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AC/OX CUTTING/WELDING/BRAZING

Flashback Arrestors

Flashback Arrestors Type W-66S and

S-55

Maritime authorities, such as the Norwegian Maritime Directorate, require the installation of flashback arrestors for acetylene and oxygen, as incorrect maintenance or use of gas welding equipment may cause flashbacks of various types.Normally these will stop in a well designed torch, and are only noticed as a popping sound in the torch. However, faulty handling, maintenance or gas pressure setting may lead to a penetrating flashback. This means that the gas flame passes back through the hose(s). In some cases it may also pass the regulator and ultimately reach the cylinder. The flashback arrestors supplied by Unitor are designed for use both with gas cylinders and gas outlet stations and incorporate several safety functions:

• Indicator lever showing that the pressure activated cut-off has been activated. The lever is also used for resetting the flashback arrestor. (W-66 only) • Indicator ring showing that the pressure activated cutt-off has been activated. The ring is also used for resetting the flashback arrestor (S55 only) Conform to: EN 730/ISO 5175 BAM Certification No: ZBF/009/12 Full instructions for use are supplied with the units.

Description

Capacity (m3/hour)

Capasity (l/hour)

W-66S f/Acetylene W-66S f/Oxygen S55 f/Acetylene S55 f/Oxygen

19   19 000 110 110 000 8,5    8 500 50   50 000

Type W-66S

Type S55

• Non-return valve preventing reverse flow of gases, thereby preventing a gas mixture from reaching pipelines or cylinders.

• Flame filter to quench the flame front of a flashback or a burnback. • Temperature activated cut-off to prevent further gas supply in case of fire (activated if the temperature rises to approx. 100°C). • Pressure activated cut-off to prevent further gas supply after a flashback (activated by the pressure shock in front of the flashback). • Pressure relief valve to vent off excessive pressure in case of flashback or wrongly set working

5.01

pressure (on W-66S only).

488

As a general rule: Flashback arrestors should be replaced with 5 years intervals.

At inlet

pressure (bar) Product no. 1,5 10 1,5 10

171 183970 171 302976 171 708537 171 708545