ASTM B111 UNS C12200 Cu-DHP Copper Tubes

C12200 tube is covered by a wide range of ASTM specifications depending on the application:

Joining Techniques:

Fabrication Techniques:

C12200, phosphorus deoxidised copper, has been made weldable and brazeable by deoxidising with phosphorus. It is widely used as flat products and tubing, especially where it is to be welded or brazed.

Phosphorus significantly reduces the conductivity, which may go as low as 70% IACS, but also raises the softening temperature when work hardened and promotes fine grain size.

C12200 has almost exactly the same mechanical properties as the high purity copper alloys such as C11000. It has excellent deep drawing characteristics and resistance to pitting corrosion when exposed to severe weather and water environments.

C12200 tubes are used in a wide variety of applications, including:

Tubes for hot & cold water, gas & heating installations

Soil & waste pipes

Storage tanks, cisterns & cylinders

Rainwater goods, roofing, fascias, building facades

Evaporators

Heat exchangers

Stills, vats, chemical equipment

Anodes for electroplating baths

C12200 has similar corrosion resistance to C11000. It gives excellent resistance to weathering and very good resistance to many chemicals. It is often used specifically for corrosion resistance.

It is suitable for use with most waters, and can be used underground because it resists soil corrosion. It resists non-oxidising mineral and organic acids, caustic solutions, and saline solutions.

Depending on concentration and specific conditions of exposure, copper generally resists:

Acids: Mineral acids such as hydrochloric and sulphuric acids; organic acids such as acetic acid (including acetates and vinegar), carbolic, citric, formic, oxalic, tartaric and fatty acids; acidic solutions containing sulphur, such as the sulphurous acid and sulphite solutions used in pulp mills.

Alkalies: Fused sodium and potassium hydroxide; concentrated and dilute caustic solutions.

Salt solutions: Aluminium chloride, aluminium sulphate, calcium chloride, copper sulphate, sodium carbonate, sodium nitrate, sodium sulphate, zinc sulphate.

Waters: All potable waters, many industrial and mine waters, seawater and brackish water.

The corrosion resistance of C12200 is NOT adequate for:

Ammonia, amines and ammonium salts

Oxidizing acids such as chromic and nitric acids and their salts

Ferric chloride

Persulphates and perchlorates

Mercury and mercury salts

Q1: What is the difference between C12200 and C11000 copper?
A: C12200 is phosphorus deoxidized copper (0.015-0.040% P). C11000 is electrolytic tough pitch copper (high purity, no deoxidizer). C12200 is weldable and brazeable; C11000 can suffer hydrogen embrittlement when welded. C12200 has slightly lower electrical conductivity (70-90% IACS vs 100%+ for C11000) but similar mechanical properties.

Q2: Why does phosphorus reduce conductivity in C12200?
A: Phosphorus atoms in solid solution scatter electrons, reducing electrical and thermal conductivity. C12200 conductivity ranges from 70-90% IACS compared to 100%+ for pure copper. However, the trade-off is improved weldability and higher softening temperature.

Q3: Can C12200 be used in seawater applications?
A: Yes, with caution. The corrosion resistance table above lists seawater as a suitable medium. However, for high-velocity seawater or long-term immersion, cupronickel alloys (C70600, C71500) are typically preferred. C12200 is more commonly used for fresh water, plumbing, and HVAC.

Q4: What is the maximum operating temperature for C12200?
A: For continuous service, up to about 200°C (400°F). Above this temperature, strength decreases rapidly. Short-term exposure to higher temperatures may be acceptable depending on stress levels. For higher temperature applications, consider other copper alloys or stainless steel.

Q5: How to weld C12200 copper tube?
A: C12200 is weldable by gas shielded arc welding (TIG) and oxy-acetylene welding. Use deoxidized filler rod (ERCu). Clean the tube thoroughly before welding. No preheating is required for thin walls. The phosphorus content prevents hydrogen embrittlement.

Q6: What is the annealing temperature range for C12200?
A: 250-650°C (482-1202°F). The exact temperature depends on the degree of annealing required and prior cold work. Lower temperatures (250-400°C) provide stress relief. Higher temperatures (500-650°C) produce full annealing with recrystallization.

Q7: Is C12200 suitable for underground service?
A: Yes. The corrosion resistance section notes that C12200 resists soil corrosion and can be used underground. However, local soil conditions vary. In aggressive soils, additional protection (wrapping or coating) may be advisable.

Q8: What is the machinability rating of C12200?
A: 20% of free cutting brass. C12200 is gummy and tends to form long chips. Sharp tools, positive rake angles, and appropriate cutting fluids are recommended. For extensive machining, consider leaded copper alloys.

Q9: Which ASTM specifications cover C12200 heat exchanger tubes?
A: ASTM B111 (Seamless Condenser Tubes) is the primary specification. ASTM B395 covers U-bend tubes. ASTM B359 covers tubes with integral fins. ASTM B543 covers welded heat exchanger tubes.

Q10: Does C12200 resist ammonia?
A: No. Ammonia, amines, and ammonium salts are listed as media where C12200 corrosion resistance is NOT adequate. Avoid using C12200 in contact with ammonia or ammonium compounds, which can cause stress corrosion cracking.

Poor packaging destroys even the best copper heat exchanger tube. As a professional copper heat exchanger tube factory serving copper heat exchanger tube USA, Europe, UAE, Saudi Arabia, and India, we follow military-grade export packaging standards to ensure zero damage during sea or air freight.

Our Standard Packaging Process:

For U-Bundle Orders: U tube heat exchanger and U tube bundle heat exchanger are placed in dedicated steel jigs inside the crate to prevent bending radius distortion.

Our Certifications & Compliance:

ASTM B111 pdf and ASME SB111 pdf full traceability.

ISO 9001:2015 quality management system.

Third-party inspection accepted: SGS, BV, Lloyds, or TUV.

Copper heat exchanger tube life expectancy testing reports available upon request.

Get Fast Quote & Logistics Plan