Installation, Maintenance and Operation Manual for COFIMCO B/BR-Series Fans

Transcription

1 Installation, Maintenance and Operation Manual for B/BR - V2.1 - EN July 5, 2011

2 It is recommended that this entire manual be read very intently before proceeding with installing the fan. IMPORTANT: for installations of more than one fan, first, do complete setup of one single fan, and only after ensuring the perfect functioning of this fan (as described in manual), follow same mounting procedure with the rest of fans. ATTENTION: hub and blades of, are patented Cofimco trademark. The content of this manual cannot be copied, reproduced or printed without written authorization from Cofimco S.r.l., and should a falsification occur, Cofimco S.r.l. will protect itself using whatever means consented by law. Copyright c COFIMCO S.r.l., Pombia (NO), ITALY All right reserved.

3 Manufacturer s Declaration Manufacturer: COFIMCO S.r.l. via A.Gramsci 62, Pombia (NO) ITALIA Declares that: each axial fan is manufactured in such a way to be built-in a machine or assembled with other machineries for it to be constituted a machine in accordance with the normative 2006/42/CE; Declares also that: it is not consented to run the fan until the fan, the equipment in which the fan must be built into, or of which must become a component part of, have been declared in accordance with the normative 2006/42/CE and with the national legislation in force.

4 Table of Contents Warranty iv 1 General Informations 1 2 Installation Required tools for assembly Fan rotation and flow direction Inclination of blade axis Installation procedure for Cofimco B/BR-series Fans Hub boss placement to driving shaft Blades installation and pitch angle setting Seal Disk Installation Operating Instructions Prior to start-up operations Post start-up operations Preventive Measures for Maintenance Maintenance and operations Temperature range Possible causes of vibration A Hub Removal 19 B Trouble Shootings 20 C Part List 22 Contacts 24

5 List of Figures 1.1 Type of fan installation Identification tag format Tag example 4267/05/24L/B3RT Necessary tools for installing the blades Blade rotating clockwise Blades axes layout Hub boss with cylindrical bore Hub boss with bushing Blades to hub installation Inclinometer placement Seal disk installation Fan-diameter-change scheme Fastening blocks alignment Vibrations inspection positions A.1 Hub removal C.1 Parts exploded

6 List of Tables 2.1 Bushing screw [7] torque Scew type depending on hub Screw torque blocks - hub (screws (8)(10) standard) Minimum allowed distance blade - closest obstacle (δ min ) Screw torque, bolts [16] fastening blocks - flexy element (standard bolts) Temperature range C.1 Part list standard hub (see Fig.C.1)

7 Warranty COFIMCO S.r.l. guarantees that labour and all material used in the manufacturing of fans are of the highest quality. In case of mechanical breakage within the 1 st year of its functioning or 18 months from when shipped out from our establishments, and our inspectors ascertaining the breakage was caused from defective material and/or poor workmanship, the fan will be repaired or immediately replaced with an identical or equivalent fan free of charge. Repairs or replacements will be F.O.T. from our establishments and will not include transportation or extra labour costs. If ascertained that some outside interference was caused to the fan or the breakage was provoked by an erroneous installation and/or manhandling, Cofimco S.r.l. will cease all warranty. Cost of repairs done without consent from Cofimco S.r.l. will not be accepted. Under no circumstances will Cofimco S.r.l. be responsible for consequential or incidental damage, of any type, a result from manufacturing, selling, installing or use of its product.

8 Chapter 1 General Informations description The stationary adjustable pitch is a remarkable invention because of its simplicity. The hub is a single component made of steel. Blades are made up of an airfoil section in aluminum alloy or fiberglass, fastened to a steel plate through bolting.the steel plate is anchored to the hub through blockers which are bolted to both the steel plate and the hub. The blockers are designed in a way that is possible to modify the fan diameter. Air Flow Air Flow (c) B Type (d) BR Type Figure 1.1: Type of fan installation The are available in two different configurations (see figure 1.1 just as an example): Type B: fans leaning on driving shafts. Type BR: fans suspended on driving shafts.

