Shenxay portlashdan himoyalangan
Portlashdan himoyalangan yoritish moslamalaridagi portlashdan himoyalangan belgilar portlashdan himoyalangan darajani tavsiflovchi yorliqdir., harorat guruhi, turi, va yoritish moslamasining qo'llaniladigan joylari.
Portlashdan himoyalangan belgilarni tushuntirish:
GB bo'yicha 3836 standartlar, yoritish moslamalarining portlashdan himoyalangan belgilarini o'z ichiga oladi:
Portlashdan himoyalangan tur + Uskunalar toifasi + (Gaz guruhi) + Temperature Group.
1. Portlashdan himoyalangan tur:
Table 1 Basic Types of Explosion-Proof
| Explosion proof form | Explosion proof form sign | Explosion proof form | Explosion proof form sign |
|---|---|---|---|
| Olovga chidamli turi | EX d | Sand filled type | EX q |
| Kengaytirilgan xavfsizlik turi | EX e | Inkapsulyatsiya | EX m |
| Barotropic type | EX p | N-turi | EX n |
| Ichki xavfsiz turi | EX ia EX i | Special type | EX s |
| Yog 'invaziyasi turi | EX o | Dust explosion-proof type | EX A EX B |
2. Uskunalar toifasi:
Electrical equipment for portlovchi gas atmospheres is divided into:
I sinf: For use in coal mines;
II sinf: For use in explosive gas atmospheres other than coal mines.
Class II explosion-proof “d” va ichki xavfsizlik “i” electrical equipment are further divided into IIA, IIB, and IIC classes.
Electrical equipment for yonuvchan chang environments is divided into:
Type A dust-tight equipment; Type B dust-tight equipment;
Type A dust-proof equipment; Type B dust-proof equipment.
3. Portlashdan himoyalangan belgilarni tushuntirish:
The ability of an explosive gas mixture to propagate an explosion indicates its level of explosion hazard. The greater the ability to propagate an explosion, the higher the danger. This ability can be represented by the maximum experimental safe gap. Qo'shimcha, the ease with which explosive gases, bug'lar, or mists can be alangalangan also indicates the level of explosion hazard, represented by the minimum igniting current ratio. Class II explosion-proof or intrinsic safety electrical equipment is further classified into IIA, IIB, and IIC based on their applicable maximum experimental safe gap or minimum igniting current ratio.
Table 2 Relationship between the Group of Explosive Gas Mixtures and the Maximum Experimental Safe Gap or Minimum Igniting Current Ratio
| Gaz guruhi | Maksimal sinov xavfsizligi bo'shlig'i MESG (m m) | Minimal ateşleme oqimi nisbati MICR |
|---|---|---|
| IIA | MESG≥0,9 | MICR＞0,8 |
| IIB | 0.9＞MESG≥0.5 | 0.8≥MICR≥0,45 |
| IIC | 0.5≥MESG | 0.45＞MICR |
4. Temperature Group:
Yonish harorat of an explosive gas mixture is the limit temperature at which it can be ignited.
Electrical equipment is classified into T1 to T6 groups based on their highest surface temperature, ensuring that the maximum surface temperature of the equipment does not exceed the permissible value of the corresponding temperature group. The relationship between temperature groups, equipment surface temperature, and the ignition temperature of yonuvchan gases or vapors is shown in Table 3.
Table 3 Relationship between Temperature Groups, Equipment Surface Temperature, and Ignition Temperature of Flammable Gases or Vapors
| Harorat darajasi IEC/EN/GB 3836 | Uskunaning eng yuqori sirt harorati T [℃] | Yonuvchan moddalarning yonish harorati [℃] |
|---|---|---|
| T1 | 450 | T＞450 |
| T2 | 300 | 450≥T＞300 |
| T3 | 200 | 300≥T＞200 |
| T4 | 135 | 200≥T＞135 |
| T5 | 100 | 135≥T＞100 |
| T6 | 85 | 100≥T＞8 |
5. Requirements for Setting Markings:
(1) Markings should be prominently placed on the main body of the electrical equipment;
(2) The markings must remain clear and durable under potential chemical corrosion. Markings such as Ex, portlashga chidamli tur, kategoriya, and temperature group can be embossed or debossed on the visible parts of the casing. The material for the marking plate should be chemically resistant, such as bronze, guruch, yoki zanglamaydigan po'latdan.