Shenhai-Proof Shpërthimi
Let’s start by explaining the various explosion-proof ratings, atë që nënkuptojnë, dhe si t'i zgjidhni ato në praktikë, duke përdorur si shembull kutitë e shpërndarjes kundër shpërthimit.
| Grupi i gazit/grupi i temperaturës | T1 | T2 | T3 | T4 | T5 | T6 |
|---|---|---|---|---|---|---|
| IIA | Formaldehidi, toluen, metil ester, acetilen, propan, aceton, acid akrilik, benzenit, stiren, monoksidi i karbonit, acetat etilik, acid acetik, klorobenzen, acetat metil, klorit | Metanol, etanol, etilbenzen, propanol, propileni, butanol, acetat butil, amil acetat, ciklopentani | Pentani, pentanol, heksani, etanol, heptani, oktan, cikloheksanol, terpentinë, nafta, nafte (duke përfshirë benzinën), naftë, tetraklorur pentanol | Acetaldehidi, trimetilaminë | Nitrit etilik | |
| IIB | Ester propileni, dimetil eter | Butadieni, propan epoksi, etilenit | Dimetil eter, akroleinë, karabit hidrogjeni | |||
| IIC | Hidrogjeni, gaz uji | Acetilen | Disulfidi i karbonit | Nitrat etilik |
Shenja e certifikimit:
Ex d IIB T4 Gb/Ex tD A21 IP65 T130°C është një certifikatë universale për mbrojtjen nga shpërthimi i gazit dhe pluhurit, where the part before the slash (/) indicates the gas explosion-proof level, and the part after the slash indicates dust explosion-proof.
p.sh: Explosion-proof marking, the standard format of IEC (International Electrotechnical Commission) vlerësimet e rezistencës ndaj shpërthimit.
d: I papërshkueshëm nga zjarri lloji, indicating the primary form of explosion protection is flameproof.
IIB: Represents Class B gas explosion protection.
T4: Indicates the temperatura class.
Gb: Indicates this product is suitable for Zone 1 mbrojtje nga shpërthimi.
For the shpërthim pluhuri part in the latter half, it’s sufficient to achieve the highest dust protection grade 6 based on the gas explosion-proof standards.
tD: Represents the type of enclosure protection (preventing dust ignition with enclosure).
A21: Indicates the applicable area, suitable for Zone 21, Zona 22.
IP65: Represents the protection grade.
It’s crucial to choose the correct explosion-proof rating in actual environments.
Së pari, it’s important to understand two main categories, as described below:
Explosion-proof types:
Klasa I: Electrical equipment for underground coal mines;
Klasa II: Electrical equipment for all other eksplozive gas environments except coal mines and underground.
Class II can be divided into IIA, IIB, dhe IIC, where equipment marked IIB can be used under conditions suitable for IIA devices; IIC can be used under conditions suitable for both IIA and IIB.
Klasa III: Electrical equipment for explosive dust environments other than coal mines.
IIIA: Combustible flyings; IIIB: Pluhur jopërçues; IIIC: Pluhuri përcjellës.
Explosion-proof areas:
Zona 0: Where explosive gases are always or frequently present; continuously hazardous for more than 1000 hours/year;
Zona 1: Where të ndezshme gases might occur during normal operation; intermittently hazardous for 10 te 1000 hours/year;
Zona 2: Where flammable gases are not normally present and, if they occur, are likely to be infrequent and short-lived; hazardously present for 0.1 te 10 hours/year.
It is important to note that we deal with Class II and III, Zona 1, Zona 2; Zona 21, Zona 22.
Në mënyrë tipike, reaching IIB is sufficient for gases, but for hidrogjeni, acetilen, dhe disulfidi i karbonit, a higher level of IIC is required. For dust explosion protection, just achieve the corresponding gas niveli i rezistencës ndaj shpërthimit and the highest dust grade.
There’s also a combined type of kuti shpërndarëse rezistente ndaj shpërthimit rating: ExdeIIBT4Gb.