Maintenance of carbon deposit faults in XDZ-1-1935 ignition guns for power station boilers

In the combustion system of a power plant boiler, the XDZ-1-1935 high-energy igniter performs the critical task of igniting the combustible gas mixture. Its operating principle is to convert AC power into high-voltage DC power via a step-up transformer, charge a storage capacitor, and ultimately release a high-energy arc spark through a semiconductor nozzle. However, when carbon deposits on the igniter tip reach a thickness of 2mm, the arc may “climb the wall” along the carbon layer, preventing the ignition energy from being released in a concentrated manner and causing ignition failure. After cleaning the carbon deposits, a series of key data tests are required to ensure that the igniter has restored normal performance and avoid secondary failures caused by residual hidden dangers.

I. The Impact of Carbon Deposits on Ignition Gun Performance

The electrode gap of the XDZ-1-1935 igniter is designed to be 2-4mm, and its surface must be kept clean to maintain a stable arc path. When carbon deposits exceed 2mm, the conductivity of the carbonized material significantly changes the arc propagation direction, causing it to deviate from the designed gap, resulting in a “climbing effect.” In this case, the arc energy is dispersed, unable to effectively ignite the gas mixture, resulting in ignition failure. Furthermore, carbon deposits can reduce the electrode’s high-temperature resistance, accelerate the aging of the nozzle material, and shorten the life of the ignition gun.

II. Key Test Data After Cleaning

After cleaning the ignition head, verify the ignition gun’s performance recovery using the following key data:

1. Insulation Resistance Test

The ignition gun’s electrode and housing must have adequate insulation to prevent leakage current from interfering with discharge. Use a megohmmeter to measure the insulation resistance between the electrode and the grounded portion. A normal value should be greater than 10MΩ. If the test value is below the threshold, it may indicate incomplete cleaning or microcracks on the electrode surface, requiring further polishing or nozzle replacement.

2. Electrode Gap Calibration

Carbon deposits may cause electrode position shifting or deformation. Use a vernier caliper to measure the electrode gap and ensure it is restored to the designed value. If the gap is too large, a higher arc voltage is required to break through the air, increasing the risk of ignition failure. If it is too small, a short circuit may result, wasting energy.

3. Output Voltage and Energy Testing

Monitor the ignition gun’s discharge voltage waveform using an oscilloscope or dedicated tester to confirm whether its peak voltage reaches or exceeds 2500V, and verify that the single discharge energy meets the design requirements. Insufficient voltage or energy may indicate decreased energy storage capacitor capacity or deterioration in the discharge tube, requiring replacement of core components.

4. Ignition Frequency Stability

The ignition gun’s discharge frequency directly affects the combustion system’s response speed. Use a frequency meter to measure the actual discharge frequency and ensure it remains stable at 14 ± 2 times/second (reference value). Excessive frequency fluctuations may be related to the crystal oscillator or power supply voltage regulator module in the control circuit, requiring inspection of the circuit board.

5. Arc Path Observation

In a safe environment, observe the arc path during ignition gun discharge using a high-frequency camera or UV light detection equipment. Under normal circumstances, the arc should be concentrated within the electrode gap and have a uniform length. If the arc spreads along the electrode surface or multiple discharge points occur, the electrodes should be cleaned and the insulation coating integrity inspected.

III. Maintenance Recommendations and Long-Term Reliability

To prevent igniter failure due to carbon deposits, a maintenance strategy should be developed based on the operating characteristics of the power plant boiler:

Regular Cleaning Cycle: Set the igniter cleaning cycle based on the fuel’s sulfur content, moisture content, and operating load. If the fuel has a high carbon content, this cleaning cycle can be shortened to every two weeks.

Electrode Surface Treatment: Use emery cloth or a specialized cleaner to remove the oxide layer and fine carbon particles on the electrode surface to ensure conductivity and high-temperature resistance.

Seal Inspection: Regularly inspect the igniter cable connector and housing seal to prevent dust and moisture from intruding into the internal circuitry.

Redundancy Configuration: In critical boiler systems, a dual igniter configuration is recommended to ensure that a backup unit can immediately take over in the event of a failure of the primary igniter.

The performance of the XDZ-1-1935 high-energy igniter is directly related to the safety and efficiency of the power plant boiler. When faced with arc creep caused by carbon deposits, simple cleaning alone is not sufficient to fully restore its functionality. Through systematic testing of key data such as insulation resistance, electrode spacing, and output energy, the health status of the ignition gun can be accurately assessed.

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E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229

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