Copper Type K L M Pipe Size PDF
Products Description
Choose C68700 (Arsenical Aluminum Brass): When initial cost is the primary driver and the seawater is known to be clean, of good quality, and at moderate velocities. It is an economical and practical choice.
Upgrade to C70600 (90/10 CuNi): When facing more challenging conditions (high velocity, risk of pollution, severe biofouling) or seeking longer service life and lower maintenance costs, the investment in the more durable C70600 is justified.
Customer Visit & Project Reference – India
We successfully supplied ASTM B111 C68700 aluminum brass tubes to a customer in India for shell & tube condenser applications. During the project, the customer visited our facility for production inspection and quality verification. All tubes were manufactured in accordance with ASTM B111 requirements and delivered with complete Material Test Certificates (MTC), ensuring full heat number traceability and verified chemical and mechanical properties.
Download ASTM B111 C68700 MTC (PDF)
Chemical Composition Comparison
| Element / Property | C70600 (90/10 CuNi) | C68700 (Arsenical Aluminum Brass) | Notes |
|---|---|---|---|
| Copper (Cu) | 86.5 % min. | 76.0 % min. | Base for both alloys |
| Nickel (Ni) | 9.0 - 11.0 % | - | Key difference: C70600 contains Ni |
| Zinc (Zn) | 1.0 % max. | 20.0 - 23.0 % | Key difference: C68700 contains high Zn |
| Aluminum (Al) | - | 1.7 - 2.3 % | Key for C68700's protective film |
| Iron (Fe) | 1.0 - 1.8 % | 0.06 % max. | Fe is essential in C70600 for corrosion resistance |
| Manganese (Mn) | 0.5 - 1.0 % | - | Mn deoxidizes and strengthens C70600 |
| Arsenic (As) | - | 0.02 - 0.10 % | Added to C68700 to inhibit dezincification |
| Lead (Pb) | 0.05 % max. | 0.07 % max. | Impurity controlled in both |
| Tin (Sn) | 0.03 % max. (O60) | - | - |
| Other Impurities | 0.1 % max. | - | - |
| Identification | Copper-Nickel Alloy | Brass | Fundamental material family difference |
Physical Properties Comparison
| Property | C70600 (90/10 CuNi) | C68700 (Arsenical Aluminum Brass) | Implications |
|---|---|---|---|
| Density | 0.323 lb/in³ (8.94 g/cm³) | 0.302 lb/in³ (8.36 g/cm³) | C68700 is about 7% lighter than C70600. |
| Melting Point | 2140-2260°F (1170-1240°C) | 1660-1710°F (905-930°C) | C70600 has a significantly higher melting range. |
| Thermal Conductivity | 29 Btu/(ft·h·°F) (50 W/m·K) | 58 Btu/(ft·h·°F) (100 W/m·K) | C68700 is about twice as thermally conductive. A major advantage for heat transfer. |
| Electrical Conductivity | 9% IACS (at 68°F) | 23% IACS (at 68°F) | C68700 is a better electrical conductor. |
| Modulus of Elasticity (Tension) | 22 x 10⁶ psi (152 GPa) | 16 x 10⁶ psi (110 GPa) | C70600 is stiffer (higher modulus). |
| Coefficient of Thermal Expansion | 9.4 x 10⁻⁶ per °F (68-572°F) (16.9 x 10⁻⁶ per °C) |
11.2 x 10⁻⁶ per °F (68-572°F) (20.2 x 10⁻⁶ per °C) |
C70600 expands less with heat, beneficial for thermal stability. |
| Specific Heat Capacity | 0.09 Btu/lb·°F (390 J/kg·K) | 0.09 Btu/lb·°F (380 J/kg·K) | Similar capacity to store heat energy. |
| Magnetic Response | Essentially Non-Magnetic | Non-Magnetic | Both are suitable for applications requiring non-magnetic materials. |
Mechanical Properties Comparison
| Property | C70600 (90/10 CuNi) | C68700 (Arsenical Aluminum Brass) | Implications |
|---|---|---|---|
| Tensile Strength | 44,000 psi (303 MPa) | 54,000 psi (372 MPa) | C68700 in the annealed condition has a higher ultimate strength. |
| Yield Strength (0.5% Ext under Load) | 18,000 psi (124 MPa) | 22,000 psi (152 MPa) | C68700 has a higher yield strength in the annealed condition. |
| Elongation (in 2 inches) | 30 % | 50 % | C68700 is significantly more ductile in the annealed temper, making it easier to bend and form. |
| Hardness | Rockwell F 65 | Rockwell B 50 | Different scales are typically used. C70600 is generally harder. |
| Fatigue Strength | Good | Good | Both have good resistance to cyclic loading in marine environments. |
| Poisson's Ratio | 0.33 | 0.33 | Similar deformation behavior under load. |
| Machinability | 20 % (Free-Cutting Brass = 100%) | 30 % (Free-Cutting Brass = 100%) | Both have fair machinability. C68700 is generally easier to machine than C70600. |
How to Choose
Choose C68700 (Aluminum Brass) if:
Your budget is the primary constraint.
