaping tubes without damage. Manual benders work for most small to medium jobs. Hydraulic benders offer more power and precision. Choose the right bender based on your project requirements.

Benders come in various radius sizes, like 10 mm, 15 mm, and 25 mm. Select the right radius for your specific tubing. Bending shoes help avoid kinks and ensure accuracy. Remember, using the correct bender and accessories will lead to successful, professional results.

  • Other Fittings And Accessories
  • Metric Pneumatic Fittings

Metric pneumatic fittings are crucial for air systems. They connect tubes, pipes, and hoses. Common materials include brass, stainless steel, and plastic.

Push-to-connect fittings allow fast, secure connections. Sizes range from 4 mm to 16 mm. Barbed fittings work for flexible tubing. Look for high-quality fittings to ensure durability and leak prevention.

  • Metric Vinyl Tubing

Metric vinyl tubing offers flexibility and chemical resistance. It’s perfect for low-pressure fluid transfer. You’ll find sizes ranging from 3 mm to 19 mm.

Vinyl tubing is lightweight and easy to handle. Use it with compatible compression fittings for a secure connection. Always select the right size and type for your project.

  • Nalgene 180 PVC Metric Tubing

Nalgene 180 PVC metric tubing is a popular choice. It’s flexible, durable, and chemically resistant. Suitable for food, beverage, and lab applications, it comes in sizes from 4 mm to 19 mm. Use it with compatible fittings for the best results. Nalgene 180 PVC tubing meets high-quality standards, ensuring reliability.

  • Nylon Tubing Metric

Nylon tubing metric is ideal for pneumatic and hydraulic systems. It’s strong, flexible, and lightweight. It offers excellent chemical resistance. You’ll find sizes ranging from 3 mm to 28 mm. Use nylon tubing with appropriate fittings for a secure connection. Nylon tubing delivers great performance and durability in various applications.


To wrap it up, being well-versed in metric tubing can truly enhance your projects. When you have a solid grasp of the various sizes, materials, and applications, selecting the ideal tubing for your requirements becomes a breeze.

Metric tubing is indispensable in numerous industries, such as hydraulic systems, transportation, and various industrial applications. Don’t overlook the importance of fittings, tools, and accessories to help you accomplish your tasks seamlessly.

Visit TuoLian for a dependable source of metric tubing and professional guidance. The experienced staff at will lead you through the process, making sure your decisions are well-informed and tailored to your projects. Embrace your journey to becoming a metric tubing connoisseur with by your side!

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Whether you need stainless steel materials for your business or fabrication projects, TuoLian is your best supplier. You can find all types, grades, and thicknesses based on your needs. Guaranteed that we provide the best quality at a reasonable cost.
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