Roots™ Dresser Rotary Positive Displacement Blowers :: Roots® URAI-J® WHISPAIR Positive Displacement Blowers
ROOTS™ Universal RAI-J™ WHISPAIR™ Rotary Positive Blowers
BASIC BLOWER DESCRIPTION- The ROOTS patented Universal RAI-JTM WHISPAIR blowers are heavy-duty rotary units featuring a compact, sturdy design, engineered for continuous service when operated within speed and vacuum/pressure ratings.
The basic model features a cast-iron casing with a computer-designed cast relief for noise and shock suppression, carburized and ground alloy steel spur timing gears secured to steel shafts with a taper mounting and locknut, and cast-iron involute impellers. Oversized anti-friction bearings are used with a cylindrical roller bearing at the drive shaft to withstand V-belt pull. Detachable rugged steel mounting feet permit easy in-field adaptablility to either vertical or horizontal installation requirements.
The Universal RAI-J® incorporates grease lube on the drive end and splash lube on the gear end.
LOWER AIR PULSATION - Patented WHISPAIRTM blowers operate with up to 40% less pressure pulsation than conventional blowers due to the pressure equalizing effect of the WHISPAIRTM jet design. In conventional blowers, as the impeller opens up to the outlet port, the higher pressure air in the discharge line rapidly expands into the lower pressure pocket formed by the impeller and the blower case. The resulting shock wave strikes the advancing surface of the impeller at near-sonic velocity. Four pressure pulses occur during each revolution, transmitting shock loads to the gear and bearings.
LONGER BEARING LIFE- The pre-pressurization of the low pressure pocket through the WHISPAIR jet cavity smooths the pulsations, resulting in less shock being transmitted through the impellers to the bearings, providing longer bearing life.
LOWER VIBRATION- The reduction in the magnitude of the pressure pulsation results in smoother operation.
LOWER NOISE- The pressure pulses, inherent in the rotary-lobe design, are also the major source of blower noise. The rapid backflow of air into the blower from the discharge line, four times per revolution, results in high noise levels in a conventional blower. The WHISPAIR jet design controls the backflow of air into the blower, reducing noise by approximately 5 dBA vaccum, 3 dB pressure.
| ID | Roots Model # |
Blower Shaft Size (OD") | Blower Inlet/Outlet NPTor Flange | Busines Days to Ship. | Ship. Weight | Price | |
|---|---|---|---|---|---|---|---|
| 403 | Roots URAI-J 33J | 0.750" OD | 2" NPT | 10 | 84 | $1600.00 |
|
| 404 | Roots URAI-J 36J | 0.750" OD | 2.5" NPT | 10 | 112 | $1680.00 |
|
| 405 | Roots URAI-J 45J | 0.875" OD | 2.5" NPT | 10 | 119 | $1960.00 |
|
| 406 | Roots URAI-J 47J | 0.875" OD | 3" NPT | 10 | 138 | $2110.00 |
|
| 407 | Roots URAI-J 56J | 1.125" OD | 4" NPT | 10 | 180 | $2860.00 |
|
| Frame Size | A | A` | B | C | D | D1 | D2 | M | O | O` | P | P` | R | U | DISCH. | AX | WGT |
| 33UJ | 7,25 | 7,25 | 7,63 | 12,13 | 5 | 8,5 | 5 | 6,25 | 12,81 | 10 | 10 | 12,13 | 6,75 | 0,75 | 2.0 NPT | 1,75 | 84 |
| 36UJ | 7,25 | 7,25 | 10 | 14,63 | 5 | 8,5 | 5 | 7,56 | 12,81 | 10,5 | 11 | 12,13 | 6,75 | 0,75 | 2.5 NPT | 1,75 | 112 |
| 45UJ | 8 | 8 | 10 | 15,5 | 6,25 | 10,25 | 6,25 | 8 | 15,06 | 12,25 | 12 | 13,63 | 8,25 | 0,875 | 2.5 NPT | 2 | 119 |
