Pipe Size

When designing your Blutube compressed air system current and future requirements need to be considered for: -how much air is needed? -what pressure is required? -what is the distance from compressor plant to outlets? -does allowance need to be made for future expansion? Select an appropriate pipe size from the chart below allowing for the above factors and ensuring distance of flow is included in the calculations.

Pressure/Flow Table

Maximum recommended air flow for each pipe size. The flow values allow for a 4% pressure drop of applied pressure over 30 metres of pipe. If a maximum pressure drop of 2% is desired, figures listed below should be de-rated by approximately 20%-30%.  The table is calculated using values derived from Mueller’s formula for gaseous flows.

 PRESSURE BLUTUBE 20 BLUTUBE 25 BLUTUBE 32 BLUTUBE 40 BLUTUBE 50 BLUTUBE 63 BLUTUBE 90 BLUTUBE 110 BLUTUBE 160 BAR PSI 1/S CFM 1/S CFM 1/S CFM 1/S CFM 1/S CFM 1/S CFM 1/S CFM 1/S CFM 1/S CFM 6 87 16 34 32 68 62 132 106 225 195 413 387 820 1054 2233 1732 3671 4872 10323 7 102 19 47 38 81 74 157 127 268 233 494 462 980 1258 2667 2068 4383 5816 12326 7.5 109 21 44 41 87 80 170 137 291 252 534 500 1060 1362 2887 2239 4745 6297 13343 8 116 22 47 44 94 87 184 148 313 272 546 539 1142 1467 3109 2412 5111 9782 14372 10 145 29 61 57 122 112 237 191 405 351 744 697 1476 1896 4019 3117 6606 8766 18576 13 189 39 83 78 164 151 321 258 547 475 1006 942 1996 2564 5434 4215 8933 11853 25118

PRESSURE
1 psi = 0.069bar
1 kpa = 0.145psi
1 bar = 100kpa
1 bar = 14.5psi
1 kg/cm2 = 1 bar

FLOW
1 cfm = 0.4719 L/sec
1 I/sec = 2.119 cfm
1 m3/min = 16.67 L/sec
1 m3/min = 35.3147 cfm

APPROXIMATE COMPRESSOR OUTPUT CALCULATION:
1kw x 1.35 = HP x 4 =CFM for Screw compressors.
For Piston compressors some manufacturers quote displacement which needs to be derated by 0.75 to calculate F.A.D. (Free Air Delivery).
Size of receivers shall be calculated as 10 times the flow in l/s optimum or 6 times the flow in l/s minimum.

Fittings

Select from the three ranges of fittings, note that a combination is often used.

Compression ”0” Ring Fittings
Blutube compression fittings are joined by hand and can be removed and reused.

Socket Fusion Weld Fittings
Blutube socket fusion weld fittings are joined using a socket fusion welding tool and results in a fully fused joint of highest integrity.

Electro Fusion Weld Fittings
Blutube electro fusion fittings are assembled by hand and welded via an electro fusion weld machine. These fittings can be assembled and aligned/adjusted prior to welding.  They are ideal for large bore pipework being quick and easy to work with.  This range includes “underpressure air saddles” which are designed for under pressure connections. They eliminate the need to shut down plant and equipment for new connections and are ideally suited to 24 hour operations.

Outlet Requirments

Select outlets to suit your requirements. This includes filters, regulators, lubricators, quick connection couplings, hoses, etc.