Process Cooling Fans
Process cooling refers to removing heat to maintain or control appropriate temperature levels in an industrial system. Nearly all manufacturing processes produce some amount of excess heat, whether through process heating or through the friction of moving machinery.
In these applications, centrifugal fans provide the essential pressures and airflow required to change the temperature of the process air or other medium or material from higher to lower. They tend to sit between other applications in the process, like a combustion burner and an SCR System, or between a rotary dryer and a cyclone separator, adding ambient air to cool the exhaust stream. Your required pressure and airflow will dictate your process cooling fan selection and specifications.
Primary Industries for Process Cooling Applications
Process cooling fan applications are found across industries. However, because they are often used to remove heat between process applications like dryers, burners, and boilers, any or all of these industries may require process cooling:
- Agricultural Processing
- Automotive OEM
- Building Materials
- Chemical Processing
- Dairy Processing
- Food Processing
- Galvanizing Metals
- Glass Manufacturing
- Metals & Mining
- Oil & Gas
- Paint & Surface Coatings
- Petrochemical Plants
- Power Plants
- Printing, Packaging & Labeling
- Pulp & Paper
- Rubber & Plastics
- Semiconductor & Electronics
- Wastewater Treatment
Process Cooling Fan Selection & Specification
Process cooling fans (blowers) most often sit outside the gas stream and inject cooling ambient air at volumes and pressures that are dictated by the specific application.
Typical Process Cooling Fan Types
- Backward Curved (BCHS, BCLS, BCMS)
- Backward Inclined (BIHS)
- High Pressure Blowers
- Plug Fan
Fan Arrangements indicate how the motors mount to and drive the fans. The specification will depend on your application and the fan(s) selected. Here are two examples:
Arrangement 1 – Belt Drive with an overhung impeller. The fan and motor mount separately to a unitary base.
Arrangement 8 – Direct Drive with an overhung impeller. The fan shaft is directly coupled to the motor shaft with a flexible coupling.
Accessories & Design
“Pushing” ambient air for process cooling involves less wear-and-tear on the fan than dirty and hot airstreams. While ambient air may not be as hard on the fan compared to more extreme conditions, fan/system imbalance and excessive vibration can still be a problem. It’s critical that fan vibration levels are monitored and addressed if they exceed recommended levels.
Proximity to high temperatures and possibly corrosive gasses may also require customizing process cooling fans for these extremes, including their temperature variations. Additionally, in many cooling applications, two fans are required, either for redundancy or for additional pressure.
Here are just some of the accessories and features you may see in process cooling fan applications:
- 304/316 Stainless Steel
- SSPC-SP10 bead blast surface preparation
- Food-grade Teflon shaft seal
- Stainless BFM fittings
- Double-width housing for higher airflow capacity
- Bearings and motors that are isolated from the process
- Shaft seals with ceramic felt elements
- Flex Connectors to accommodate shifting during rapid temperature change
- Spring Vibration Isolators to protect the fan from excessive vibration
- Inlet Silencer for noise control on the fan inlet
- Inlet Vane Damper, Variable Frequency Drive (VFD), Outlet Damper, or a combination for volume and pressure control
- Inlet Filter or Screen to keep the airstream clean and avoid damaging the dampers
- Inlet Box if space is limited for the ductwork
- Vibration and temperature sensors to monitor bearing and fan health and prevent unplanned outages
- Split Housing for easier maintenance access to the fan wheel and shaft
- Proper installation and maintenance to ensure safe startup and operations