Centrifugal Backward-Curved Impeller
Wolter CHEM range fan impellers are designed as single-inlet, single-width (SISW) type. Impellers are made of precision plastic injection-mould parts with cast-in steel hub, which are subsequently mechanically welded. Standard impeller material is PP. Depending on the type of application, different materials such as PA, PC, PVC or PVDF can be processed. If the application calls for high temperature resistance, flame-retardant properties, UV durability or protection against electrostatic discharge, special reinforced compound materials can be used. Each impeller is statically and dynamically balanced in two planes in accordance with Q2.5 of VDI 2060. The impellers are designed for use with taper-bushes and are made of high-grade cast disks guaranteeing solidity at high peripheral speed. For a description of models CHEM 75 and CHEM 90, please refer to our partial catalogue R05.
Fan Base And Support
The supporting steel stands and fan bases are manufactured from heavy gauge mild steel and are hot-dip galvanised or powder coated to provide protection even in the most adverse conditions. Special surface treatments can be applied on request. Fans can be mounted in different discharge positions.
Drive shaft and bearing
All shafts comply to DIN 17210 - C45, they are trued and have a smooth finish. Both shaft ends comply with DIN 748, Sheet 1 and are grooved in accordance with DIN 6885, Sheet 1. A protective coating is applied on the shaft in order to prevent corrosion. If needed, stainless steel shafts can be provided. CHEM 125 to CHEM 400 belt-driven fans are fitted with cast aluminium flanged grooved ball bearings with an acid-proof seal, ensuring minimum vibration.
Drive
Precisely balanced pulleys with tension sleeve are used. All belts comply with ISO 4148. The belt-drive and all other rotating parts are fitted with a protection guard.
Motor
If the application requires, motors of different protection classes can be supplied. On direct-driven fans, B5 flange-type motors are mounted. All motors are totally enclosed and air-cooled. Single-phase motors or motors with non-standard voltages can be supplied upon request
Standard Colours
- All PP fans - PANTONE Warm Grey 1C
- All GRP fans - PANTONE 430
- If required, other colours can be supplied
Ancillary equipment
- Spring anti-vibration mounts
- Condensate drain plug
- Fan and motor support base frame
- Shaft and bearing cover
- Inlet flanges, flexible connections with clamps
- Splinter shield
Options
- variational colouring
- flame-retardant and temperature-resistant material
- Anti-static material
- UV-proof material
Permissible Temperature Range
The temperature of the conveyed gases must not exceed the following limits:
- PVC - 60
- PP - 80
- GRP - 100
- PVDF - 120