Have you ever wondered what materials make up the water pipes in your home, the refrigerant lines in your air conditioner, or even the medical gas delivery systems in hospitals? These critical components must meet rigorous standards to ensure our health and safety. This comprehensive guide explores the various types of copper and copper alloy pipes used in building plumbing systems, detailing their manufacturing standards, applications, and unique characteristics.

Pure copper pipes play a vital role in water supply and drainage systems. According to ASTM B42 standards, these pipes are manufactured from five copper alloys (C10200, C10300, C10800, C12000, or C12200) containing at least 99.9% copper with phosphorus content not exceeding 0.04%.

Key specifications:

• Diameter range: 1/8 inch to 12 inches
• Available in standard wall and extra strong wall thicknesses
• Standard length: 12 feet
• Connection methods: threaded, flanged, or brazed

With excellent corrosion resistance and plasticity, these pipes are widely used in water supply, boiler feedwater, and refrigeration systems.

Red brass pipes (85% copper, with lead and iron content ≤0.05%) offer superior corrosion resistance, particularly in water distribution systems. Available in the same size range as pure copper pipes, they share similar connection methods but are particularly suitable for threaded or brazed socket-type fittings in smaller diameters.

This oxygen-free, smooth interior surface tube is ideal for refrigeration, fuel oil, gasoline, or lubricating oil applications. Typically supplied in annealed conditions (O50 or O60), these are custom-order products rather than standard inventory items.

Available in round, square, or rectangular shapes, these tubes serve various engineering applications. Like B68 tubes, they're custom-made to order in different tempers from light-drawn to annealed conditions.

Common in potable water systems, these C12200 alloy tubes (≥99.9% Cu + Ag) come in three wall thickness types:

• Type K (thickest, green stripe)
• Type L (medium, blue stripe)
• Type M (thinnest, red stripe)

With copper content ranging 60-90%, these copper-zinc alloy tubes serve diverse engineering needs. Available in various shapes and tempers, they're typically custom-ordered for specific applications.

This standard establishes baseline requirements for numerous wrought copper product standards including B68, B75, B135, B466 and B743.

• Straight lengths (H58 temper) or coils (O60 temper)
• Special cleaning (≤0.0035 g/ft² residue)
• Blue stripe identification for straight lengths

• H58 temper only
• Similar OD to Schedule 40 pipe but thinner walls
• Gray stripe identification
• 20-foot standard lengths (15-foot for 12-inch)

• H58 temper only
• Yellow stripe identification
• Special drainage fittings per ASME/ANSI B16.23 or B16.29

Made from copper sheet or strip without filler metal, these pipes offer engineering flexibility with multiple alloy choices and tempers, but require careful specification for hydrogen embrittlement-sensitive applications.

Available in various shapes and alloys (62-96% Cu), these are purpose-built for specific engineering applications requiring detailed specifications.

• Only Type K or L (per B88)
• H58 temper only
• C12200 alloy exclusively
• Special cleaning (≤0.0035 g/ft² residue)
• Green (K) or blue (L) stripe identification

• Soft (O60) or hard (H58) tempers
• 60-foot or 100-foot coils (12-foot or 20-foot straight lengths)
• "Type GAS" marking every 18 inches
• Yellow stripe for hard temper straight lengths

Important Note: NFPA 54 (National Fuel Gas Code) does not permit ASTM B837 copper tubes for fuel gas applications. Always consult applicable codes before specification.