circular diffusers

Publication DIFFUSERS section 2 SEPT 2005 PART E R Air Diffusers supply and exhaust ventilation systems circular diffusers type finish MRA / LD / SE SILVER / 10 / 5 quantity EXAMPLE : control size NOTE: Louvre Dampers are not available for size 30 diffusers introduction installation The MRA range of circular diffusers are high air capacity terminals specifically designed to suit applications such as atria, auditoria or industrial premises. The core position is adjustable on a central screw thread giving conventional horizontal diffusion with exposed duct or ceiling mounted installations, or a progressively adjustable vertical projection setting for spot cooling and heating applications. The diffuser frames and cores are manufactured from aluminium spinnings and incorporate steel adjustment mechanisms and core retainers. MRA diffusers are manufactured in ten standard duct sizes ranging from 150mm to 760mm. The standard diffuser finish is stove enamelled (SE) silver with matt black louvre dampers, but a wide range of paint finishes are also available in either BS or RAL colours. See Part I for details. For ceiling mounted applications, the cores are easily removed to allow the diffuser neck to be rivetted or screw fixed to the stub duct. When MRA/LD’s are installed with flexible ducting, it is advisable to fit a suitable length of sleeve to prevent the damper blades catching the duct reinforcing wire. Otherwise, ensure that there is adequate clearance throughout the blade travel. For ease of commissioning, the damper adjuster can be accessed through the centre cone of the diffuser. ordering details control sizes finish type MRA louvre dampers fitted to the diffuser neck LD. Circular diffusers DESIGN FEATURES 2 B MRA / LD MRA A D o/d E C 32 D/2 F SIZE A B C D E F DIMENSIONS (mm) 6 8 10 12 15 18 21 24 30 340 325 110 152 60 5 457 427 127 203 60 5 569 528 146 254 60 5 680 630 155 305 60 6 851 782 172 381 60 6 1041 934 248 457 60 20 1148 1100 280 533 60 20 1170 1100 280 610 60 20 1420 1300 280 760 100 20 Circular diffusers SPECIFICATIONS dimensions R 3 SIZE SELECTION PARAMETER NECK AIR VELOCITY (m/s) 6 8 10 12 15 18 21 24 30 3.0 3.5 4.0 4.5 5 5.5 6 7 8 10 AIRFLOW RATE (l/s) 54 63 73 81 91 100 109 127 145 181 THROW (m) MIN - MAX 0.6 - 1.2 0.7 - 1.5 0.8 - 1.7 0.9 - 1.9 1.0 - 1.2 1.1 - 2.3 1.25 - 2.5 1.4 - 2.9 1.6 - 3.3 2.0 - 4.1 PROJECTION (m) 3.6 4.0 4.3 4.5 4.7 5.0 5.2 5.7 6.1 6.7 PRESSURE LOSS (Pa) 13 18 24 30 37 44 53 72 94 140 NR LEVEL 16 21 24 28 31 34 40 44 51 AIRFLOW RATE (l/s) 97 114 130 146 162 179 202 224 256 320 THROW (m) MIN - MAX 0.8 - 1.7 0.9 - 1.9 1.1 - 2.2 1.2 - 2.5 1.4 - 2.8 1.5 - 3.0 1.6 - 3.3 1.9 - 3.9 2.2 - 4.4 2.7 - 5.5 PROJECTION (m) 4.7 5.2 5.5 6.0 6.2 6.5 6.7 7.3 7.9 8.8 PRESSURE LOSS (Pa) 11 16 21 26 32 41 50 64 84 130 NR LEVEL 17 21 25 28 31 35 37 41 44 51 AIRFLOW RATE (l/s) 152 177 203 228 252 279 304 355 405 507 THROW (m) MIN - MAX 1.0 - 2.1 1.2 - 2.4 1.4 - 2.8 1.5 - 3.1 1.7 - 3.5 1.9 - 3.8 2.1 - 4.2 2.4 - 4.9 2.7 - 5.5 3.5 - 6.9 PROJECTION (m) 5.8 6.4 6.8 7.3 7.7 8.1 8.5 9.2 10.4 11.4 PRESSURE LOSS (Pa) 9 13 17 21 25 33 39 52 68 110 NR LEVEL 16 22 26 30 33 36 39 44 48 55 AIRFLOW RATE (l/s) 219 255 292 328 366 401 438 511 585 731 THROW (m) MIN - MAX 1.2 - 2.5 1.4 - 2.9 1.6 - 3.3 1.8 - 3.7 2.1 - 4.6 2.3 - 4.6 2.5 - 5.0 2.9 - 5.8 3.3 - 6.7 4.1 - 8.3 PROJECTION (m) 6.9 7.6 8.2 8.8 9.5 10.4 11.4 12.1 12.8 14.2 PRESSURE LOSS (Pa) 9 12 16 21 25 30 37 51 66 102 NR LEVEL 18 23 27 31 35 38 41 46 50 57 AIRFLOW RATE (l/s) 342 399 456 513 570 627 680 798 912 1140 THROW (m) MIN - MAX 1.2 - 2.5 1.8 - 3.6 2.1 - 4.2 2.3 - 4.7 2.6 - 5.2 2.8 - 5.7 3.1 - 6.2 3.6 - 7.3 4.1 - 8.3 5.2 - 10.4 PROJECTION (m) 6.9 9.5 10.9 11.8 12.3 12.8 13.3 14.2 15.2 17.1 PRESSURE LOSS (Pa) 9 10 13 16 20 24 28 39 51 80 NR LEVEL 18 25 29 32 35 38 41 44 50 56 AIRFLOW RATE (l/s) 492 574 656 738 820 902 984 1148 1312 1640

For more information on circular diffusers talk to Brooke Air Sales