Comprehensive Analysis of Negative Pressure Weighing Booth

The negative pressure weighing booth is a special local purification equipment used in pharmaceutical, microbial research and scientific experiments, which provides a vertical unidirectional air flow. Part of the clean air circulates in the work area and part is discharged to the nearby area, so that the work area produces negative pressure. Weighing and packing dust and reagents in the equipment can control the spill and rise of dust and reagents, prevent the inhalation of dust and reagents to the human body, avoid the cross contamination of dust and reagents, and protect the external environment and indoor personnel.

• Main components: primary filter, medium filter, high efficiency filter, uniform flow film, fan, 304 stainless steel structure system, electrical system, automatic control system, pressure detection system, etc.
• Working principle: The air is pressed into the static pressure box by the centrifugal fan in the weighing booth design through the initial effect filter and the medium effect filter, and then the air is diffused to the outlet air surface after the high efficiency filter to blow out, forming a vertical unidirectional air flow to protect the operator and prevent drug pollution. The operating area of the weighing cover discharged 10%-15% of the circulating air to maintain negative pressure to avoid environmental pollution and drug cross-contamination.
• Technical parameters:

1. The airflow velocity is 0.45m/s±20%;
2. Equipped with control system;
3. Wind speed sensor, temperature and humidity sensor is optional;
4. The high efficiency fan module provides clean laminar flow air (measured with 0.3µm particles) to meet clean room requirements with an efficiency of up to 99.995%;
5. Filter module:

• Primary filter - Plate filter G4;
• Medium effect filter - bag filter F8;
• High Efficiency Filter - Liquid tank high efficiency no partition filter H14;

6. 380V power supply.

Suzhou Pharma Machinery has a core technical team composed of industry veterans, specializing in the production of clean room purification equipment, primary efficiency, medium efficiency, and high efficiency filter products. The negative pressure powder weighing booth produced by our company has the following advantages:

• Box selection of high quality SUS304 stainless steel, working area arc design, no dead corners, no dust, easy to clean;
• Top air supply, high efficiency filter efficiency ≥99.99%@0.3μm, operating area purification level is higher than the cleanliness of the room;
• Button control lighting, power;
• A differential pressure meter is installed to monitor the use of the filter;
• Box sampling modular design can be disassembled on-site assembly;
• The return-air orifice plate is fixed by strong magnetic, easy to disassemble and assemble;
• Good unidirectional flow type, dust non-diffusion, good dust trapping effect;
• The isolation methods are soft curtain isolation, plexiglass isolation and other ways;
• Filter level can be selected according to customer needs.

Suzhou Pharma Machinery Co.,Ltd.

2025/03/14

Tia