The main fault of burner fan and its cause analysis

The main structural components of the burner fan are impeller, casing, air inlet, bracket, motor, pulley, coupling, silencer, transmission parts (bearings) and so on. Improper installation and improper maintenance can potentially shorten the service life of the burner fan.

Common faults:

1. Wear of transmission parts

Transmission parts wear is a common problem of fans, including various shaft, roller, reducer, motor, pump and other bearing position, bearing seat, keyway and thread, etc. Traditional repair welding machining method is easy to cause material damage, leading to component deformation or fracture, which has great limitations. Brush plating and spraying remachining methods often need external assistance, not only the repair cycle is long, the cost is high, and because of the repair material or metal material, can not fundamentally solve the cause of wear (metal impact resistance and degradation is poor); Moreover, many parts can only be scrapped and replaced, which greatly increases the production cost and inventory spare parts, making the good resource advantage of enterprises idle and wasted.

2. Vibration fault

The fan and motor are connected by a coupling to transmit motion and torque. Misalignment is the most common fault of the fan, and 60% of the fault of the fan is related to misalignment. The fault of the fan refers to the tilt or deviation degree of the axis line and bearing center line of the rotor of the fan and motor. The misalignment of the fan rotor can be divided into coupling misalignment and bearing misalignment. Of the fan rotor system fault, in the rotation process will produce a series of the dynamic effect of adverse to the equipment operation, cause coupling of deflection and bearing wear, the oil film of steady state and axis deflection, etc., not only make the rotor shaft and bearing position and bearing working condition changed, at the same time reduce the natural frequency of the axis, the rotor bearing and the bearing of the additional force lead to abnormal vibration of the fan and bearing early damage, damage is great. For the fan misalignment fault, you can use the laser alignment instrument to solve, convenient and fast.

Cause analysis,

1. Installation reasons:

Improper installation of machinery, parts dislocation, large pre-load

Poor alignment of shafting

The geometrical parameters of the machine (such as fit clearance, interference and relative position) are improperly adjusted

The dynamic characteristics and installation precision of the machine are changed when the pipeline is under great stress

The rotor is placed improperly for a long time, which changes the dynamic balance precision

Not in accordance with the rules of maintenance, damage the original machine with the nature and precision

2. Improper operation:

Process parameters (such as medium temperature, pressure, flow, load, etc.) deviate from the design value, and the machine runs under abnormal conditions

The operation of the machine under overspeed and overload has changed its working characteristics

The operating point approaches or falls into the critical speed zone

Poor lubrication or cooling

Partial damage or scaling of rotor

Improper operation in the start-stop or lift-speed process, insufficient warm-up, uneven thermal expansion or too long stay in the critical area

3. Equipment degradation:

In the long run, the deflection of the rotor increases or the dynamic balance deteriorates

Partial damage, shedding or cracking of the rotor

Wear, pitting, or corrosion of parts

The bearing surface degrades, resulting in interference deficiency or looseness, which destroys the mating properties and precision

The settlement of the foundation of the machine is uneven, and the shell of the machine is deformed