9 2 Description fan identification numbers All COFIMCO fans are equipped with a tag fixed on the hub to enable a clear and fast identification. The tag format is described on figure 1.2; an example of tag format is shown on figure 1.3. F/T Fan Type (the fan is identified by a serial number): XXXXX XX XXY XXY Hub dimension Hub Type Blade Material: N: Aluminum L: Aluminum with flap F: FRP Blade type Number of blades Fan Diameter (mm) C/R P.O. I After the fan serial number there might be an extra letter, R and/or T, that represent the reverse installation layout and the special tip caps, respectively. COFIMCO reference number. Purchase order number. Item number within the job. A Blade pitch angle in degree. Figure 1.2: Identification tag format COFIMCO S.R.L. - ITALY Via A. Gramsci, POMBIA (NO) F/T 4267/05/24L/B3T C/R 12345/678 P.O. PO I E-1234 A 10.5 BLADE PAT. N HUB PAT. N Figure 1.3: Tag example 4267/05/24L/B3RT Tag shown in example (Fig. 1.3) refers to a fan with a diameter of 4267 mm, made up of 5 blades, each with an Aluminum profile type 24L (with flap) with special T caps,

10 3 hub type B3. Reference Job number 12345/678, customer s purchase order reference number PO123456, Item number within Job E1234 and blade pitch angle ATTENTION: tag referred above is just an example and does not in any way correspond to any data referred to an identification tag of any purchased fan. ATTENTION: data shown on identification tag must always be referred when ordering spare parts. Balancing If not otherwise requested from the beginning, all Cofimco S.r.l. fans are balanced in the following manner: Dynamic fan balancing, with a balance degree of G = 6.3 according to ISO 1940/1, in the case the fan is shipped out already assembled. For a fan dispatched disassembled, the hub is dynamically balanced while the blades are statically balanced so that the reassembled unit correspond to a balance degree of G = 6.3 according to ISO 1940/1. In this case, the blades have the same static moment, therefore they can be placed in any order on the hub (the blades of the same item are interchangeable). Storage As soon as a Cofimco fan is delivered it is very important to administer an accurate inspection in order to verify for possible damages due to transportation. In such cases, present a claim to the transportation company and mention on the claim the relative documents accompanied, such as, bill of lading, insurance certificates (if any), etc. Also, as soon as fan is delivered, please insure that components are exactly what was ordered and delivered. In a case where goods are not in compliance with what ordered, contact Cofimco within 2 weeks of delivery. If a fan is not immediately installed, we recommend that it be kept in a closed dry place, and not place any heavy material whatsoever on the blades. In the case of storage for a long period of time, before putting the product in action, please verify the condition of protective layer of anti-corrosion on all surfaces performed on machines.

11 Chapter 2 Installation This manual refers to, installation conditions can vary in different situations. 2.1 Required tools for assembly For assembling a fan, the following tools are required: Dynamometric spanner (torque wrench fig. 2.1(a)) required for fastening the bolts to a set screw torque. Goniometric level(inclinometer fig. 2.1(b)) required for setting the blade pitch angle to the angle of design, following the procedure described in this chapter. The accuracy of the inclinometer must be at least ±0.5 (max admissible tolerance). (a) Torque wrench (b) Inclinometer Figure 2.1: Necessary tools for installing the blades Upon request COFIMCO S.r.l. has available for sale the necessary tools for installation.

