BWG Chart for Condenser Tubes

A BWG chart for condenser tubes provides the wall thickness, inside diameter, and weight per unit length for tubes used in surface condensers, feedwater heaters, and other heat exchange equipment. Condenser tubes typically range from 5/8” to 1-1/2” OD and use BWG gauges 16 to 22 for optimal heat transfer at moderate pressures.

BWG Dimensions for Condenser Tubes

The table below covers the most common condenser tube sizes. OD is the nominal outside diameter; wall thickness follows the BWG gauge system. ID and weight are calculated values.

3/4” OD Condenser Tubes

BWG Gauge	Wall (in)	Wall (mm)	ID (in)	ID (mm)	Weight (lb/ft) CS
14	0.083	2.11	0.584	14.83	0.592
16	0.065	1.65	0.620	15.75	0.476
18	0.049	1.24	0.652	16.56	0.367
20	0.035	0.89	0.680	17.27	0.268
22	0.028	0.71	0.694	17.63	0.216

1” OD Condenser Tubes

BWG Gauge	Wall (in)	Wall (mm)	ID (in)	ID (mm)	Weight (lb/ft) CS
14	0.083	2.11	0.834	21.18	0.814
16	0.065	1.65	0.870	22.10	0.650
18	0.049	1.24	0.902	22.91	0.499
20	0.035	0.89	0.930	23.62	0.361
22	0.028	0.71	0.944	23.98	0.291

When to Use Each BWG Gauge

Condenser tube gauge selection depends on the cooling medium, tube material, and expected service life:

BWG Gauge	Best For	Typical Material
14-16	Cooling water with scaling or fouling tendency	Carbon steel, admiralty brass
18	Standard clean cooling water service	Stainless steel 304/316, copper-nickel
20-22	Clean condensate, closed-loop systems	Titanium, stainless steel

Thinner gauges (BWG 20-22) maximize heat transfer but require clean fluids and regular inspection. Thicker gauges (BWG 14-16) provide corrosion allowance and longer service life in aggressive water chemistries.

Condenser Tube Materials

The most common materials for condenser tubes, along with their ASTM specifications:

Material	ASTM Spec	Seawater	Freshwater	Max Temp
Admiralty brass	B111 C44300	Poor	Good	260°C
90/10 Cu-Ni	B111 C70600	Good	Good	315°C
70/30 Cu-Ni	B111 C71500	Excellent	Good	370°C
SS 304	A213 TP304	Fair	Excellent	538°C
SS 316	A213 TP316	Good	Excellent	538°C
Titanium Gr 2	B338 Gr 2	Excellent	Excellent	315°C

Pro Tip

For power plant condensers using seawater cooling, titanium Grade 2 tubes at BWG 22 (0.028 in) offer the best combination of corrosion resistance and heat transfer. Though the initial cost is higher, the elimination of tube failures and retubing extends the service interval beyond 30 years.

Read the full guide to BWG/SWG tube sizes