Ametek ASR900, Руководство по установке и обслуживанию

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Maintenance | 4-27
Examining and Caring For the Flamepaths
The HAG Sample Probe Heater Assembly is designed with a flamepath
that will prevent flame propagation from within the Heater Assembly
to the outside, should an internal explosion occur. The minimum flame-
path length must be at least 9.5 mm with a maximum surface roughness
of 6.3
µm . The gap between the flange surfaces with the bolts tightened
must not exceed 0.04 mm. Use A2 stainless steel fasteners with yield stress
≥450 MPa (65,300 psi).
The flamepaths on the Heater Assembly consist of:
• The Heater Assembly joining surfaces (Heater Body and the Heater
Cover).
During each analyzer maintenance, use a feeler gauge to check the
flamepath gap between Heater (Block) Body and the Heater Cover
joining surfaces. The gap must not exceed 0.04 mm; if the gap exceeds
this value, contact AMETEK for advice.
See Warning below.
• All separable joints between the Heater Body and its Junction Box.
These parts include the threads in the Heater Body and the Junction
Box used to connect to the Thermal Insulation Tube, the threads on
each end of the Thermal Insulation Tube, the larger diameter threads
on the Junction Box and its Cover, and the o-ring groove.
See Caution
and Warning below.
If the Thermal Insulation Tube is removed, take extreme care to avoid
damaging its threads and those in the Heater Block. Also, take care to
avoid damaging the threads on the Junction Box and its cover. After
removing these parts, cover the threaded end to avoid damaging the
threads. Clean, defect-free threads are essential to ensure a flame-proof
connection.
When performing equipment maintenance in hazardous areas, all
safety standards and procedures must be followed, as specified by the
Owner Company, local electrical-inspection authority, and National/
EU regulations.
Do not apply power to the analyzer if there is damage (scratches, in-
dentations, or wear) to any flamepath. Applying power to an analyzer
with a damaged flamepath is dangerous and could result in serious
injury or death and/or serious damage to equipment. Review this sec-
tion for complete information about caring for the flamepaths.
Replace the parts immediately if damage or wear is apparent. Contact
AMETEK immediately if there is any doubt about the integrity of any
flamepath.
!
CAUTION
!
CAUTION
!
WARNING