Fans serve the function of forcing or driving air throughout the cooling tower. A factor that many people fail to consider in relation to the efficiency of their cooling tower fans is the effect of air density within a given environment. The cooling tower blades move large volumes of air quietly and efficiently. Because of the larger blades and aforementioned fan area, pedestal fans are much more powerful generally than tower fans which makes them far more useful in larger spaces. This fairly generic pedestal fan is listed at 1854 CFM oh high setting while this popular tower fan is listed as 720CFM on high. A roller arrangement is secured to the tip of the fan blade and upon rotation thereof the honeycomb material is crushed into the proper shape to achieve the desired fan blade tip clearance. Figure 7 highlights the fact that tip clearance effects on fan efficiencies cannot be presented as a single graph for a specific fan. 10. Tighten loose bolts S S S S 16. Luckily, we as a society have developed effective means to get rid of unwanted heat and, in today’s post, we are going to go over one of the components that is essential for the mitigation of heat in industrial applications: axial fans. The fan blades should be securely tightened to the fan hub. We hope that this short blog has helped you gain a better understanding of the variables that can impact the effectiveness of cooling tower fan performance. On the one hand, heat can be a great thing. 4.4 out of 5 stars with 161 reviews. rough conditions of the cooling tower. The Tip Seal provides a substantial increase in fan efficiency at minimum cost for heat exchangers cooling towers Properly installed, Tip Seal will create a ” - ” tip clearance regardless of fan ring irregularities, such as ovalness or eccentricity Tip Seal Installation Manual Page 2 of 6 June 2012 Figure - Tip Seal 9. Each fan blade is factory balanced and precisely measured & matched with accompanying blades before shipping. Considering the majority of the work is done on the outer portion of the fan blade, if this issue is not addressed, there can be a loss of efficiency as high as 15 to 20 percent. •Both cooling tower fans were 5-blade, belt-driven by a 4-pole motor operating on a variable frequency drive. The wide blade design is well suited for low noise operation, delivering superior air flow and pressure capability at reduced speed. ¼ZwB‘ZÝ G`n±ƒ"Š7© @‚[Ùtc88…â ÇÉúÇpÆ$¡Ö¨íÓ³aÍ_Ç3Á°±š7‚0‘Ñvp«‡]…tÝ ûœ‰Gó(ô¦p(œZQ‘)ܑ‡r€']6 :dHŸ¥©ÅÑÌ(+fÖ[UonïXYîn‚³Pß¿L4¯Ì×P™OS1¢ò­jžtÕ\u…cÛØZLÂ:Ivl_¢‚t#E³UNΓë:Âsº•ýØÌÀ~ÍՌÁ~2²Vb¢ äGnµQ´GhWгi÷yDSÎeÿ’Šf˜Èpí&š¡»™Òî…þLìätÓUŒ….ÉXÀà« blade enhancement provides increased performance overcoming tip clearance losses—aiding the movement of air next to the fan cylinder. The effect of tip clearance on fan static efficiency is referred to a tip clearance of 3 mm for a range of volumetric flow rates. Check inside of stack for fan blade rubbing and adjust the tip clearance if necessary. for a 9-ft-diameter fan. Fan efficiency can be undermined by too much tip clearance, poor inlet conditions, and excessive approach and discharge velocities. As the air exits the cooling tower, it will be at a higher pressure than the incoming air due to the work exerted by the fan blades. Blade clearance should be approximately ½” from tip of blade to the fan cowl. EVAPCO is dedicated to designing and manufacturing the highest quality products for the evaporative cooling and industrial refrigeration markets around the globe. Honeywell. To illustrate this point, consider the following example: Test conditions for cooling tower fans usually require a blade tip clearance on a five foot fan blade of about 0.040 inches with a large inlet bell. Cooling tower fan blades pitch angle is varied depending on seasonal requirements.Cooling tower Fan blade Pitch angle is the angle made by the fan with the plane. The configuration of a cooling tower or air cooler can contribute to fan inefficiency. 