12 2.2 Fan rotation and flow direction Fan rotation and flow direction The direction of fan rotation is correct when air flow moves from pressure side to suction side. In the example seen in figure 2.2 rotation is clockwise, seeing the side that receives air flow; upon request, Cofimco S.r.l. can supply fans with counterclockwise rotation. Axis of rotation Clockwise rotation Blade Axis Air Flow Direction Figure 2.2: Blade rotating clockwise 2.3 Inclination of blade axis Cofimco fan blades may present, respect to the plane perpendicular to the axis of rotation, a small geometric angle in the direction from where the air flow comes from (see fig. 2.3). Because of this angle, the centrifugal force generates a moment of flexure opposite to that generated from trust, reducing stress which the blades can be subject of. It is therefore necessary, while installing, in the presence of this angle that the blade axis be turned toward where the air flow is coming from. Plane of Rotation Axis of Rotation Moment due to Trust Centrifugal Force Blade Axis Inclination Trust Moment due to Centrifugal force Air Flow Figure 2.3: Blades axes layout

13 2.4 Installation procedure for Cofimco B/BR-series Fans Installation procedure for Cofimco B/BR-series Fans After ensuring that all electrical contacts have been disconnected and that the motor can not in any way be started inadvertently, one can proceed with the assembling described herewith Hub boss placement to driving shaft COFIMCO supplies two different types of hub boss: 1.A) Hub boss with cylindrical bore: in this case the hub is directly anchored to the driving shaft, follow figure 2.4 for the installation procedure Figure 2.4: Hub boss with cylindrical bore Coat the driving shaft [1] with a thin layer of grease. If supplied, put the spacer [2] in the driving shaft until it touches the driving shaft s shoulder. Fit the hub [3] through the driving shaft until it touches the driving shaft s shoulder (or the spacer if supplied). Make sure the hub lateral oblique faces placed as on figure 2.4 ( facing down). The driving shaft end, when the hub boss is in contact with its shoulder, should be at least 2 mm inside the hub bore (5 mm are suggested). This to avoid fans vertical displacements when the screw [5] is tightened. Put then the washer [4] to the hub boss and fasten the screw [5] to the driving shaft. NOTE: screw [5] is not supplied by COFIMCO. 1

14 2.4 Installation procedure for Cofimco B/BR-series Fans 7 1.B) Hub boss with bushing: follow figure 2.5 for the installation procedure. ATTENTION: in this case the driving shaft must not be coated with any grease Figure 2.5: Hub boss with bushing Fit the bushing [6] into the driving shaft [1] until it reaches the desired location; the driving shaft end must not be inside the bushing. Install the hub boss to the bushing making sure the screw holes of the two items are aligned. Make sure the hub lateral oblique faces placed as on figure 2.5 ( facing down). When aligned, fasten the hub to the bushing with the screw [7] torque defined on table 2.1. Bushing Type Screw Torque N m Lb ft P Q1 e Q R1 e R S1 e S Table 2.1: Bushing screw [7] torque ATTENTION: do not start the fan with the bore screw (hub with cylindrical bore) or the bushing screws (hub with bushing) fastened incorrectly.

15 2.4 Installation procedure for Cofimco B/BR-series Fans Blades installation and pitch angle setting ATTENTION: before starting with the blades installation clean all the coupling surfaces Blade Axis mm Blade Pitch Angle Adjustment Figure 2.6: Blades to hub installation Proceed with the installation following procedure and taking as a reference figure 2.6: 1. Fit the blade to hub through the fastening devices (screw [8] [10], washers [9] [11]) as shown on figure 2.6. The screws have to be fastened with a screw torque that allow the blade pitch angle setting. It is suggested to apply Loctite 270 or equivalent to lock the screw threads. 2. Place the inclinometer to the blade upper part at 5 mm from the blade ends and perpendicular to blade main axis as shown on figure 2.6. In case of a large profile (the inclinometer length is not enough), it is necessary to use a flat rod long enough to reach the blade leading and trailing edges and then lean the inclinometer on it. See figure 2.7 for a correct placement. Not right placement Right placement Right placement Figure 2.7: Inclinometer placement 3. Rotate the blade until it reaches the requested pitch angle (A ) written on fan identification tag. The maximum admissible tolerance is ±0.5

