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Centrifugal Blowers & Exhausters

Centrifugal blowers are custom designed using one or many stages of impellers to move air or gas. These units are the ideal solution for processes requiring uniform pressure, pulse-free flow and oil-free operation. 

Centrifugal blowers are flexible and allow variable flow capabilities without a variable frequency drive (VFD), which is critical for maintaining sufficient amounts of dissolved oxygen at minimum and maximum air requirement levels. Moreover, centrifugal blowers are efficient and contribute to energy and cost-savings due to inlet throttling, custom engineered configurations and no wearing parts. 

No wearing parts means centrifugal blowers are virtually maintenance free. Although routine and preventative maintenance is recommended and performed onsite with nominal operational downtime.

Hoffman & Lamson have the most comprehensive range of centrifugal blowers and the latest technology best suited to maximize productivity and minimize energy costs for operations. Therefore, Hoffman & Lamson is the global leading specialist of centrifugal blowers backed by over 100 years of design, engineering and industry expertise.

The product line for centrifugal blowers consist of: cast or fabricated multistage, high speed turbo and re-manufactured. Centrifugal blower models are similar in focus, but maximize functions specific to each product, such as design or cost.

How Centrifugal Blowers Work

Centrifugal blowers pull vacuum on processes producing positive pressure; thus, economically generating dry, clean air at low pressure resulting in increased production. To create this velocity with a continuous flow of air or gas, centrifugal blowers have a set of internal wheels or impellers. Air or gas is absorbed into the inlet and transferred to the wheel and emitted through the discharge at 90 degrees.

Impellers are individually balanced and assembled onto the shaft, then balanced as a complete assembly. These components are manufactured in cast iron but coatings are available for corrosive gases. Impellers also have incremental vane angles and vary in numbers.

Depending on application requirements, centrifugal blowers are furnished with stages. Each blower comes with 1 to 10 stages and each stage has an impeller. A centrifugal blower with 1 stage, as in one impeller, is specific for low pressure applications whereas 10 stages, as in 10 impellers, is specific for high pressure applications. The amount of resistance for the flow of gas or air determines the required pressure. Higher resistance results in greater number of stages in the centrifugal blower.

Numerous components make up HOFFMAN & LAMSON centrifugal blowers. These components include: baffle rings, balance position, multistage shrouded impellers, flexible coupling, cast housing, labyrinth seal, carbon ring seal or MAX seal (mechanical axial).


Key Components of Centrifugal Blowers Includes:

1. Multiple baffle rings - guide airflow smoothly into the eye of the impeller, dramatically reducing inlet passage losses. When combined with the two-dimensional impeller design increases blower efficiency and pressure/vacuum capability.

2. Balance piston - negates axial force or sucks the rotor back off the bearings, increases rotor bearing life and minimizes leakage of compressed gas.

3. Multistage shrouded impellers - two-dimensional shrouded cast aluminum impellers are balanced individually and keyed onto the shaft. On most blowers, the complete assembly is then balanced to achieve smooth operation with lowest vibration levels in the industry. Rotor assemblies are designed to operate well below the first critical speeds for added reliability. 

4. Flexible coupling - blowers and exhausters connect directly to the power source with a precision aligned flexible coupling. This optimizes power transfer and minimizes bearing loads for longer life. 

5. Cast housing - blower housings are precision machined from high-grade cast iron. Smaller models are cast aluminum. The intermediate blower sections are assembled using high strength steel rods. The blower and its driver are mounted together on a single steel baseplate. This assures long lasting performance and durability.

6. Labyrinth seal - minimizes leakage of gas throughout stages and stops airflow from reversing. 

7. Carbon ring seal/MAX seal (mechanical axial) - for special air and gas applications requiring superior sealing, optional carbon ring seals are available with purge option. 
An innovation in dry seal technology, the MAX seal reduces fugitive emissions by up to 67% when compared to traditional seal options. Ideal for landfill gas and applications handling toxic and explosive gases. Improves safety of your operation while extending bearing life and lowering total cost of ownership.

Hoffman & Lamson Centrifugal Blower Cut-Away

Centrifugal Blower Applications

HOFFMAN & LAMSON centrifugal blowers are manufactured with proven reliability and provide effective, affordable solutions amongst varied application needs. The range of application for centrifugal blowers is ever expanding and includes: air and gas, industrial processing, wastewater treatment, landfill gas and many other air handling applications.  

  • Water and wastewater treatment - centrifugal blowers can be specified for coarse/fine bubble diffuser systems, air scouring/filter backwashing, reactor batch supplemental air, digester gas booster, grit channel mixing and sludge digestion applications.
  • Industrial processing - centrifugal blowers provide air or gas for sulfur recovery, combustion air, process gas boosting, coal mine venting, fluidized bed combustion systems, vapor and gas extraction, composting, sludge incineration, CO2 compression, air knives and printing systems.
  • Engineered vacuum system - centrifugal blowers are used as an exhauster to pick up, convey and capture a myriad of materials ranging from aluminum granules to corn flakes.
  • Other air handling applications 

Centrifugal Blower VS Exhauster

Blowers and exhausters circulate air or gas; however, differ in their process of circulation. Exhausters are the heart of vacuum systems; whereas, blowers channel air or gas in a specific direction. 

A blower is a low pressure, high volume compressor. Blowers are applied to systems that require the machine to provide positive pressure. These units take ambient air or gas from supply and compress the air or gas to produce the required result. 

Exhausters are designed to provide continuous flow and pulse-free air while delivering quiet and clean vacuum. These units are practically maintenance free with only one moving part and no timing gears. Bearings require only occasional greasing and the shaft seals are non- contacting and non-wearing. 

Equipment is tested prior to reaching the customer or end user. This ensures top quality and avoids unforeseeable issues or operational downtime. Therefore, upholding Hoffman & Lamson’s strong reputation as the global leader of engineered vacuum solutions and producing premier quality products efficiently and economically. Hoffman & Lamson offers centrifugal blowers and exhausters for engineered vacuum systems. There are over 100,000 centrifugal blowers and exhausters in operation worldwide.