11. It keeps us warm when it is cold, has allowed us to industrialize more than our ancestors could have ever imagined, and is generally the hallmark of an advanced society. Brochures The Marley HP7000 fan is designed for industrial cooling tower applications, offering distinct advantages over other fan designs. Look at it this way, a cooling tower at sea level is going to have to exert a lot more force than a cooling tower at 5,000 feet above sea level because the air density at sea level is much higher. *Fan blade assemblies are sold as a set to include part #17-01 fan hub, part #17-02 fan blades and part #17-04 u-bolt (if applicable). Below, we have listed a few more of these variables. Featured Video The Marley Flare Tip™ blade enhancement provides increased performance overcoming tip clearance losses, aiding the movement of air next to the fan cylinder. This makes axial fans ideal for low-resistance, high-flow applications such as those needed in industrial cooling applications. Table 3 The operating point (L/G, KaV/L) under the approach of 5 °C, 6 °C, 7 °C and 8 °C, range of 5 °C, and wet bulb temperature of 26°C for blade angle of 67°. Plastic fan blades are lightweight and corrosion resistant for use in harsh environments. Thermal Upgrades for Cooling Tower Efficiency, The Environmental Advantage of Cooling Towers vs Once-Through Cooling Systems, Why FRP is Superior to Wood, Aluminum, Steel, and Concrete. The ratio between motor & fan … On the other hand, heat can be rather detrimental to certain processes. The cooling tower fan was probably 24 to 28 feet diameter and probably ran something like 120 to 130 RPM. High Fan Efficiency – Each stack has a belled inlet and conical, diverging exit for reduced air pressure drop losses and pressure recovery Maximum Fan Performance – Fan stack sections are connected via lap joints or butt flange allowing field adjustment of the stack diameter and control of fan blade tip clearance In addition to these factors, other variables can affect the effectiveness of fan blade efficiency. Tip clearance: Tip clearance is the distance between the blade tip and draft tube. Each set is factory tested and balanced to avoid any vibration issues. Replace splash bars with self-extinguishing PVC cellular film fill. Blade tip clearance: To provide effective cooling and to reduce vibration, fan blade tips should be equal across the plenum, or fan shroud. If you are searching for cooling tower fans, cooling tower fan manufacturers , industrial cooling tower fans, cooling tower fan blades, or cooling tower fans suppliers, Universal Tower Parts can help!. WBT(°C) CWT(°C) HWT(°C) L/G KaV/L GPM CFM 26 31 36 0.530 0.636 17.16 3858.2 Clean R R R R R R R R R R R 17. Check for leakage W S S S 14. The wide chord blade design is well suited for low noise operation as well, delivering superior air flow and pressure capability at reduced speed. Holes in the fan stack beneath the fan cause air to bypass the fill. The density of air is affected by air temperature and altitude at the plane of the fan and can, if not accounted for, can have a serious impact on the effectiveness of a cooling tower. Inspect and repair before each use R ß-?sÁÑ®à-4¤›ï}¡ñ™Ü®ª The tip clearance should be as low as possible for efficient operation. A typical 14 ft. diameter fan with 0.75 inches tip clearance would relate to 0.27 inches or a 28 ft. fan with 1.0 inch tip clearance relates to 0.18 clearance on a 5 ft. diameter fan. Coupling or Drive Shaft Assembly – connect motor to gear box (assumes right angle configuration). Repaint R R R R 18. In the simplest of terms, an axial fan moves air parallel to its axis of rotation. Contact us today and let’s get started! Blade # As Found After Adjustment Pitch must be within +1-0.20 Mount Protractor on Flat bar as base and place it approximately 1" from tip of blade Fan Blade Tracking As Found After Ad'ustment Too much tip clearance allows discharge air to circulate back around blade tips and into the fan inlet. 11. Precision manufacturing ensures reliable operation: When it comes to fan efficiency, every millimetre matters – uniform blade-tip clearance, balancing, weight, width and pitch are Under these ideal conditions, total fan efficiency is typically in the 75 percent to 85 percent range. Continue reading below to learn more. Éø¶=OóÅÜbÿF½`cU$g8šÀ¯'á돼€î_\žõ:ꋔCßÆsÌÎ7#ė˜ZíŸv¬Ï`†s€™Ö>XJÙõ¹ÔËñ1¢E½ü*¨NîEò _š ‚Kë‚Nå î†ìWÓ ¨ç¶CÐÐU98j&^c´’6ˆà7ޓº)k´¥g.j(þü±/º¦µ'ÅÏpnçPpm‡ïu”þµÿ5×kîîºÐ@w–Ô:ßќ–>6(,µNU»iUg4#.H¥!Eõ5½jº¨ÒYëˆ_0²\¹J–~Y|¨_Óø±^ÕuU hÏ{\ËhÍ,ÛÒS (Nat. Each fan blade is factory balanced and precisely measured & matched with accompanying blades before shipping. On old counter-flow cooling towers, replace old spray type nozzles with new square spray ABS practically non-clogging nozzles. Total Efficiency - Fan efficiency based on the total pressure and fan brake horsepower at the same density for standard or actual conditions. Inlet Conditions There are several areas where inlet conditions can seriously affect the fan system. Additionally, axial fans are able to have a wide range of operating characteristics depending upon the shape and width of the individual fan blades. {W˜¬ˆœœ%f듼PÙ°¯´{Á,MíøB½–0iÌÎË!