ROBERTSON VENTILATION INTERNATIONAL
Exhaust Systems
Ultra-Flow Ventilator Ultra-Flow ridge ventilators

Coefficient of Discharge: 0.65
Throat Size: 750mm to 3000mm

The Ultra-Flow Continuous Gravity Ventilator is the most aerodynamically efficient in the RVI range of exhaust ventilators.

The Ultra-Flow provides an energy and cost effective means of air exhaust for severe heat and fume problems. Ideally suited to application in aluminium smelters, steel mills, boiler houses, glass plants and general industrial manufacturing facilities.

Ultra Flow Vents
Typical Cross Section

Ultra-Flow Ventilators
Tainan Incinerator, Taiwan

Design features

  • Coefficient of Discharge: As determined by independent tests is a minimum of 0.65
  • Unobtrusive: Designed to meet architectural requirements of low silhouette and modern design and provide minimum resistance to wind forces.
  • Guiding vanes: Facilitate redirection of exhausted air to provide for a more uniform velocity distribution at top of ventilator opening, allowing for a greater capacity discharge for a given size.
  • Diaphragms: Wind jump diaphragms ensure efficient exhaust even when wind direction parallels the ventilator opening.
  • Welded: frames make for reduced erection costs and lower supporting steel costs, in addition to providing greater overall strength.
  • Materials: Can be supplied in a wide range of cladding materials including Versacor coated sheeting.
  • Acoustics: Can be acoustically treated to suit specific project requirements.
Exhaust Capacity Table: (cubic metres per second per metre run)
Temp. Diff x Eff. Ht.
(T degC x metres)

CLEAR OPENING (mm)
750
1000
1500
2000
2500
3000
30
0.398
0.530

0.795
1.060
1.325
1.590
40
0.459
0.612
0.918
1.224
1.530
1.836
50
0.513
0.684
1.027
1.369
1.711
2.053
60
0.562
0.750
1.125
1.499
1.874
2.249
70
0.607
0.810
1.215
1.620
2.024
2.429
80
0.649
0.866
1.299
1.731
2.164
2.597
90
0.689
0.918
1.377
1.836
2.296
2.755
100
0.726
0.968
1.452
1.936
2.420
2.904
110
0.761
1.015
1.523
2.030
2.538
3.045
120
0.795
1.060
1.590
2.121
2.651
3.181
130
0.828
1.104
1.655
2.207
2.759
3.311
140
0.859
1.145
1.718
2.290
2.863
3.436
150

0.889
1.185
1.778
2.371
2.964
3.556
175
0.960
1.280
1.921
2.561
3.201
3.841
200
1.027
1.369
2.053
2.738
3.422
4.106
250
1.148
1.530
2.296
3.061
3.826
4.591
300
1.257
1.676
2.515
3.353
4.191
5.029
400
1.452
1.936
2.904
3.872
4.839
5.807
500
1.623
2.164
3.246
4.329
5.411
6.493
600
1.778
2.371
3.556
4.742
5.927
7.112
NOTE:
a) The above exhaust capacity table is based upon zero wind velocity. Wind velocity will increase the vent's exhaust capacity.
b) This table is based upon a ratio of free area of inlet openings to exhaust openings of 5:1.0
Dimensions and Mass:
Dimensions (mm)
Approximate Mass
per Linear Metre (kg)
Approximate Mass
Pair of ends (kg)
A
B
C
Versacor
Zincalume
Versacor
Zincalume
750
1100
1900
70
64
116
110
1000
1330
2350
100
92
168
159
1500
1800
3450
124
112
285
269
2000
2270
4550
154
134
450
406
2500
2820
5670
217
200
637
600
3000
3300
6850
290
270
1033
975
NOTE: Mass per metre run related to ventilators with standard 3,000 mm frame spacing.


Specification

The ventilators shall be of the Ultra-Flow Continuous Gravity type as manufactured by HH Robertson and shall be the sizes shown on drawings.

The ventilators shall have a proven Coefficient of Discharge of 0.65, as certified by an independent test authority and shall have an exhaust capacity of ?m3/sec/m/run, based upon ?..°C temperature difference and ?.m effective height, for thermal effect only (ie, zero wind velocity) and shall be sized accordingly.

The ventilators shall be designed to perform as specified regardless of wind velocity or direction.

The ventilators shall be designed to withstand the wind loads generated by a wind speed of ?.m/s in a Terrain Category ?? when centred ?..metres above ground level. (Alternative wind conditions to be provided to suit local code requirements.)

The ventilators shall be watertight under all normal positive pressure conditions.

The ventilators shall be capable of self-cleaning action by the elements with provisions for carrying water and normal wind transported soil material to outside the ventilator.

The ventilators shall have a free exhaust area at their top of two times the throat opening. The total air path through the ventilators is to be equal or larger than the throat opening.

The ventilators shall be equipped with wind jump diaphragms spaced at each structural frame to afford efficient ventilation regardless of wind direction.

The ventilators shall have a cap peak flash and shall have gutters complete with downspouts spaced at not over 6m centres, to drain precipitation from the cap without clogging.

The ventilators shall be equipped with guiding vanes to aid the passage of exhaust air through the ventilator and to aid the distribution of the exhaust air across the outlet opening at the top.

The dampers (where fitted) shall be an integral part of the ventilator and shall form an inverted cone under the cap, protecting the operating mechanism by keeping it out of the exhaust air stream when the dampers are in the open position.

(Method of operation of the dampers to be specified separately and to be of type to suit individual client eg manual, electrical, pneumatic.)

The ventilators shall be constructed of (select one): Versacor Protected Metal, Zincalume - Plain or Painted, Aluminium.

Sheeting profiled to withstand the design wind load above, all flashings shall be of the same material as the sheeting.

Ventilator structural framework shall be hot dip galvanised (alternative or additional coating systems to be specified also eg, high build epoxy).

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Ultra-Flow Ventilators
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