The seawater source is clean, fully oxygenated, and unpolluted (e.g., open ocean intake).
Water velocities are moderate and non-turbulent (typically below 2.5 m/s).
Maximum heat transfer efficiency is desired, and the water quality allows for the use of brass.
Choose C70600 (90/10 CuNi) if:
Long-term reliability and reduced maintenance are prioritized over initial cost.
The seawater is or could be polluted (e.g., from harbors, industrial discharge, sewage).
The system will experience high water velocities or turbulent flow.
Resistance to biofouling is critical to minimize cleaning downtime.
The operating environment is variable or not perfectly controlled.
Typical Application Scenarios
C70600 Applications:
Offshore oil & gas platform cooling systems.
Shipboard condensers and heat exchangers (especially for vessels traveling between various ports).
Desalination plant heat rejection sections.
Systems using high-speed water jetting or with sand entrainment.
C68700 Applications:
Power plant surface condensers with clean seawater sources.
Industrial heat exchangers using treated or clean coastal water.
Various cooling circuits where water chemistry is tightly controlled and cost is a major factor.
Quality Inspection of C68700 and C70600 Tubes
Quality Inspection of C68700 and C70600 Tubes
To ensure consistent quality and compliance with ASTM B111, every batch of C68700 Aluminum Brass Tubes and C70600 Copper Nickel Tubes undergoes comprehensive inspection before shipment.
| Inspection Item | C68700 Tube | C70600 Tube |
|---|---|---|
| Chemical Composition Analysis | ✓ | ✓ |
| Tensile Strength Test | ✓ | ✓ |
| Yield Strength Test | ✓ | ✓ |
| Elongation Test | ✓ | ✓ |
| Hardness Test | ✓ | ✓ |
| Eddy Current Test | ✓ | ✓ |
| Hydrostatic Pressure Test | Available | Available |
| Dimensional Inspection | ✓ | ✓ |
| Surface Finish Inspection | ✓ | ✓ |
| Straightness Inspection | ✓ | ✓ |
| PMI (Positive Material Identification) | Available | Available |
Inspection Equipment
C68700 Brass Tube Inspection Equipment
| Equipment | Purpose |
|---|---|
| Optical Emission Spectrometer (OES) | Chemical composition analysis |
| Universal Testing Machine | Tensile and mechanical testing |
| Eddy Current Testing Equipment | Detection of surface and internal defects |
| Hydrostatic Pressure Tester | Pressure resistance verification |
| Digital Micrometer & Vernier Caliper | Dimensional inspection |
| Surface Roughness Tester | Surface quality evaluation |
Every order can be supplied with a Mill Test Certificate (EN 10204 3.1). Third-party inspection by SGS, BV, TÜV, or Intertek is also available upon request.
Packaging & Shipping
C68700 Heat Exchanger Tube Packaging
To ensure the tubes arrive safely, all products are packed according to international export standards.
| Packaging Type | Features |
|---|---|
| Plastic End Caps | Protect tube ends from impact and deformation |
| PE Film Wrapping | Prevent scratches during handling |
| Waterproof Plastic Film | Moisture and corrosion protection |
| Woven Bag Packing | Suitable for domestic transportation |
| Export Plywood Cases | Ideal for LCL shipments |
| Wooden Cases | Heavy-duty export packaging |
| Steel Frame Packaging | Suitable for extra-long tubes |
| Customized Labels | Customer logo, PO number, and specifications |
Our Production Lead Time
We maintain sufficient raw material inventory and an efficient production schedule to ensure fast delivery for both standard and customized copper tubes.
| Order Type | Production Lead Time |
|---|---|
| Stock Sizes | 3–7 Days |
| Standard Production | 7–15 Days |
| Customized Sizes | 15–20 Days |
| Large Volume Orders | 20–30 Days |
| U-Bend Tube Processing | 15–25 Days |
SGS Certificate
All C68700 and C70600 copper tubes can be supplied with SGS inspection reports, EN 10204 3.1 Mill Test Certificates, and other required quality documents. Third-party inspections by SGS, BV, TÜV, or Intertek are available before shipment upon customer request.