–“ŠiãåÈA‡š ‘6eöý“ó&º™BÍÓЊ ‰c˜ßi9îu$Sí‘P.q Maintaining proper tip clearance is very important. Tip Speed - Peripheral speed of the fan tip expressed in feet per minute. Fan cylinder is venture shaped for enhancing the proper flow of air through the tower. frequencies present at cooling towers: fan speed, motor speed & blade-pass frequency. ... “cooling tower fans” ... Honeywell Oscillating Stand Fan with Double Blades Black. clearance for a 29 -ft-diameter fan or about 0.32in. EVAPCO Inc. is an employee owned manufacturing company with global resources and solutions for worldwide heat transfer applications. To talk about axial fans, it is important to first understand exactly what an axial fan is. rough conditions of the cooling tower. When considering the effectiveness of the axial fan within a cooling tower, it is important to consider the effect of airflow as it enters the tower. Heat is an interesting thing. Basically, this area of the fan blade will become starved for air, rendering the area near the tip of the blade ineffective. In the area around the fan blade, known as the fan ring, air must be collected from all directions and equally accelerated to the velocity at the plane of the fan. Check water level D D 13. If you must move the gearbox to correct a bolt bound situation, be sure to check the blade tip clearance. Deals Clearance Weekly Ad Top Deals RedCard Exclusives Target Circle Offers. Rebalance R R 19. No overall vibration level standards are offered by CTI. The Marley FlareTip™blade enhancement provides increased performance overcoming tip clearance losses—aiding the movement of air next to the fan cylinder. Sometimes this may not be possible to attain, but the consequences should be recognized. Condenser propeller hubs connect the fan blade to the motor drive shaft. Copyright 2019 Industrial Cooling Solutions, Inc. To account for this difference in air density, it is important to adjust the rotational speed of a fan to make sure that the proper volume of air is being pushed through the tower. The amount of clearance has such an effect because it affects the amount of air loss or leakage around the tip, known as the tip vortex. Manufacturer of Cooling Tower Fans - Paharpur HP-3 Cooling Tower FRP Fans, Paharpur HP-4 FRP Fans, Paharpur HP-7S-6 Cooling Tower FRP Fans and Paharpur Type H-3 Multi Blade Aluminium Fan offered by Paharpur Cooling Towers Limited, Kolkata, West Bengal. Additionally, axial fans are able to have a wide range of operating characteristics depending upon the shape and width of the individual fan blades. The less clearance there is around the tip of the fan blades, the less likely it is that the air within the cooling tower will be able to slip around the fan. Turn the fan(s) by hand to insure it turns freely without obstructions. Check fan blade tip clearance S 12. Visually inspect the fan blades. •Spectral data from this fan showed dominant vibration occurring at the fan speed with relatively low levels at both the motor speed and fan blade-pass frequency. Correct excessive and/or uneven fan blade tip clearance and poor fan balance. The newest cooling fans are sleek and thoughtfully-designed, with blade-less versions that are safer for children, and oscillating towers that are better at circulating air around the room. By "excessive" tip clearance, we mean greater than about 0.3% of fan diameter for cooling -tower fans. Cooling Tower Components Cooling Tower Fan Cooling Tower Fan Blades Cooling Tower Fan Motor Cooling Tower Fill Cooling Tower Fill Material Cooling Tower Filtration Cooling Tower FRP Fan Cooling Tower Motor Cooling Tower Nozzles Cooling Tower Pump Drift Eliminator FRP Fan Blades. In addition to these factors, other variables can affect the effectiveness of fan blade efficiency. In Fig. 1, If you would like to learn more about the cooling tower fan options that we offer or you would like to schedule a maintenance check with one of our cooling tower technicians, contact us today and set up an appointment. For many industrial applications, heat can not only cause a decrease in productivity but, if left unaddressed, can actually cause major issues. 161. The optical pickup had been positioned perfectly over the blade tip, while stationary . The Marley FlareTip blade enhancement provides increased performance overcoming tip clearance losses- aiding the movement of air next to the fan cylinder. Optimise cooling tower fan blade angle on a seasonal and/or load basis. Below, we have listed a few more of these variables. Check fiberglass panels for fraying or mat exposure, as these are replacement indicators. 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