JIS H3300 C1220T ASTM B88 Standards

Copper Tubes and Copper Coils are made in accordance to JIS H3300 C1220T, ASTM B88 Standards. B88 Standards tubes are also called Type K copper pipes and Type L Copper pipes. JIS H3300 C1220T Copper tubes are suitable for water works and ASTM B88 copper tubes are suitable for air conditioning and refrigeration field service.
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Types K and L tubes are designated by ASTM nominal sizes, with the actual outside diameter (OD) 1/8 inch larger than the nominal size designation. The difference between Type K and Type L tubes are different wall thicknesses. Type K tubes has thicker walls than Type L tubes for any given diameter.