| 47UJ | 8 | 8 | 11,75 | 17,63 | 6,25 | 10,25 | 6,25 | 9,25 | 15,06 | 12,25 | 12 | 13,63 | 8,25 | 0,875 | 3.0 NPT | 2 | 138 |
| 56UJ | 10,5 | 10,5 | 11 | 17,5 | 6,25 | 11,25 | 6,75 | 9,19 | 17,38 | 14 | 14 | 17,25 | 8,75 | 1,125 | 4.0 NPT | 2,5 | 190 |
Positive Displacement Blowers - Roots® URAI® WHISPAIR Pressure Performance Table
| Frame Size | Speed RPM | 4 PSI CFM | 4 PSI BHP | 5 PSI CFM | 5 PSI BHP | 6 PSI CFM | 6 PSI BHP | 7 PSI CFM | 7 PSI BHP | 8 PSI CFM | 8 PSI BHP | 9 PSI CFM | 9 PSI BHP | 10 PSI CFM | 10 PSI BHP | 12 PSI CFM | 12 PSI BHP | 13 PSI CFM | 13 PSI BHP |
| 33UJ | 1750.00 | 75.00 | 1.00 | 71.00 | 2.00 | 67.00 | 2.00 | 64.00 | 3.00 | 61.00 | 3.00 | 58.00 | 4.00 | 56.00 | 4.00 | 51.00 | 5.00 | ||
| 33UJ | 2950.00 | 149.00 | 3.00 | 145.00 | 4.00 | 141.00 | 4.00 | 138.00 | 5.00 | 135.00 | 6.00 | 132.00 | 7.00 | 130.00 | 8.00 | 125.00 | 9.00 | ||
| 33UJ | 3550.00 | 186.00 | 4.00 | 182.00 | 5.00 | 178.00 | 6.00 | 175.00 | 6.00 | 172.00 | 7.00 | 169.00 | 8.00 | 167.00 | 9.00 | 162.00 | 11.00 | ||
| 36UJ | 1750.00 | 132.00 | 3.00 | 126.00 | 3.00 | 121.00 | 4.00 | 117.00 | 5.00 | ||||||||||
| 36UJ | 2950.00 | 254.00 | 5.00 | 249.00 | 6.00 | 244.00 | 8.00 | 239.00 | 9.00 | ||||||||||
| 36UJ | 3550.00 | 316.00 | 6.00 | 310.00 | 8.00 | 305.00 | 9.00 | 300.00 | 11.00 | ||||||||||
| 45UJ | 1750.00 | 161.00 | 3.00 | 155.00 | 4.00 | 150.00 | 5.00 | 145.00 | 6.00 | 140.00 | 7.00 | 136.00 | 8.00 | 132.00 | 9.00 | ||||
| 45UJ | 2950.00 | 306.00 | 6.00 | 300.00 | 8.00 | 295.00 | 9.00 | 290.00 | 11.00 | 285.00 | 12.00 | 281.00 | 14.00 | 277.00 | 16.00 | ||||
| 45UJ | 3550.00 | 379.00 | 8.00 | 373.00 | 10.00 | 368.00 | 12.00 | 363.00 | 13.00 | 358.00 | 15.00 | 354.00 | 17.00 | 349.00 | 19.00 | ||||
| 47UJ | 1750.00 | 215.00 | 5.00 | 208.00 | 6.00 | 201.00 | 7.00 | 195.00 | 8.00 | ||||||||||
| 47UJ | 2950.00 | 407.00 | 8.00 | 399.00 | 10.00 | 392.00 | 12.00 | 386.00 | 14.00 | ||||||||||
| 47UJ | 3550.00 | 502.00 | 10.00 | 495.00 | 13.00 | 488.00 | 15.00 | 482.00 | 18.00 | ||||||||||
| 56UJ | 1170.00 | 196.00 | 4.00 | 188.00 | 5.00 | 182.00 | 6.00 | 175.00 | 8.00 | 170.00 | 9.00 | 164.00 | 10.00 | 159.00 | 11.00 | 150.00 | 13.00 | ||
| 56UJ | 1750.00 | 324.00 | 7.00 | 316.00 | 8.00 | 310.00 | 10.00 | 304.00 | 12.00 | 298.00 | 13.00 | 292.00 | 15.00 | 287.00 | 17.00 | 278.00 | 20.00 | 273.00 | 22.00 |
| 56UJ | 2850.00 | 567.00 | 12.00 | 560.00 | 15.00 | 553.00 | 17.00 | 547.00 | 20.00 | 541.00 | 23.00 | 536.00 | 26.00 | 530.00 | 28.00 | 521.00 | 34.00 | 517.00 | 37.00 |
Positive Displacement Blowers - Roots® URAI® WHISPAIR Vacuum Performance Chart
| Frame Size | Speed RPM | MAX VACUUM HG " | MAX VACUUM CFM | MAX VACUUM BHP |
| 33UJ | 1750.00 | 13.00 | 53.00 | 3.00 |
| 33UJ | 2950.00 | 15.00 | 119.00 | 5.00 |
| 33UJ | 3550.00 | 15.00 | 156.00 | 7.00 |
| 36UJ | 1750.00 | 14.00 | 95.00 | 5.00 |
| 36UJ | 2950.00 | 15.00 | 212.00 | 9.00 |
| 36UJ | 3550.00 | 15.00 | 273.00 | 11.00 |
| 45UJ | 1750.00 | 14.00 | 121.00 | 6.00 |
| 45UJ | 2950.00 | 16.00 | 253.00 | 12.00 |
| 45UJ | 3550.00 | 16.00 | 326.00 | 15.00 |
| 47UJ | 1750.00 | 14.00 | 165.00 | 8.00 |
| 47UJ | 2950.00 | 15.00 | 348.00 | 15.00 |
| 47UJ | 3550.00 | 15.00 | 444.00 | 18.00 |
| 56UJ | 1170.00 | 14.00 | 146.00 | 7.00 |
| 56UJ | 1750.00 | 15.00 | 266.00 | 12.00 |
| 56UJ | 2850.00 | 16.00 | 501.00 | 22.00 |
