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Tube Leak Monitor

Overview

A tube leak monitor can discover high-pressure steam or water leaks caused by rupture of a boiler furnace wall, super-heater, or reheat combustor at an early stage to keep damage to the customer's boiler to a minimum.

Features

  • Detection of tiny leaks
    A tube leak monitor continuously monitors for tube leaks and can immediately detect tiny leaks that cannot be detected by ear.
  • Reducing boiler downtime and repair expense
    By keeping damage to the tube caused by ruptures to a minimum, you can reduce boiler downtime and repair expense.
  • Allowing an appropriate decision about downtime
    By monitoring the trend of the leak when it occurs, you can make an appropriate decision about the downtime of the unit.
  • Support for a variety of fuel boilers and easy installation
    A various types of fuel boilers are supported. Installing a detector to a boiler is easy.
    The guidelines for the number of sensors to be installed are as follows(Note).
Use Number of units
Electric utility about 10-20
Industry about 10 or less

(Note) Consultation may be required to decide the exact number.

Principle

If the boiler pressure vessel fails and a high-pressure steam or water leak occurs, abnormal noise is generated at or around the rupture. The frequency curve of this noise is different from that of the background noise generated by combustion in the furnace or by the spraying of fuel in the burner. The background noise generally has more power at lower frequencies. Higher frequency noise is generated by high-pressure leaking at ruptures.
Pressure vessel leaks can be detected by monitoring for this higher frequency component.

Principle

The leak detection capability is affected by the following factors:
The level of background noise depends on the structure of the boiler and the positioning of the sensors.
The level of leak noise depends on the direction or angle of the ejected spray as well as the whether or not the spray strikes anything.

Item Specification
Pressure 140kg/cm2
Nozzle diameter 2.0mm
Length to sensor About 10meters

System Configuration

Basic System Configuration

System Configuration

  • Sound detection monitor unit
    This unit enables remote detection of noise in the boiler furnace and leak noise.
  • FFT unit
    This unit is used for frequency analysis of the signals from the amplifiers.
    (FFT: Fast Fourier Transform)
  • Computer system
    The output from each sensor is logged, monitored, and compared with the set background value. This unit generates alarms and displays the status on a monitor.

Monitoring panel

This unit can process the signals from a maximum of 80 sensors. It generates alarms and displays the status. It should be placed in a computer room or similar location.

Monitoring panel

Monitoring panel

Monitoring imageMonitoring image

Sensors

A sensor consists of a sound pipe and an acoustic sensor. Depending on the structure of the boiler, about 20 sensors are installed evenly on the furnace wall and the flue in order to monitor the whole boiler.

Sensors

Specifications

Sensor (F-115)

The specifications of the sensor (F-115) are as follows.

Item Specification
Type Omnidirectional dynamic microphone
Operational temperature range -20 to 60 deg C (Non-cooling type)
Signal cable NVVS(S) 2.0/2C max.500m
Sound pipe 50A straightpipe (Standard size)
Electromagnetic valve Enable AC/DC
Purge air Flow About 450Nl/min a sensor
Temperature max.40 deg C

Monitoring panel

The specifications of the sensor monitoring panel are as follows.

Item Specification
Dimensions (standard type) 2,300mm(H) x 800mm(W) x 800mm(D)
Operational temperature range 0-40 deg C
Amplifier/
Relay Unit
(ARU-100)
Input chanel max.30ch
Output chanel 1ch
Power supply DC24±10%
FFT Unit
(CF-4210A)
Input chanel 1ch
Frequency range DC 20kHz or less
Power supply AC 90-264V(50/60Hz)
Computer Unit CPU Pentium III
OS Windows NT4.0
Power Supply AC 85-132V(50/60Hz)
Display 15inches

Related Products

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