16 2.4 Installation procedure for Cofimco B/BR-series Fans 9 4. Fasten the screws [8] [10] with the torque wrench. The screw torque depends on bolts classes, this is reported on bolts head. For standard bolt 8.8, 10.9 Class or A4/80 use the screw torques given on table 2.3 depending on the hub type (see table 2.2). NOTE: the hub type is indicated on the identification tag while the bolts class is stamped on screw head and reported in the documentation s part list. Hub Type Screw [8] Screw [10] B1 M14 M12 B3 M16 M14 B6 M20 M20 Table 2.2: Scew type depending on hub ATTENTION: the data regarding the bolts type is reported in the documentation s part list. Screw Type Screw Torque 8.8 Class 10.9 Class A4/80 N m Lb ft N m Lb ft N m Lb ft M M M M Table 2.3: Screw torque blocks - hub (screws (8)(10) standard) Repeat the previous operations for each blade. Before starting the pitch angle setting operation for a new blade, turn the fan until the new blade is located at the same position inside the fan ring as the previous ones. This to compensate any slight vertical deviation from fan axis rotation. ATTENTION: in case of a structure equipped with several fans, before setting blade design pitch angle to all fans, set the pitch angle on one fan only, and follow the operating instructions of chapter 3.

17 2.5 Seal Disk Installation Seal Disk Installation For the installation of seal disk follow the procedure given below taking as reference the figure 2.8. NOTE: B1 hub does not have a seal-disk A 12B 3 3 (a) B3 hub configuration (b) B6 hub configuration Figure 2.8: Seal disk installation 1. Place the seal-disk spacer [12A] or [12B] on the hub B3 or B6, respectively. 2. Place the seal disk [13] on top of the spacer. 3. Fasten the seal-disk to the hub through the M8 screw [15] and washer [14]; it is suggested a screw torque of 22.3 N m (16.5 Lb ft) for screws 8.8 Class, or a screw torque of 14.2 N m (10.5 Lb ft) for screws A4/A2-70. The data regarding the bolts type is reported in the documentation s part list.

18 Chapter 3 Operating Instructions 3.1 Prior to start-up operations 1. Before running the fan be aware that the fastening blocks [17] [18] are anchored to the hub, if there is gap check the screw torque of the screws [8] and [10] (Fig. 2.6). 2. Identify blade static deflection δ s (fan at rest) and the blade dynamic deflection δ d (fan running) from the fan rating sheet. In the case where the static deflection is higher than dynamic one rotate manually the fan for one entire revolution and check that the distance between the blade s lower point and closest obstacle (δ) is greater than distance δ min given on table 3.1 (δ min depends on fan diameter). If static deflection is smaller than dynamic one rotate manually the fan for one entire revolution and check that the distance between the blade s lower point and closest obstacle (δ) satisfy the following equation: δ δ min (T able 3.1) + [δ d δ s ] Fan Diameter (mm) From to Hub Type δ min B B B B B6 250 Table 3.1: Minimum allowed distance blade - closest obstacle (δ min )

