Cts Copper Tubing Sizes

Reference data and engineering information about cts copper tubing sizes for piping systems applications.

ctscoppertubingsizes

Overview

Engineering reference data for Cts Copper Tubing Sizes in piping systems.

Key Formulas

Continuity

$A_1 v_1 = A_2 v_2$

Mass conservation in pipe flow.

Pressure Drop

$\Delta P = f \frac{L}{D} \frac{\rho v^2}{2}$

Darcy-Weisbach equation.

Pipe Area

$A = \frac{\pi D^2}{4}$

Cross-sectional area of a pipe.

Variables

Symbol	Description	Unit
$D$	Pipe diameter	m
$v$	Flow velocity	m/s
$\Delta P$	Pressure drop	Pa
$f$	Friction factor	—

CTS Copper Tubing Data Table

The following table provides the standard Copper Tube Sizes (CTS) for Type K, L, and M tubing used in plumbing across the U.S. and Canada. These dimensions are also commonly used for CPVC piping.

11 rows

Standard CTS Copper Tubing Sizes for Type K, L, and M
Nominal Size	OD(in)	OD(mm)	Type K ID(in)	Type K ID(mm)	Type L ID(in)	Type L ID(mm)	Type M ID(in)	Type M ID(mm)
1/4	0.375	9.5	0.305	7.747	0.315	8.001
3/8	0.5	12.7	0.402	10.211	0.43	10.922	0.45	11.43
1/2	0.625	15.875	0.528	13.411	0.545	13.843	0.569	14.453
5/8	0.75	19.05	0.652	16.561	0.668	16.967	0.69	17.526
3/4	0.875	22.225	0.745	18.923	0.785	19.939	0.811	20.599
1	1.125	28.575	0.995	25.273	1.025	26.035	1.055	26.797
1-1/4	1.375	34.925	1.245	31.623	1.265	32.131	1.291	32.791
1-1/2	1.625	41.275	1.481	37.617	1.505	38.227	1.527	38.786
2	2.125	53.975	1.959	49.759	1.985	50.419	2.009	51.029
2-1/2	2.625	66.675	2.435	61.849	2.465	62.611	2.495	63.373
3	3.125	79.375	2.907	73.838	2.945	74.803	2.981	75.717

Source: Engineering Toolbox

Additional Industry Notes

Global Standards: The CTS (Type K, L, M) system is predominant in North America. In Europe, copper tubes are specified according to BS 2871 (Types X, Y, Z) and EN 1057.
CPVC Compatibility: CPVC (Chlorinated Polyvinyl Chloride) pipes, often used in Schedule 40 and 80, are also manufactured to fit within the CTS dimensional framework, allowing for common fittings.