Hypertherm HT400 Air Injected Water Muffler System - Manual (Page 24)

OPERATION & MAINTENANCE
Page 3-3 Air Injected Water Muffler System
Instruction Manual
This is done by lowering the torch to approximately 1/4-inch (6mm) above the top
surface of the workpiece.
Underwater Cutting
At the water table, ensure the water level is maintained at three inches or more
above the top surface of the workpiece. Due to water muffler system pressure drops,
the pressure setting of 30 psig (2.0 bar) may be insufficient to supply the 20 scfm
(566 l/m) flowrate. If this is the case, increase the pressure until the proper flowrate
has been achieved.
It is recommended that initial height sensing (IHS) be used when cutting under
water. If IHS is not used, manually position the torch as in above-water cutting.
MAINTENANCE
To maintain the Air Injected Water Muffler System, periodically inspect, clean, and
replace components as required. In the event the system does not work properly,
determine if the problem is air pressure, water pressure or if one or both of the 120
VAC control signals are missing.
Nozzle Assembly
To inspect and clean the nozzle assembly, refer to Figure 2-1 and proceed as
follows:
1. Loosen the clamping screw securing the nozzle assembly or to the torch.
2. Pull the nozzle assembly (# 034114 or # 034118) with air deflector sleeve
(# 034116) and water sleeve (# 034115) off of torch.
3. Grasp the air deflector sleeve and simultaneously twist and pull to remove. With
a cloth wipe the bottom, sides and inside of sleeve.
4. Grasp the water sleeve and simultaneously twist and pull to remove. With a cloth
wipe the sides and inside of sleeve.
5. Apply a small amount of silicone grease to the O-rings inside the nozzle assem-
bly.
6. Slide the nozzle assembly onto the torch and position the upper edge of the
nozzle assembly flush with where the torch and torch insulating sleeve meet.
Secure nozzle assembly to torch main body with clamping screw.
7. Slide the water sleeve hole end first, up into the nozzle assembly until it seats.
8. Prior to positioning the air delflector sleeve check the consumables (nozzle, swirl
ring, and electrode) and replace if necessary. Refer to the applicable instruction
manual for detailed information.
9. Slide the air deflector sleeve up inside the water sleeve until it seats.