Fly ash sampler sampling

1. Determination of Sampling

The sampling of fly ash sampler is selected on the flue between the outlet of the air preheater and the inlet of the dust collector. The specific installation location should generally meet the following conditions:

The flue gas temperature is less than 370 ℃;

At the straight pipe outer wall of the horizontal flue, and at a height of 1/3 of the flue from the bottom of the flue; Or at the straight pipe side wall of the vertical flue, and at a distance of 1/3 of the flue thickness from the rear wall of the flue;

There are no obstacles in the flue that affect positive sampling;

The representative parts of smoke flow velocity and dust particles;

There is a space outside the flue for the installation of measuring devices and normal operation.

2. Opening of sampling holes

According to the determined sampling location, remove the insulation layer of the flue after shutdown, and cut a 142mm (width) X232mm (height) rectangular hole on the flue wall for welding the rectangular flange.

3. Welding of canopies, flanges, and brackets

Remove the insulation layer of the flue between the canopy and the installation bracket of the measurement unit according to Figure 5, and then weld the canopy, rectangular flange, measurement unit installation bracket, extended angle iron, support angle iron, and pressure regulating valve installation plate separately (the welding position of the extended angle iron and pressure regulating valve installation plate depends on the on-site situation). When welding, it is necessary to ensure that the distance from the bottom edge of the rain shelter to the rectangular flange is 130mm; 2. The installation surface of the rectangular flange is perpendicular to the ground; 3. The distance from the installation surface of the rectangular flange to the flue wall is 350mm; The distance between the installation bracket of the measuring unit and the rectangular flange is ensured by the welding auxiliary connecting plate.

If the sampling unit is not installed temporarily, the square holes on the rectangular flange should be covered with the flange cover provided by the manufacturer and tightened with screws to ensure the sealing of the flue during boiler operation.

4. Welding of on-site control cabinet installation bracket

The installation bracket of the control unit can be welded between two measuring units or on a steel column near a certain measuring unit according to the on-site conditions. During welding, the height from the edge of the installation bracket to the on-site walkway or platform surface should be about 1.8 meters.

5. Installation of sampling unit

6. Adjust the sampling tube

According to the different positions of the flue installed in the sampling unit, it is necessary to adjust the sampling tube to ensure that the direction of the intake nozzle of the sampling tube is aligned with the direction of the flue gas flow. Adjustment method: 1. Loosen the nut (1), 2. Loosen the long nut, 3. Pull out the sampling tube in an upward direction until the cylindrical pin on the circular flange of the sampling tube is detached from the installation plate. 4. Rotate the sampling tube according to the flow direction of the throat at the installation position, so that the intake nozzle of the sampling tube is facing the direction of the smoke flow. Then insert the cylindrical pin on the circular flange of the sampling tube into the corresponding positioning space on the installation plate. 5. Tighten the long nut, 6. Finally, tighten the nut (1).

7. Installation of measurement units

Installation method: 1. Place the measuring unit on the installation rack and place a spirit level (provided with the equipment) on the measuring unit section; 2. By adjusting the lifting of the four bolts and rods at the bottom of the measuring unit, combined with the stable horizontal movement of the measuring unit, the ash inlet of the measuring unit is concentric with the lower ash outlet of the sampling unit cyclone dust collector. At the same time, the transition pipe component can precisely connect the lower ash outlet of the sampling unit cyclone dust collector and the ash inlet of the measuring unit; 3. Fine tune the 4 rod bolts at the bottom of the measuring unit, while observing the level of the measuring unit, so that the surface of the measuring unit is in a horizontal state; 4. Tighten the nut of the transition pipe component between the measuring unit and the sampling unit cyclone dust collector; 5. Tighten the four parallel nuts of the rod bolts at the bottom of the measuring unit; 6. Tighten the four tie rod bolts at both ends of the bottom of the measuring unit and tighten the nuts; 7. After the installation of the measurement unit is completed, restore the insulation layer and protective iron sheet on the flue wall.