Workshop Floor Plan Reference Guide - Ventilation

Before selecting a suitable ventilation system, the manager should fully study the radiation source used, the behavior of the employees, and the air flow in the area. Sometimes managers should also seek assistance from experienced professional ventilation engineers to collect relevant data.

Local Exhaust System The common local exhaust system consists of five parts: fans, waste storage, ducts, air cleaners, and chimneys. The purpose of the local exhaust system is to catch the emitted pollutants at or near the radiation source to prevent it from spreading in the workspace.

Fan Selection In order to select the right fan for the ventilation system, HVAC engineers would recommend making a choice after considering the following factors:

* exhaust volume;
* Fan static pressure;
* The type and concentration of contaminants in the air (they affect the type of fan and the materials used), and an important limiting factor is the fan noise.

After getting this information, you can select the most suitable fan. Although the differences between the fans are large, they can be roughly classified into two major categories: axial fans and centrifugal fans.

For detailed instructions, please refer to "ACGIH Industrial Fan Guide". Source: ACGIH “National Institute of Industrial Hygiene”. Address: 1330 Kemper Meadow Street, Cincinnati, OH 45240, USA, fax 513-542-3355

Waste storage Waste storage captures, contains, or accepts contaminants from sources of radiation. In order to minimize the flow of air, the operation should be as tight as possible, such as the use of ventilation hoods, insulation panels or curtains. They can isolate pollutants and reduce air circulation.

When using waste storage, it should be as close as possible to the source of the contamination. Reducing the production of pollutants or the release of pollutants from the process means reducing the investment in ventilation equipment.

The role of most ventilation equipment is to reduce the inhalation of employee pollutants. Therefore, the waste storage should be installed in an area away from the workers' breathing space.

Since the volatile matter is heavier than air, it always sinks near the floor of the plant, so the waste storage can be installed here. A small amount of contaminants in the air (1000 PPM means 1000 parts of contaminants plus 999,000 parts of air) have a density close to that of the air, and the random air flow will carry the contaminants quickly spreading in the air. Waste storage must be designed in accordance with the standards in the ACGIH Industrial Ventilation Guidelines.

The duct air flows in the duct at a speed of 2000-6000 feet per minute. The catheter can be made of gold plated material, fiberglass, plastic or cement. The type, length, air flow rate, air density, and diameter of the catheter are different for the catheter, resulting in different frictional losses.

The air cleaner air cleaner is designed according to the required degree of cleanliness. Regular maintenance can improve the performance of air cleaners and reduce the harm to employees. Different types of air cleaners can eliminate:

* Particles (as well as precipitation cyclones, etc.)
* Gas ​​and water vapor (and detergents).

The chimney stack discharges the exhaust gas into the surrounding environment. The net removal rate varies according to the volume of exhaust gas, wind speed, wind direction, temperature, and location. When installing the chimney, please note:

* Maintain a certain height (at least 10 feet above the adjacent roof or air intake);
* Installed in the air inlet under the tuyere;
* The exhaust speed is at least 1.4 times the wind speed;
* Keep away from air intakes as much as possible (50 feet recommended)
*10 feet above the roof to avoid backflow;
* Cannot use rain cap if the distance from the air intake is less than 10 feet

General exhaust (dilution) ventilators General exhaust ventilation, also known as dilution ventilation. It does not absorb contaminants at the source and discharge them. Instead, they allow contaminants to enter the workplace air and dilute them to acceptable levels (eg, to meet the PEL—the limit for allowing human activity—or below it). Dilution systems are commonly used to control evaporable liquids.

The supplemental air system exhaust ventilation system requires replacement of exhaust gas. Supplemental air can be naturally obtained from the surrounding environment by air pressure, such as open doors and windows, skylights and adjacent spaces, as well as wall joints, window joints, door joints, top louvers, etc. (Not feasible ).