19 3.1 Prior to start-up operations 12 ATTENTION: the distance between the blade s lower point and closest obstacle (δ) is valid for wind speed up to 45 m/s. 3. Rotate manually the fan to check that the gap between the blade tip and the fan ring (x) is within the design ratio x/d, where D is the fan diameter. The gap between the blade tip and the fan ring has to be measured along the blade main axis. ATTENTION: the gap measurement between the blade tip and the fan ring has to be done taking into consideration the difference between the static and the dynamic deflection; if the static deflection is bigger than that dynamic, the blade has to be lifted up of a distance equal to δ s δ d ; if the static deflection is smaller than that dynamic, the blade has to be moved down of a distance equal to δ d δ s. NOTE: the static and dynamic deflections are indicated in the fan rating data sheet. In the case where the gap between the blade tip and the fan ring (x) is not that expected, the fan diameter could be reduced acting on fastening blocks [17] and [18] between blade and hub, as shown on figure 3.1, unscrewing bolts [16] Flexy 16 Element Flexy Element Figure 3.1: Fan-diameter-change scheme. ATTENTION: once bolts [16] are unscrewed it necessary to fasten them back at the proper screw torque, for standard bolts use screw torques given on table 3.2 making use exclusively manual tools; therefore the use of any automatic tool is forbidden. ATTENTION: the diameter change has to be the same to all blades and the fastening blocks alignment has to be that showed on figure 3.2. ATTENTION: the data regarding the bolts type is reported in the documentation s part list. 4. Check that blade axes agree with those defined on section Check gear box oil level and belt tension to be as indicated by the manufacturer. 6. Remove all tools from area. 7. Connect motor to power supply.

20 3.1 Prior to start-up operations 13 Blocks Lateral Surface Slotted Block Figure 3.2: Fastening blocks alignment Bolt Type Screw Torque (Hub) 8.8 Class 10.9 Class A4/80 N m Lb ft N m Lb ft N m Lb ft M10 (B1) M12 (B3) M16 (B6) Table 3.2: Screw torque, bolts [16] fastening blocks - flexy element (standard bolts) 8. Start the fan for few second and then switch it off. While the fan is still turning, check that the direction of the blade rotation is correct as defined on section 2.2.

21 3.2 Post start-up operations Post start-up operations 1. Check the power absorption, if excessive, reduce gradually the blade pitch angle until the desired power absorption is reached. If lower than expected, increase gradually the blade pitch angle until the desired power absorption is reached. Update the new pitching angle on the fans of the same structure. NOTE: a pitch angle trim of few degrees, respect to that of design, has to be considered normal. ATTENTION: the power absorption varies inversely to air temperature. 2. Check that vibration level, as in the positions shown on figure 3.3, does not exceed the most restrictive amplitude values between the limits imposed by the normative of the structure where the fan is installed and the limit of 7 mm/s RMS (overall) measured in the frequency range 0 : 50Hz; above 50Hz and until a frequency range that include all the structure forcing frequencies, the limit decrease to 0.5 mm/s RMS (overall). In the case one of the two limits is exceeded, shut the fan down and trace the cause of such an excessive vibration by referring to section 4.3. ATTENTION: the vibration-limit is valid for vibrations that occur along orthogonal axis, hence vibration that remains constant along those axis (it is not valid for rotational vibrations). Figure 3.3: Vibrations inspection positions 3. After one working hour check the hub bolts [8] [10] screw torque. 4. Repeat the bolts [8] [10] screw torque check after 24 working hours from the start-up.

22 Chapter 4 Preventive Measures for Maintenance 4.1 Maintenance and operations A Inspect periodically the overall fan conditions. Inspection time interval depends on fan operating conditions and may vary from a minimum of two weeks to a maximum of six months. During these inspections check the following: screw torque; corrosion of fasteners; general condition of blades surface and flexible elements. It may be necessary to clean the rotor blades in order to ensure the fan proper balance. B Ice formation on the blades of operating fans must be strictly avoided. C The presence of ice on the blades of a still fan must be removed prior to startup to avoid damages. Snow formed on a still fan must be periodically removed, according to the abundance of snow accumulated. D For installations with two-speed motors, when stepping down from high speed to low speed, the motor must be turned off for a suitable duration so that the fan rotation speed has slowed below the low speed full RPM, before the motor is reengaged at the low speed setting. E If the rotation direction has to changed stop the fan completely before changing it. F Check the vibration level in the positions shown in figure 3.3 at regular breaks.

