Minnich A-1C, Руководство оператора и сервисное руководство

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TROUBLE SHOOTING AIR DRILL
PROBLEM CAUSE REMEDY
NOT ENOUGH AIR REACHING
DRILL. IT SHOULD HAVE
100SCFM PER DRILL AND 110 PSI
AT DRILL MANIFOLD WHEN
DRILLING WITH LARGE DRILLS
ON MULTI DRILL UNITS, TURN OFF ONE OR TWO
DRILLS. IF THE REMAINING DRILLS PICK UP SPEED,
CHECK THE AIR COMPRESSOR.
RESTRICTION IN AIR LINE
A FOREIGN OBJECT IN THE AIR LINE OR POSSIBLY A
REDUCTION IN THE AIR LINE CAUSED BY A REDUCER
FITTING.
TOO SMALL AIR LINE
FOLLOWING ARE SUPPLY LINE SIZES FOR DRILLING:
A-1 SINGLE DRILL 3/4"
A-2 TWO DRILLS 1-1/4"
A-3 & A-4 THREE & FOUR DRILLS 1-1/2
A-5 FIVE DRILLS 2"
AIR PRESSURE TO CYLINDER
“FEEDING” DRILL INTO
CONCRETE NOT ADJUSTED
PROPERLY
EXCESSIVE PRESSURE CAN CAUSE DRILL TO “BIND
UP” IN THE HOLE. PRESSURE THAT IS TO LOW WILL
NOT “FEED” THE DRILL INTO THE CONCRETE. THE AIR
PRESSURE REQUIRED VARIES WITH THE DRILL
MODEL.
HORIZONTAL – ALL UNITS WITH LARGE DRILLS USE
22-26 PSI. DRILL UNITS USING THE 15LB CLASS DRILL
WILL USE 16-20 PSI.
VERTICAL – ALL DRILL UNITS USE 5-6 PSI. WITH THE
CORRECT AIR PRESSURE, THE DRILL STEEL SHOULD
HAVE A SLIGHT RATTLE.
INSUFFICIENT AIR FLOW TO
KEEP HOLE BLOWN CLEAN
CHECK FOR OBSTRUCTION IN THE BLOW TUBE IN
THE DRILL.
LUBRICATOR PUTTING OUT TOO
MUCH OIL TO DRILL
IF YOU NOTICE MORE THAN A LIGHT FILM OF OIL ON
THE AIR DEFLECTOR ON THE BOTTOM OF THE DRILL,
ADJUST THE LUBRICATOR. MAKE CERTAIN YOU ARE
USING THE TYPE OF OIL CALLED FOR IN THE
OPERATION AND MAINTENANCE MANUAL.
MECHANICAL BINDING OF DRILL
CARRIER
MAKE SURE THE EIGHT BEARING PADS ARE
ADJUSTED CORRECTLY. THE SQUARE TUBE THAT
THE DRILL CARRIER SLIDES ON MUST BE FREE OF
RUST SO THAT THE CARRIER SLIDES FREELY. DRILL
STEEL MUST NOT BE BINDING IN THE GUIDE
BEARING.
BENT DRILL STEEL, WORN DRILL
BIT OR DRILLING INTO REBAR
REPLACE THE DRILL STEEL OR BIT. IF DRILLING INTO
REBAR, MOVE THE DRILL.
DRILL RUNS SLOW OR DOES
NOT DRILL EFFECTIVELY
USING 3 1/4” SHANK DRILL
STEEL IN 4 1/4” SHANK CHUCK
DRILL
THE DRILL STEEL WILL ROTATE BUT IT WILL NOT
ALLOW THE DRILL PISTON TO HAMMER PROPERLY.
REPLACE IT WITH THE CORRECT 4 1/4” DRILL STEEL.