Supplementary air can also be obtained through specialized air supplement systems. In summary, exhaust systems and specialized air supplement systems are interrelated. Reasons for designing and installing dedicated air replenishment systems are:

* Avoid high-speed airflow through cracks, door seams and window seams on walls;
* Avoid creating pressure differences at doors, exits and windows;
* Make an adjustment to the supplemental air.

If there is no supplemental air, a slight negative air pressure will be generated in the room, affecting the working efficiency of the exhaust system.

HVAC
HVAC (Heating, Ventilating, and Air Conditioning) is a common term that also includes cooling, moisturizing, drying, and other air treatments that make the air comfortable and beneficial to the human body. HVAC can also be used to control ozone and carbon dioxide concentrations.

Air conditioning includes every step of air conditioning of working and living spaces: air and hot air, humidity control, and air cleaning. Historically, air conditioning was mainly used in the industrial field to improve and protect machinery and equipment and production processes. The space where air conditioners are used for personnel activities is now common. Although the initial installation cost of the air-conditioning system is high, the annual cost only accounts for 1%-5% of the total annual production cost, but it can increase the labor force of employees, reduce the absenteeism rate, improve the health level, reduce indoor maintenance, and make air conditioning very Good economy.

Mechanical air control systems are simple and complex, but all are based on the user's purpose for ventilation, temperature control, humidity control, and air quality control. The single unit can be used in this area, and the central unit can serve multiple spaces.

HVAC engineers always like to install air control systems in one place for control. However, the installation and maintenance costs are directly related to the number of locations. Some systems require a separate control area.

The acquisition and circulation of supplemental air is critical to the proper functioning of the system. The correct volume of air should be delivered to the designated space. To prevent interruption of the exhaust gas, a recorder should be installed to enhance dilution efficiency.

Planning and design of air control systems should consider unit flow, temperature, humidity, and air quality. The equipment should be of suitable size and have:

* Outdoor exhaust space and exhaust pipe;
*filter;
* Spare fan and backup system;
* Heating and cooling rings;
* spare exhaust pipe;
* ducts, boxes, zones, and recorders;
* Air damper;
* return area;
* exhaust reserve;
* return fan;
* Controls, etc.

Return reflux can replace air exchange. Use air cleaners, auxiliary exhaust systems, and equipment monitoring systems when used. And regular maintenance and inspection.

Return criteria* Protection of personnel should be the primary consideration for design;
* The system should be able to decompose as many pollutants as possible in the most economical manner;
*The system should not be designed to meet the PEL standards only;
* The system should not significantly increase the content of harmful components;
*Reflux should not be used in the presence of cancerous substances;
* The system should have insurance devices and backup systems, especially alarm devices and carriage return devices in important areas;
* To ensure the continuity and reliability of waste recycling, cleaning and filtration equipment should be used;
* The auxiliary exhaust device should be installed to prevent the system from malfunctioning;
* The system should be equipped with feedback devices to monitor the system operation. Such as static pressure plugs, dust calculators and ampere meters;
*Reflux system should not be used when the equipment is faulty.
* Staff should be trained before using the system;

Indoor Cleaning and Static Control Dust control is a must for all screen printers. Screen printing can print on the surface of many kinds of objects, such as mirrors, films, converters, circuit boards, plastic products, and some objects that need to completely cover the ink. At this time, particles in the air will bring a lot of troubles. Therefore, higher indoor cleaning standards are required. Anti-static surfaces are especially valuable for areas that can cause static problems.

It is necessary to install training on the use of cleaning equipment. Through training, employees get the following related information: installation, equipment, furniture, supply, decoration, cleaning services and installation services.

Before deciding to install a suitable room cleaning system, you must understand the following issues:

*What is a cleaning workshop?
What are the basic types of cleaning workshops?
* What is the contaminant?
* Source of contaminants?
* Causes of contaminants?
*What are the precautions for the cleaning workshop?

The standard cleaning workshop: can be placed anywhere in the factory; many standard systems have plastic strips or curtains that do not affect the line of sight at the entrance or exit of the enclosed area; the acetic acid strips can also be applied to emergency exits and exits.