Bi-directional in-line detonation flame arrester - G 31 N | KITO Armaturen

KITO G 31 N – Bidirectional In-Line Flame Arrestor IIB3

The KITO® FS-Det4-IIB3-…-1.2 is a bidirectional in-line flame arrestor designed for gas phase piping systems. It is specified for ignition gas lines and instrument protection connections where containment of stable detonation is required from both directions in the line.

Operating Limits

• Explosion groups: IIA1 to IIB3
• MESG: ≥ 0.65 mm
• Max operating pressure: 1.2 bar abs.
• Max operating temperature: 60 °C
• Protection function: bidirectional
• Connection: internal and external thread

Connections and Dimensions

Thread sizes range from G ½" to G 2". Body height is 69 mm for G ½", G ¾", G 1"; 107 mm for G 1¼", G 1½", G 2". Size selection must be based on required flow and allowable pressure drop, not only nominal thread size.

Construction Materials

Technical datasheet specifies:

• Body: stainless steel 1.4571
• Gasket: PTFE
• KITO® grid: stainless steel 1.4571
• Intermediate layer: 1.4571

Application Selection

Compared to G 30 N, the G 31 N covers a stricter explosion group up to IIB3 (vs IIA). No certified -T / -TT version or burn time rating for stabilized burning is listed in the available datasheet. For applications with risk of continuous burning, select a type with appropriate certification and thermal monitoring.

Flow curves are provided for air at ρ = 1.29 kg/m³, 273 K, atmospheric pressure. For other gases, correct for density.

Certifications

Supplied with type certificate per EN ISO 16852 and CE marking according to ATEX 2014/34/EU.

FAQ

Does it cover IIC?
No. Approval is limited to IIB3.

Is it a check valve?
No. It is a passive flame transmission barrier, not a non-return valve.

Does it have an actuator?
No. It is not an actuated valve and no PT100 is specified in the datasheet.