Air Products Gasguard 250, Руководство по установке

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Section 3: Tubing Connections
Revision C: May 1997 Page 3 - 9
3. In silane service, an air velocity of 200 feet per minute must be achieved
across all unwelded fittings per UFC Article 80, Section 8004.1.18, 1994
edition.
The table below lists the exhaust requirement for GG250 VMB Enclosures to meet
the above requirements.
Standard Enclosure Duct Size Hatch Status Exhaust Requirement
Static Pressure
Requirement
(inches water column)
4 branch (24") 6" Open
Closed
230 CFM
188 CFM
0.11"
0.19"
8 branch (30") 6" Open
Closed
335 CFM
280 CFM
0.23"
0.42"
Silane (SiH4)
Enclosure Duct Size Hatch Status Exhaust Requirement
Static Pressure
Requirement
(inches water column)
4 branch (24") 6" Open
Closed
400 CFM
375 CFM
0.33"
0.40"
8 branch (30") 6" Open
Closed
470 CFM
450 CFM
0.45"
0.50"
The static pressure is measured in the exhaust duct 3 to 6 inches above the
entrance to the round duct.
Baffles are used within the enclosure in silane service to direct the major
portion of the exhaust flow across the panel piping.
This exhaust system must be independent
of any general plant exhaust system and
must be designed for the types of gases
being used. Ensure that only compatible
gases are fed into the exhaust system. Be
certain the exhaust system power and shut
down interlocks comply with UFC and
NFPA code requirements.