AXXIOM Manufacturing, Inc. SCHMIDT, Руководство по эксплуатации и обслуживанию

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© 2013 Axxiom Manufacturing, Inc.
5.7 Thompson Valve® II (abrasive metering valve)
The Thompson Valve (#14) is a normally closed valve that opens to supply abrasive into the
blast air stream. The Thompson Valve opens when it receives air to its signal port (see Section
9.2(a) and 9.2(b)). This happens when the deadman lever (#12) is pressed down which sends an
air signal to the Thompson Valve. When the deadman lever is released the air signal from the
blast control valve vents and Thompson Valve spring closes to stop abrasive flow to the blast
hose (#10) and nozzle (#11).
The Thompson Valve® also controls (meters) abrasive flow by use of an adjustable orifice. The
amount this orifice opens is controlled by turning the knob at the top of the Thompson Valve.
The knob sets the stopping point of the plunger (See Section 9.2(a) and 9.2(b)). Turning the
knob clockwise reduces the orifice size which decreases abrasive flow. Turning the knob
counter-clockwise increases the orifice size which will increase the abrasive flow to the blast
nozzle. The Thompson Valve II spring retainer has lines on the side to use as reference as to the
amount the orifice is open. Adjustments to the abrasive flow should be made by turning the
knob a little at a time. Test the adjustment by starting the blast for a short period to determine if
further adjustment is needed. See Section 9.2.
The Thompson Valve II has a cleanout port where a ball valve can be installed and used to
purge trash that blocks abrasive flow. This is done by opening the clean out valve and pressing
down the deadman lever (#12). The blast air flow purges trash through the clean out valve.
Airborne particles and loud noise hazards from purge air can cause serious injury and loss of
hearing. Wear approved eye and ear protection. Stay clear of purge air path. DO NOT place
hands or other body parts in the purge air path. Make sure no personnel are in purge air path.
Figure 5.3 – Mini Abrasive Blaster with pneumatic deadman controls