23 4.2 Temperature range 16 G Check periodically the painted parts to seek for any damages due to corrosion. In particular, inside the Cooling Towers, the blade leading edge is subject to heavy corrosion; for the latter case it is recommended an inspection every six months. Restore any corrosion damages, in particular those on blade leading edge. The vibration level, as in the positions shown on figure 3.3, does not exceed the most restrictive amplitude values between the limits imposed by the normative of the structure where the fan is installed and the limit of 7 mm/s RMS (overall) measured in the frequency range 0 : 50Hz; above 50Hz and until a frequency range that include all the structure forcing frequencies, the limit decrease to 0.5 mm/s RMS (overall). In the case one of the two limits is exceeded, shut the fan down and trace the cause of such an excessive vibration by referring to section 4.3. It is suggested to record the vibrations in order to compare it to the previous one. For a correct comparison the measurements have to be done always in the same location and in the same manner. During vibration analysis observe the standard safety procedure, in particular do not get close to a running fan but place the transducers (accelerometer) with a still fan and make the measurements from a safety location. NOTE: the vibration level is a good indicator of the plant conditions. It is therefore opportune to make these measurements frequently (e.g. once a month). ATTENTION: the vibration-limit is valid for vibrations that occur along orthogonal axis, hence vibration that remains constant along those axis (it is not valid for rotational vibrations). 4.2 Temperature range COFIMCO fans are designed to operate at the following temperatures: Min Max - 40 C (-40 F) with standard materials Aluminum blades: C (+ 221 F) Fan running Frp blades: + 80 C (+ 176 F) Fan running C (+221 F) Fan at rest Table 4.1: Temperature range

24 4.3 Possible causes of vibration Possible causes of vibration The actual causes of vibration may vary considerably, some of the most common are the following: A Unbalance of one or more blades: the vibration caused by blade imbalance occurs on fan rotation plane with a frequency equal to the fan RPM and at an amplitude linearly dependent to the degree of imbalance and the square of the rotational speed. B Blade pitch angle not included in the ±0.5 tolerance: this condition causes vibration outside the fan rotation plane at a frequency equal to the fan RPM and at an amplitude which is dependent on the square of the rotational speed. C Blades too close to supports (periodic aerodynamic turbulence): this condition is characterized by vibration outside fan rotation plane at a frequency equal to the product of the number of fan blades and RPM. The amplitude depends upon the extent of the aerodynamic turbulence. D Resonance between one of the possible forcing frequencies of the fan and one or more of the vibration modes of the structure on which it is installed. The main forcing frequencies generated by the fan, normally correspond to the following frequencies: fan RPM; product of fan RPM and the number of blades; product of fan RPM and the number of structural supports capable of generating aerodynamic turbulence (if they are arranged in an axial-geometric manner). E Vibration transmitted by the structure on which the fan is installed: the frequencies of such vibration depend on both the external forcing frequencies and the resonant frequencies of the structure. F Resonance of the blades with one of the possible forcing frequencies: in the vast majority of cases the vibration occurs outside of the blade rotation plane. G Misalignment of the drive shaft: this generates vibration with a frequency that is one or two times the RPM. In most cases the vibration occurs outside the blade rotation plane. H Loosening of blade and/or speed reducer fastening bolts: the fan behavior under these circumstances is totally unpredictable, as it depends on the extent and location of the loosening. I Output-shaft s bearing that is worn out: this condition generates vibration on the blade rotation plane at a frequency equal to the rotor RPM.

25 4.3 Possible causes of vibration 18 J The fan and/or the structure bolts are not tightened: in this case all the bolts have to be tightened. K The draining holes of the blades are obstructed: it is necessary to open them back. L Incorrect hub installation: it is necessary to re-install the hub as described on section 2.4 ATTENTION: the amplitude of the fan vibration is determined by the stiffness of its support. Vibration that would not be critical to a fan supported by a sufficiently rigid structure is amplified by an overly flexible support. This support stiffness may also cause unexpected variations in the resonance frequency of the blades.

