Cooling Tower Fan Blade Balancing

The latter would allow the gearbox to rock in a direction parallel to the input shaft.

Cooling tower fan blade balancing.

And the fan has three fiberglass blades. Fan speed motor speed blade pass frequency. No overall vibration level standards are offered by cti. Frequencies present at cooling towers.

Here s the outside and inside. Dynamic balancing cornell balancing offers on site service to perform single and two plane balancing service of all rotating equipment. Where is the 0 65 in sec at 1200 cpm coming from. The fan was balanced to 0 5 mils but there was a high 0 65 in sec at 1200 cpm.

This document is intended to apply specifically to system vibration and mechanical balancing as related to fans and blowers. The equipment we have balanced ranges from small blowers to the largest of cooling tower fans. Thru balancing of the cooling tower fan we were able to reduce the 1x rpm fan vibration levels significantly from 72 mills to 2 5 mills at 330 rpm or from 19 mills to 0 6 mills at 240 rpm. Possible causes were unbalance due to dirty or damaged fan blades or a problem with the gearbox mounting structure.

The vibration levels at both motor fan speed are to be measured at the motor while the vibration levels at the blade pass frequency is to be measured at the fan shroud or stack. The air flow is produced by the fan which is driven by the motor either in direct drive or by gear speed reducer. We also offer shop services balancing motor armatures flywheels and crankshafts. Removal of the heat from the water is done carried out by the flow of the water counter or across to an air flow.

The principles presented however can be generally applied to many rotating components. This document covers impellers while systems see amca standard 204 and ansi standard s2 19 are covered by air. A likely structural natural frequency was identified at 310 cpm. Dynamic balancing of the cooling tower fan.

I m balancing a fan with a speed of 348 rpm and the motor speed is 1800 rpm.