ESAB CIGWELD COMET, Руководство по эксплуатации

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1.07 Flashback Arrestors
A flashback occurs when mixed gases within a cutting and welding blowpipe system ignite and, due to several possible
reasons burn back through the system against the flow of gas. The consequences of a flashback range from sooting of
the hose, to serious equipment fires and possible explosion. Low operating pressures, inadequate gas supply, damaged
equipment or poorly maintained equipment substantially increase the likelihood of flashbacks occurring. Flashback
arrestors correctly used virtually eliminate the possibility of a flashback causing harmful damage.
CIGWELD’s market leading range of COMET flashback arrestors conform to national and international standards
(AS4603, EN 730, ISO 5175 - Connection fittings to AS4267) and are manufactured under an ISO9001 accredited quality
management system. This comprehensive range includes products suitable for all applications.
CIGWELD’s COMET flashback arrestors have been designed with state of the art technology to provide the ultimate
protection and virtually eliminate flashbacks because it is impossible to either predict or completely eliminate the
potential hazard of a flashback.
Standards
Australian Standard AS 4267 - 1995 Pressure Regulators for use with Industrial Compressed Gas Cylinders recommends
flashback arrestors be used in Oxy-fuel gas applications. Australian Standard AS 4289 - 1995 Oxygen and Acetylene Gas
Reticulation Systems, specifies the use of flashback arrestors in Oxy-fuel applications. AS4603 is a new standard for
flashback arrestors only. Make sure the flashback arrestors you use now have this labelled on them.
Testing
AS 4289-1995 states flashback arrestors shall be tested annually,
this can be done by one of CIGWELD’s extensive
network of accredited service agents. Flashback arrestors should also be tested if they have been subjected to backfiring
and flashbacks. Contact your nearest distributor for advice on the correct type of flashback arrestors that should be fitted
to cater for your application(s)
NOTE: In Western Australia the Occupational Safety and Health Regulations 1996 (Reference 3.98) requires flashback
arrestors to be fitted at the outlet side of each regulator or gas discharge of a manifolded cylinder pack; and at the
blowpipe. This is also supported by Australian Standard AS 4839 that recommends the use of flashback arrestors and
list 3 options in order of preference for their fitment. CIGWELD recommends fitting flashback arrestors to both the
regulator outlet and blowpipe inlet connections, providing the ultimate protection for the operator.
1.08 Gas Welding Hose
Gas welding hose is an essential yet vulnerable link in the system that provides flexibility and freedom of movement for
the operator.
Quality hoses, such as CIGWELD’s COMET hoses, which comply to Australian Standards, are desi
gned and
manufactured to safely withstand high pressures, crushing, contact with certain chemical compounds, contaminants,
ignition as well as burning, and environmental abuse. Hoses however are the weakest point of the Oxy-fuel system and
provide potentially the greatest source of gas leaks. As a result, only quality hose which complies to AS 1335 - 1995
should be used (in conjunction with compatible hose fittings), so as to maximise the safety and durability of this part of
the system. Welding hoses which comply to Australian Standards are colour coded to the gas for which they are to be
used (Red-Acetylene, Blue-Oxygen, Orange-LPG, and Black-Inert).
Hose assemblies should be checked regularly for gas leaks, signs of external damage, perishing and for fit up to the hose
fittings. If required the necessary repairs or replacement should be made immediately. For large flow applications and
long lengths of hose 10mm or 13mm bore hose should be used.