FRP Fan stack is also known as Fan ring, Fan Cylinder and Fan Shroud
What is fan stack or fan ring
Fan stack is a boundary around the fan to separate air inlet and air delivery. It has three main components fan cylinder or fans cashing, air inlet or inlet bell, and fan diffuser or velocity recovery cone.
Fan stacks used for the following function
- It maximizes fan efficiency.
- It reduces sound levels near the fan system.
- Stack prevents the reverse running of the fan due to external air interference.
- The Inlet bell provides smooth airflow to the fan.
- The Inlet bell also restricts vena contracta at the fan inlet.
- Fan stack also minimizes discharge air recirculation.
We are a manufacturer of FRP fan stack. Our fan stacks have designed for the smooth surface finish on the working part as well as having superior strength.
In some fan systems, individual components of the stack used alone or with each other.
Fan Stack component
It used to ease smooth air entry to the fan.
Stack Diamater Range Up To
Stack Height range up to
Maya Fan Stack Kay feature
- Our Fan stack enables high velocity-recovery efficiency. Which improves system efficiency and reduced operation cost.
- Fan stacks manufactured from high-quality fibreglass-reinforced plastic.
- Maya fan stack is of double-finish design.
- The smooth inner surface of fan stack drops friction losses. Which provide laminar airflow and reduce turbulence.
- outer surface provides high resistance against climatic conditions.
- High-quality UV protection on both the surface prevents UV rays hamper the stack life.
- Fibre fan stack is reliable yet less in weight. This contributes to improving the cooling tower life.
In some case Fan stack of an extended height required, to promote the discharge of the saturated airstream at higher elevations. It minimizes the effects of recirculation and interference.
The cooling tower fan stack is also known as a cooling tower fan shroud and cooling tower fan cylinder.
Fan Stack is an essential part of the system manufactured from fibre-reinforced plastic (FRP).
Fan Stack is a common term in cooling tower industries for the combination of three components of airflow path it includes-
- An air inlet is also known as fan bell or bell inlet.
- Fan casing the part in which fan operate this is also known as fan cylinder, fan shroud and fan ring.
- The third part of the stack is a velocity recovery cone. It used to recover velocity pressure with the help of a conical divergent at fan exit this also known as fan diffuser.
These stacks have vertical and horizontal ribs which make it very strong to sustain in high wind velocity conditions. We have the in-house capability to develop pattern and mould, so we make any size of fan stacks, and it manufactured in assembled segments.
Fan Air Inlet/ Inlet bell / Fan Bell
In the fan system, the air behind fan come from large volume and have to pass through a small cross-section of the fan casing.
So fan develops negative pressure behind the fan, this pressure is equal in all direction, so it sucks air from every direction.
This air moves toward the fan radially on the smallest distance path. Thus, some of the air move perpendicular to the axis of the fan.
Due to inertia of air coming other than axial direction so resultant air bend toward the centre of cashing and create Vena contracta.
It is like the picture at right having visible vena contracta at a canal.
These phenomena remain much more severe in fans as the velocity of air in fan is much higher, thus it impacts the fan performance.
So to ease the smooth transition of air at fan inlet different shapes utilized to reduce the losses these known as Fan air inlet, inlet bell or fan bell.
This inlet bell provides:-
- Uniform flow at inlet.
- Lower fan noise.
- Reduce Turbulence.
- Reduce pressure drop and horsepower
- And increase airflow at the same fan power.
Types of fan air inlet
Most of the time casing with flange and in some cases an extended piece provided to allow some extra distance for air equalization.
A conical shape added which increase effective inlet area but the disadvantage of flange inlet still exist
It is a most used inlet type and having a very good advantage on system.
It used in cooling tower and mining industries have a very good effect of flow guiding and equalization.
Partner of India’s Largest ACC fan ring supply
At a project of National thermal power corporation (NTPC) which is India’s largest power producer. This handled by the Bharat Heavy Electrical Ltd (BHEL) one of the government giant for EPC project. And ACC of the project supplied by Harbin Air conditioning (HAC)
- The first time NTPC is using ACC for the power plant.
- It is India’s Largest ACC and maybe Asia’s Largest.
- The project having 3 unit of 90 cells.
- Fan size is 36 foot.
Not only supply fan ring, but we also supplied the fan guard for the project.
Fan ring and Guard
Single Projects Supply
It is the boundary which shrouded around the fan and cylindrical in shape, so, it is also known as fan cylinder or fan ring.
It is the most important part which partition +iv and –iv pressure plain.
Back of fan is suction side it is –iv pressure plane of fan and front or delivery side is +iv pressure plain.
The casing should be as accurate in shape as possible because in case of any irregularity it can cause vibration and may develop fatigue on the fan blade.
It is very important to maintain least tip clearance which is a space between the blade tip and casing, as this is the place where two different pressure plane come in contact thus air tends to move back from +iv pressure to –iv pressure side.
So it is always preferable to maintain the smallest and uniform tip clearance and It should be less then 1% of diameter.
Also, the problem of tip clearance become more critical with increasing static pressure in the fan.
With increasing tip clearance efficiency of a low-pressure fan spoiled up to 20 % and high-pressure fan will get stalled and the air starts circulation from this space.
- Heavy-duty robust integrated casing for mining fans.
- FRP cashing for OEM of cooling tower and ACC.
- Fan shroud/ring in combination with inlet bell, delivery diffuser or both.