Sewon Q&TECH
제품소개
세계를 향한의지, 세원은 세계초일류 기업으로 세계를 경영해 나갑니다.
Flame Arrester
최고의 신뢰성 고품질을 추구하겠습니다.
(주)세원큐엔텍에서는 폭굉(Detonation) 역화방지기를 포함하여 산업설비 및 용기의 안전 설비로써 사용되는 많은 종류의 역화 방지기를 개발 하였습니다.
역화방지기는 기기(器機) 및 장치를 화염으로부터 안전하게 보호하는 기구이며, 인화성 가스가 저장된 탱크의 Venting 라인, 가스 덕트 라인, 배관 라인에
설치하고 있습니다.
정전기에 의한 스파크나 화염에 의하여 인화성 가스의 온도가 인화점까지 도달하여 점화되게 되고 결국 급격한 폭발이 발생될 수 있는데,
역화방지기는 화염이 전달되는 중간에서 화염을 차단하는 아주 중요한 안전 장치입니다.
역화방지기는 구조에 따라 Crimped ribbon arresters, Parallel plate arrester, Pebble arresters, Hydraulic arresters, Wire screen arresters,
Wire packed arresters and Sintered arresters등 여러 가지 종류가 있으나,
현재는 Crimped ribbon arrester type이 가장 보편적으로 사용되고 있습니다. 또한, 각각의 구조에 따라 고유한 특성과 성질이 있으므로 용도별로 구분하여
사용하여야 합니다.
(주)세원큐엔텍의 Crimped metal flame arresters는 배관 라인내에 있는 가연성 가스나 증기를 통하여 화염이 확산되는 것을 효과적으로 방지할 수 있도록
설계되어 있습니다.
즉, 화염이 특정 설비에 들어가고 나가는 것을 차단하거나 화염 확산을 억제 시킬 수 있으며, 운동하는 부품없이 화염을 자동으로 차단하는 구조로 되어 있습니다.
가연성 기체와 공기의 혼합물에 점화 되었을 때, 연소되는 기체 혼합물에서 발생하는 열을 역화방지기가 흡수, 발산시켜 반대쪽(Protected side)에 있는
가연성 기체가 자연 발화 온도에 오르지 않도록 연소 온도를 낮추어 줍니다.
이것은 가열된 높은 열을 가진 가스가 역화 방지기를 통과 하면서 열을 역화 방지기의 셀벽에 빼앗기기 때문입니다.
Critical infomation needed for. the proper application of flame and detonation arresters
Chart 1shows the effect of increases in pipe length on flame front speed and pressure. A 4.3% propane/air mixture is ignited in a 2" pipe.
20 feet of straight 2" pipe produces a flame speed of 550 feet per second.
When this piping length is increased to only 36 feet, a flame speed of 6400 feet per second is recorded. This is a clear detonation
(the movement of a flame through a gas or vapor within a medium at the speed of sound in that medium).
A standard vent-line/in-line flame arrester can be rendered ineffective.
For a 4.3% propane/air mixture, the stable detonation velocity is 5800 feet per second.
As pipe length increases, flame speeds measured at the arrester increase. For a specific and
narrows range of pipe lengths, pressures and velocities in excess of those associated with
stable detonation are encountered.
This is knows as an overdriven detonation devices in this overdriven range to verify
their effectiveness.
Any irregularities in the piping configuration (bends, changes or obstructions) tend to
increase the turbulence in the unburned vapors. Because turbulence provides the mechanism
for acceleration of the
flame font, such irregularities result in higher flame speeds.
As we see in Chart2, 6.25 feet of straight piping will yield a flame speed of 180 feet per second. Introduction of only 90 degree bend and 16 feet of
straight piping accelerates the flame front to a detonation. Not taking these bends, irregularities or obstructions into consideration can easily lead
to a misapplication of the arrester.
