Selection or customization of negative pressure weighing room to consider

This negative pressure weighing chamber can be selected according to the actual size of the actual use or customization, in the selection or customization to consider the following issues:
1. Determine the area of ​​the operating area
Specific operating area area to be based on the actual situation may be, for example, there are several operators, put a few balances, put a few barrels, barrel size, cutting methods, etc., should also take into account the height of the workshop.

2. Temperature and humidity control methods and requirements
Temperature and humidity parameters according to process requirements, generally no special requirements do not control. If the operating area of ​​the area> 3 m2 and continuous use more than 3 h, the design should consider the cooling control. Cooling control usually has two ways: water coil cooling and air cooling cooling.

3. Illumination, noise requirements
In the selection, the negative pressure protection device illumination is usually not less than 300 Lx; noise is usually not more than 75 dB.

4. Cleanliness requirements
Often some users believe that the weighing protection device operating area is laminar, so cleanliness to reach A level. In fact, the regulations clear the region's air cleanliness level and the background room can be consistent.

5. High efficiency filter sealing and integrity testing
The negative pressure protection device is usually equipped with a DOP detection port for filter integrity testing.

6. Laminar wind speed and centrifugal fan requirements
The wind speed design of the negative pressure protection device is consistent with other Class A laminar flow, ie 0.45 m / s ± 20%, which is normally designed to be manual or automatically adjustable (on-line wind speed monitoring) according to the actual situation. If the use of online wind speed monitoring, with a wind speed sensor. Centrifugal fan can control the wind speed, when the wind speed does not meet the requirements, through the wind speed sensor sensor to send to the inverter, the inverter to adjust the motor frequency. When the fan is abnormal, it can be displayed through the filter differential and touch screen.

7. Early, medium and high efficiency filter and fan monitoring and alarm
For the use of early, medium and high efficiency filter and fan operation to monitor and record, can be equipped with four differential pressure sensor: control indoor and outdoor negative pressure, junior high efficiency, efficient air supply resistance, exhaust efficient resistance. At the same time, it should be on the flow membrane and early, medium and high efficiency filter resistance can be displayed on the touch screen. Differential pressure sensor using PLC controller on-line dynamic control Weighing chamber working status, can be stored, printed, display, deviation from the set working state can be automatically corrected, calibration deviation from the alarm.

8. other
Selection should take into account the actual plant site size restrictions, especially the width should usually add 650 ~ 800 mm (mechanical area) size. In the design of the new plant, should be considered to the device configuration machinery room, in order to facilitate routine maintenance.