5 things you need to pay attention to regarding piping projects in explosion-proof areas!

Piping in explosion-proof areas
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Some industries are dangerous in their production operations, and may produce or use flammable gases/liquids, or may become flammable through some chemical reactions, such as: petrochemical industry, chemical factory, semiconductor technology process … ..Wait.
Therefore, these factories usually have explosion-proof areas, and equipment and materials within the explosion-proof range must have special explosion-proof measures. In all process plants, in addition to electrical installations, special attention may also need to be paid to the location of ignition sources within the plant.


Definition of explosion-proof engineering materials

According to the regulations on occupational safety and health facilities, in places where explosive dust exists and there is concern about explosion/fire, the electrical facilities, machinery, appliances or equipment used should have explosion-proof structures suitable for their installation and use.
Therefore, in the construction planning of explosion-proof areas, Longzhong will pay special attention to the selection of explosion-proof pipelines and explosion-proof control panels to ensure the safety of the engineering environment in subsequent overall use.

The performance, structure, testing, marking and hazardous area division of explosion-proof equipment should all comply with the national standard CNS 3376 (CNS15591) series, the international standard IEC 60079 (IEC61241) series or their equivalent standards. (When there is any inconsistency between the national standard series and the international series, the regulations of the international series shall prevail)

※ Explosion protection/explosion protection (explosion protection) definition:
1. Avoid creating explosive atmosphere
2. Avoid ignition sources or limit their energy
3. Limit the explosion to a damage-free range and extent


5 things you need to pay attention to regarding piping projects in explosion-proof areas!

Explosion-proof prevention box Longzhong industrial piping and wiring

1. Use blocking box
The blocking box prevents explosions in explosion-proof electrical boxes from spreading to piping. I have seen cases in which the wire entrances and exits of pressure-resistant explosion-proof devices were not equipped with blocking boxes. After an explosion occurred, the flame and pressure spread from the wire entrances to the outside.
Therefore, it is necessary to pay attention to the installation position of the blocking box as close as possible to the wire entrance and exit.

2. Seal explosion-proof powder in a barrier box
Only by filling the prevention box with explosion-proof powder can the explosion in the explosion-proof box be prevented from spreading to the piping. If you fail to use explosion-proof powder for filling correctly or use explosion-proof powder without explosion-proof certification, the prevention box will be useless.

3. Use more than 5 threads for pipeline connection and lock them firmly.
To maintain normal explosion-proof functions, the explosion-proof connection port and its connected equipment must be firmly connected, especially the bolts on pressure-resistant and explosion-proof electrical appliances. If there is no locking, the joint surface gap will not only fail to maintain the explosion-proof function, but also easily cause the pipeline to fall off or be damaged, making it easier for flammable gases and other substances to enter the pipeline. This will not only cause corrosion or damage to the pipeline, but will also affect the explosion-proof function and future maintenance work.

4.Adopt explosion-proof cable connector
When cables enter the distribution box, an explosion-proof cable gland (Cable gland) can be used to effectively block flammable gases and vapors and prevent them from spreading to other electrical equipment through gaps in the wires and causing explosions.

5. Appearance inspection of explosion-proof electrical equipment
During routine maintenance, the outer shell of the explosion-proof box needs to be checked to see if it is corroded or unstable due to time or environment. If the appearance is seriously damaged, it is recommended to replace it to avoid losing effectiveness/increasing risks.
If the case is just faded and you need to repaint it, remember not to cover the nameplate to avoid losing the recorded precautions and other information, which is very important information for inspection and maintenance.
※Source: Industrial Safety Technology Center


What are the standards for explosion-proof areas?

Regarding the division of explosion-proof hazardous areas, most of Europe uses the IEC (International Electrotechnical Commission) method, which is divided into three levels: Zone 0, 1, and 2. In the United States, Division 1 and 2 are mostly used. However, the United States has also accepted the three-level classification method in the 1996 version of NEC Standard 505, and divided Division 1 into Zone 0 and Zone 1.
Taiwan's domestic CNS 3376-10 standard refers to IEC 60079-10, which divides hazardous areas into three levels. However, Article 297 of the Indoor Wiring Installation Regulations of the Electrical Industry Act adopts the American two-level classification method.
※ Source of the above information: Occupational Safety and Health Administration of the Ministry of Labor


Longzhong has considerable practical experience in instrumentation and electrical engineering. Whether it is the assembly of control panels or the installation of equipment such as piping and wiring, we at Longzhong have very professional instrumentation and electrical engineers to provide installation support services. For more relevant performance cases, please refer to:Instrument and electrical control system

Do you have any requirements for piping and wiring in explosion-proof areas, or other instrument and electrical related issues
Longzhong provides technical consulting services | Telephone: 06-243-7822

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