Chemical Classifications
In the National Electric Code (see Table 1), chemicals are grouped according to their burning and explosion characteristics. The classifications
consider the MESG-Maximum Experimental Safe Gap (see Glossary of Terms for definition), maximum explosion pressure, and minimum ignition
temperature of the specific gas or vapor.
The categories recognized are Group A, B, C, and D. Group D atmospheres represent the least volatile flammable atmospheres, and the chemical
are represented as progressively more volatile through Groups C, B and A respectively. The stable detonation velocities and quenching diameters
of some of the common chemicals identified as representing Groups A, B, C and D are shown in the following table :
Gas | Group | Quenching Diameter | Detonation Velocity |
---|---|---|---|
methane | D | 0.145 inches | 5800 FT/S |
propane | D | 0.105 inches | |
butane | D | 0.110 inches | |
hexane | D | 0.120 inches | 700 FT/S |
ethylene | C | 0.075 inches | |
hydrogen | B | 0.034 inches | |
acetylene | A | 0.005 inches |
Table 1 Chemicals by groups
Gas | Chemical |
---|---|
Group A | acetylene |
Group B | butadiene, ethylene oxide, hydrogen, manufactured, gases containing, more than 30%, hydrogen(by volume), propylene oxide |
Group C | acetaldehyde, cyclopropane, dietyl ether, ethylene, unsymmetrical, dimethyl hydrazine |
Group D |
acetone, acrylonitrile, ammonia, benzene, butane, 1-butanol(butyl alcohol), 2-butano(secondary butyl alcohol), n-butyl acetate, isobutyl acetate, ethane, ethanol(ethyl alcohol), erthyl acetate, ethylene dichloride, gasoline, heptanes, hexanes, isoprene, methane(natural gas), methanol(methyl alcohol), 3-methyl-1-butanol(isoamyl alcohol) methyl isobutyl, ketone, 2-methyl-1-propanol(isomyl alcohol), 2-methyl-2-propanol(tertiary butyl alcohol), petroleum naptha, octanes, 1-pentanol(amyl alcohol), propane, 1-pentanol(amyl alcohol), 2-pentanol(isoamyl alcohol), propylene, styrene, toluene, vinyl acetate, vinyl chloride, xylenes |
Only proper testing of flame arresters and detonation arresters can qualify their design and effectiveness within a particular chemical group.
An arrester tested with a Group D vapor is considered to be suitable for use with other Group D atmospheres and pressures are comparable.
Note, however, that an arrester tested with a Group D chemical is not necessarily suitable for use with Group C, B, or A chemicals.
Arresters tested with a higher level chemical group are generally acceptable for use with lower level groups (a Group C arrester would be suitable
for a Group D service) but should not necessarily be considered to be suitable for use with higher level groups
(a Group C arrester should not be assumed to be suitable for use in a Group B service).
How to order
MODEL | SIZE | MATERIALS | FLANGE DRILLING | OPTION |
---|---|---|---|---|
Body / Flame Element |
||||
SFC SFG SFE SFH SFO SFD SFJ SFK SFL |
A1 : 1/2" A2 : 3/4" 01 : 1" 1A : 1-1/2" 02 : 2" 2A : 2-1/2" 03 : 3" 04 : 4" 06 : 6" 08 : 8" 10 : 10" 12 : 12" SS : Special |
C : Carbon Steel 4 : 304 S.S 5 : 304L S.S 6 : 316 S.S 7 : 316L S.S A : Aluminum H : Hastelloy L : Alloy 20 S : Special Material |
AR : ASME Class 150 RF AF : ASME Class 150 FF KR : KS/JIS 10K RF KF : KS/JIS 10K FF NO : NO Drilling SS : Special |
O : No Option J : Steam Jacket T :Temperature Monitoring Sensor (Unprotected side only) B : Temperature Monitoring Sensor (Both sides) S : Special |
Example
Means a 8" model SFG with 304 stainless steel body, 316L stainless steel flame element,
ASME Class 150 RF flange drilling and no other option.