Check hydrostatic relief valves, Close bleed valves, Check hose discharged – Great Plains NP30A 30-foot Operator Manual User Manual
Page 72

68
NP30A or NP40A
Great Plains Manufacturing, Inc.
407-502M
2014-05-20
Check Hydrostatic Relief Valves
3.
Check that the plastic cap is in place at each valve.
In the Great Plains configuration, this would be:
Ammonia Exposure and Loss Hazards:
Understand the reason for any lifted or missing hydrostatic
relief valve caps. If a cap is out of place, that line section may
have been closed with liquid NH
3
present, which later vented,
dislodging the cap. It is also possible that the valve disc has
deteriorated and is venting at normal operating pressures.
Close Bleed Valves
4.
Put on goggles and gloves. Approach the applicator
from up-wind.
5.
Check that all bleed valves are closed:
Check Hose Discharged
6.
Visually check the general condition of the
breakaway connection
. If the two halves appear
mated, use the inlet side bleed valve
for the next
step. Otherwise treat this as a breakaway event
(page 77).
7.
Orient the bleed valve orifice so that it points away
from you and down-wind.
8.
Wearing rubber chemical gloves, slowly open the
bleed valve
by rotating the T-handle
counter-clockwise.
Check for signs that there may be residual NH
3
in
between the Acme cap and the shut-off valve:
• strong ammonia odor
• hissing of escaping gas
• valve getting cold
• dripping or spraying fluid
9.
If there are any signs of residual NH
3
, leave the
bleed valve open until the ammonia has vented, and
the inlet fittings have re-warmed to ambient
temperature. This could take tens of minutes if the
applicator was recently and improperly shut down.
10. Close the bleed valve.
•
at each cooler
•
at the outlet side of the breakaway coupler
•
at the pressure/temperature gauges.
•
at the outlet side of the breakaway coupler.
•
at the inlet side of the breakaway coupler.
Figure 54
Hydrostatic Relief Valve
31564
Figure 55
Applicator NH
3
Supply Hose
31529
Possible Chemical Hazard:
Wear your NH
3
PPE
a
. On a connection, residual NH
3
(possibly in dangerous quantities) may be present in the
applicator systems, from the inlet Acme cap to the knives or
tines. NH
3
could also be present in dangerous quantities
between the Acme cap and the cart shutoff valve. Unprotected
exposure could result in permanent lung/eye injury or death.
a. PPE: Personal Protective Equipment
A18