FAQ
1. What is the main difference between C68700 and C70600?
C68700 is an aluminum brass alloy with excellent thermal conductivity and good seawater corrosion resistance, while C70600 is a 90/10 copper-nickel alloy that offers superior resistance to seawater corrosion, erosion, and biofouling.
2. Which alloy is better for seawater applications?
C70600 is generally the preferred choice for long-term seawater service because it provides outstanding resistance to corrosion and marine fouling.
3. Which material offers better heat transfer performance?
C68700 has higher thermal conductivity than C70600, making it a popular choice for condensers and heat exchangers where heat transfer efficiency is a priority.
4. Are both alloys manufactured according to ASTM B111?
Yes. Both C68700 Aluminum Brass Tubes and C70600 Copper Nickel Tubes are commonly produced in accordance with ASTM B111 specifications.
5. Which alloy is more economical?
C68700 is generally more cost-effective than C70600, while C70600 usually offers a longer service life in aggressive marine environments.
6. Can you manufacture custom tube sizes?
Yes. We can manufacture custom outside diameters, wall thicknesses, lengths, and tolerances based on your drawings or technical requirements.
7. What quality documents do you provide?
We can provide EN 10204 3.1 Mill Test Certificates, chemical composition reports, mechanical property reports, dimensional inspection reports, and third-party inspection reports upon request.
8. Do you support third-party inspection?
Yes. We support inspections by internationally recognized organizations such as SGS, BV, TÜV, and Intertek before shipment.
9. What industries commonly use C68700 and C70600 tubes?
These alloys are widely used in power plants, marine engineering, offshore platforms, desalination plants, petrochemical facilities, HVAC systems, and industrial heat exchangers.
10. How can I choose between C68700 and C70600?
Choose C68700 when high thermal conductivity and cost efficiency are the primary requirements. Choose C70600 when the application involves continuous seawater exposure or requires maximum resistance to corrosion and biofouling.
About us
GNEE is a leading international trader and supplier specializing in a comprehensive range of high-quality copper and copper alloy products. We serve a global clientele across various industries, including HVAC/R, automotive, electronics, construction, and industrial manufacturing.
Our Extensive Product Portfolio
We boast a vast inventory and robust supply chain for virtually all forms of copper products. Our expertise covers:
Copper Seamless Tube / Capillary Copper Tube
Copper Welded Tube / Copper Air Conditioning Tube
Copper Refrigeration Tube / Copper Water Tube
Deoxidized Copper Tube / Copper Coil Tube
Copper Sheets & Plates&Strips：
Copper Strip / Copper Thin Strip
Copper Heavy Duty Strip / Precision Copper Strip
Copper Foil Sheet / Copper Thin Sheet
Copper Thick Plate / Copper Chequered Plate
Copper Shim Stock / Copper Busbar
Copper Round Bar / Copper Square Bar
Copper Hexagon Bar / Copper Flat Bar
Copper Alloy Rod / C11000 Electrolytic Tough Pitch (ETP) Copper Rod
Copper Wire / Bare Copper Wire
Copper Alloy Wire / Oxygen-Free Copper Wire
Copper Profiles / Copper Fittings
Material Grades & International Standards
We provide materials that conform to major international standards to ensure performance, reliability, and global acceptance. Commonly supplied grades and standards include:
Common Grades:
Pure Copper: C10100 (Oxygen-Free Electronic Copper), C10200 (Oxygen-Free Copper), C11000 (Electrolytic Tough Pitch - ETP Copper)
Copper Alloys:
Brass: C26000 (Cartridge Brass), C27200 (Brass), C36000 (Free-Cutting Brass), C38500 (Architectural Bronze)
Phosphor Bronze: C51000
Aluminum Bronze: C60800
Copper-Nickel: C70600 (CuNi 90/10)
Admiralty Brass: C44300
ASTM Standards:
B68 / B68M: Seamless Copper Tube
B75 / B75M: Seamless Copper Pipe
B111 / B111M: Copper and Copper-Alloy Seamless Condenser Tubes and Ferrule Stock
B152 / B152M: Copper Sheet, Strip, Plate, and Rolled Bar
B187 / B187M: Copper Bus Bar, Rod, and Shapes
B301: Free-Cutting Brass Rod