26 Appendix A Hub Removal ATTENTION: before removing the hub be aware that the motor electrical sources are disconnected, therefore the motor will not be able to start. The hub removal operation can be done using an hub extractor (see example fig. A.1) not supplied with the fan. The fan hub may be extracted with or with out the blades installed. During removal operation the fan has to be belted in order to avoid its fall after having removed the anchoring bolts. After have removed the hub anchoring screw, place the hub extractor as shown on figure A.1 fitting between the screw [B] and the shaft end a round plate [A] of diameter slightly smaller than hub bore and a thickness of at least 5 mm (this to prevent driving shaft damages). Fasten the extractor to the hub through the screw [B] until the hub is free from the driving shaft. B A (a) B-Extractor (b) Hub removal scheme Figure A.1: Hub removal

27 Appendix B Trouble Shootings Low Air Flow Low Power Absorption TROUBLE SHOOTINGS Situation Possible Causes Possible Solutions System congestion. Clean the entire system Obstacles to the air flow. Static pressure higher than specified one. Blade pitch angle changed. (e. g. bolts [8] [10] not tightened at the right torque). Temperature higher than that of design. Check the real obstacles area and the inlet shape towards the original design. In dry-coolers the minimum free height of the inlet area has to be 1 time the fan diameter at least; this height has to be higher in the case of multiple units in line. Increase blade pitch angle (till 3 deg. after having checked the data sheet selection). Set the right pitch angle and refer to the operation manual to set the right torque of screws and bolts. Increase blade pitch angle (till 3 deg. after having checked the data sheet selection).

28 21 Situation Possible Causes Possible Solutions High power absorption Temperature lower than that of design. Static Pressure lower than that of design. Decrease the blade pitch angle (till 3 deg. after have checked the data sheet selection). Decrease the blade pitch angle (till 3 deg. after have checked the data sheet selection). Screws and bolts of the fan Rubbing between the blades and/or the structure loosened. and the fan ring Fan not centered. Tip clearance too small. Scratch or little damages Contact Cofimco. Thin crack on a blade surface Contact Cofimco. Unbalance of one or more High vibration level blades. Blade pitch angle not included in the 0.5 deg. tolerance. Blades too close to the supports (periodic aerodynamic turbulence). Resonance between one of the possible fan forcing frequencies and one or more of the vibration modes of the structure on which it is installed. Vibration transmitted by the structure on which the fan is installed. Resonance of the blades with one of the possible forcing frequencies. Torque all screws and bolts. Center the fan. Increase the fan ring diameter. Contact Cofimco. Set right blade pitch angle. Contact Cofimco. Contact Cofimco. Contact Cofimco. Contact Cofimco. Misalignment of the drive shaft. Realign the drive shaft. Worn output shaft bearing Contact the supplier. The fan and/or the structure bolts are not tightened The draining holes of the Open the draining holes. blades are obstructed Tighten screws and bolts at the right torque. In case of any problem contact COFIMCO S.r.l. specifying the order number indicated on the fan identification plate.

29 Appendix C Part List ATTENTION: the part list refers to a standard B/BR-Series fan, for special application the actual part list is that included with the fan documentation. Part List Item Description Item Description 1 Driving Shaft 12A Seal disk spacer (if supplied) 2 Spacer (if supplied) 12B Seal disk spacer (if supplied) 3 Hub 13 Seal disk (if supplied) 4 Washer 14 Washer 5 Screw (not supplied by cofimco) 15 Screw 6 Bushing (if supplied) 16 Screw 7 Bushing Screw (If supplied) 17 Upper Block 8 Screw 18 Lower Block 9 Washer 19 FLEXY Element 10 Screw 20 Blade 11 Washer B BR Series fans standard components Table C.1: Part list standard hub (see Fig.C.1)

30 A 12B Figure C.1: Parts exploded

31 Contacts COFIMCO S.r.l. Via A. Gramsci, Pombia (NO) Italy Tel / Fax /