Type D vs Type F Centrifugal Fans: Drive and Bearing Layout

When replacing an industrial centrifugal fan, airflow and pressure are only part of the specification. The shaft, bearings and motor also need to fit the available space. That is where Type D and Type F arrangements differ.

Type D vs Type F: What Changes?

In the A–F arrangement terminology commonly used by Chinese fan manufacturers, both designs use a coupling between the motor and fan shaft. The difference is where the impeller sits relative to the supporting bearings.

A Type D centrifugal fan has an overhung impeller, mounted outside the bearing support span. In a Type F centrifugal fan, the impeller sits between bearings, with support on either side.

What Is the Practical Benefit?

The two layouts give designers different ways to accommodate rotor support, foundations and maintenance access. Type D keeps its supporting bearings to one side of the impeller; Type F supports the impeller between bearing locations. This can matter on a retrofit where the existing foundation, ductwork or service clearance limits the available arrangement.

Neither configuration automatically delivers higher pressure, better efficiency or longer service life. Those depend on the complete fan design and operating conditions.

Compare Ketong's Type D Centrifugal Fan and Type F Centrifugal Fan products.

Hebei Ketong industrial fan manufacturing workshop.

What Should Buyers Check?

Start with the required airflow and pressure at the operating point. Specify the gas temperature, dust loading and any corrosive components. Then check motor position, shaft arrangement, outlet orientation, foundation dimensions and access for bearing inspection and coupling alignment.

For replacement equipment, an existing nameplate, a dimensioned general arrangement drawing and operating data help the manufacturer review the proposed design.

Can a Type F Fan Work as an Induced Draft Fan?

Yes, if the selected fan meets the duty and gas conditions. Type F describes its mechanical arrangement; induced draft describes its role in pulling gas through a boiler, furnace or exhaust system.

See the Type F Induced Draft Fan product page.

Discuss Your Fan Requirements with Ketong

Hebei Ketong offers Type D and Type F centrifugal fan products and reviews project-specific configurations. For a technical enquiry, send your required airflow, pressure, gas conditions, motor supply and available installation drawings.

Send your enquiry to Hebei Ketong.