Operation; Maintenance - S&P TGT Manual De Instrucciones

4.7 THGT fan motors may be dual purpose for S1 duty cycle and one off emergency high temperature smoke operation, or dedicated
one off emergency high temperature smoke operation, at the stated temperature, after which the complete fan should be replaced.
Manufactures of motors used with THGT fans provide guidance for winding life, and more information can be found in specific motor
O+M Instructions supplied with the fan.
5. Special instructions / operation
5.1 In absence of any specific guidance, installer should assume there will be some air leakage, into or out, of all fans and ductwork. This
may emanate from flange connections, access doors, joints etc. The degree of leakage may increase with higher pressure inside fan
casing or duct.

6. Maintenance

6.1 Maintenance must be carried out by competent personnel and in accordance with applicable International, National and Local
regulations, especially for hazardous areas. Fan equipment should be electrically isolated and locked out before any work started.
6.2 Fan equipment should be regularly cleaned, frequency depending upon service load and application, but no less than every 6 months.
Fan equipment for Dust applications may require more frequent cleaning to ensure safe operation. Cleaning should include all areas
where dust can accumulate in the fan equipment.
6.3 Routine checking of fan equipment should be based on specific working conditions. Special attention should be made to any unusual
sounds, vibration or temperature. If any problems are detected the fan equipment should be stopped immediately and cause
inspected. Frequent attention should be made to bearings, motors and flexible seals.
Vibration sensing, or regular analysis of vibration levels, provides an early indication of potential wear, un-balance, or early warning of
breakdown. Readings should be taken at bearing, 90° to shaft center line, on a clean flat secure surface. If access to motor is not
possible (motor in airstream) then a suitable external location may be identified for comparison.
The basic principle of condition monitoring is to monitor a suitable measurement, so that any upward trend can be detected and taken
as an indication that a problem exists. Thus it is important to:-
A. Identify initial installed vibration level.
B. Select vibration measuring points.
C. Determine the interval for measurements.
D. Establish data recording system.
E. Establish criteria for assessing condition of fan.
This may be particularly useful for ATEX Zone 1 and 21, Equipment Category 2G and 2D, where the risk is greater than Zone 2 or 22,
Equipment Category 3G and 3D.
Guidance to vibration action levels is provided in Annex 4: Table of vibration levels.
Further guidance may be found in ISO 14694 Industrial fans – Specifications for balance quality and vibration levels.
6.4 Re-lubrication of motor bearings, where applicable, should be carried out in accordance with specific motor Instructions provided.
In absence of any specific guidance the amount of grease consumed, and therefore the amount to be added during re-lubrication can
be calculated using:-
(g / h) = 0.005 x D x B
Warning: Do not mix different types of grease.
Warning: Grease can cause skin irritation, eye inflammation. Follow safety procedure.
6.5 The impeller and blades should be regularly checked for damage that could cause imbalance in the moving parts.
6.6 Any sensors or control systems fitted for temperature, vibration, bearing condition etc, must be regularly checked to ensure safe

operation.

6.7 For ATEX impeller clearance "S" between fixed and rotating parts must be inspected to ensure compliance with minimum
values measured in Pre-Start checklist. In absence of any specific data this should be a minimum of 1% of the impeller diameter
"D" and never less than 2mm or more than 20mm, in radial or axial directions.
Warning for ATEX: This running clearance "S" between impeller "D" and duct / case or inlet cone is critical for safe fan
operation. See Annex 5: Typical running clearance for axial fans:-
6.8 Local regulations may prescribe frequency of checking Fans, especially Emergency Ventilation dual purpose (S1+S2) and dedicated
Emergency Ventilation Fans, however, typical checks would be:-
Typical one (1) month check:-
Motor bearings are sufficiently lubricated, all fixings tight, especially impeller locking bolts, support fixings and motor assembly.
Safety guards are correctly affixed.
All rotating parts have free unobstructed movement.
No debris or foreign bodies inside fan or can be drawn into fan.
Fan equipment is clean inside and outside casing.
Dedicated Emergency Ventilation Fans should be run minimum for 15 minutes.
Typical three (3) month check:-
Electrical earth connection tight and safe.
Where: g = quantity of grease (grams)
h = hours of operation (hours)
D = external Diameter of bearing (mm)
B = total width of Bearing (mm)
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