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Think of the invest-ment youve madein your mechanical

pressesprobably inthe millions of dollars.

And think of howimportant it is that thepresses keep running,

day in and day out. Theypump the lifeblood through

your metalforming oper-ation, and when they

stop, so does yourincome. With that in

mind, your presses cer-tainly should be candidates

for white-glove treatment. Courtesy of

information provided by The Heim

InspectionsBring Tip-Top

Want safer and more

productive mechanical-press

operation? Then develop

a detailed press-inspection

schedule and stick to it.

BY LOUIS A. KREN, SENIOR EDITOR

Group, Chicago, IL,MetalFormingmag-azine presents guidelines for must-havepress inspections that can be performedon your shop floor by your personnel.

For greater press safety and improved

production, develop, then follow,a reg-ular press-inspection program.And beaware that press inspections are the lawof the land in metalforming.You have todo it, and you have to do it right. Set upa complete maintenance program andprocedures that include:

Press inspection Preventive maintenance Repair and replacement of com-

ponents Complete checkout after repairs.

Keep historical records,detailing all

Mechanical-Press

Performance

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maintenance, for each production press.Your press manufacturer should providespecific inspection-checklist guidelines,as different press designs and modelsrequire different inspection approach-

es. But some press-inspection tech-niques reach across all models ofmechanical presses, and these are pre-sented here.

For example, make sure that point-of-operation safety devices and acces-sory-equipment check points are part ofthe regular inspection checklist. Thesuggested frequency of inspectiondepends on operating conditions inyour plant. Ultimately, inspection fre-quency is established by the number of

shifts worked, the severity of applica-tions and production cycles.

Press inspections may be performedby various types of personnel. Dailyinspection may be assigned to operators,die setters or foremen as part of theirnormal duties. These dailies addresslubrication, loose or broken fasteners,unusual equipment noise, the func-tioning of electrical controls, faulty ormissing safety devices and any abnormaloperating conditions. More thorough

inspections should occur at predeter-mined intervalsweekly, and after thatmonthly or quarterlyand follow areference checklist.

Of course, consider safety first priorto conducting an inspection. Thatmeans a fixed slide, power off and airsupply off. The press supplier shouldhave specific information regarding safepress shutdown for inspection. Employsafety blocks and other safety equip-ment as needed. Use caution if certain

inspections require activation of somepress systems. The following checklistfor weekly and monthly inspections hasbeen provided by The Heim Group andserves as general guidance. Check withthe press manufacturer for specificsrelating to inspection of your presses.

The Weekly WalkaroundPneumatic Equipment

Inspect the air filter, shut off the airsupply and release system air pressure.

If the press is not equipped with an

automatic draining filter, release trappedmoisture and foreign matter.

Check air-gauge accuracy and con-dition and ensure proper pressuresettings.

Drain accumulated moisture fromair tanks.

If the press is equipped with coun-terbalance cylinders, drain accumulat-ed moisture from the cylinders andcheck for proper lubrication of coun-terbalances.

Check for proper operation ofvalves and solenoids that coordinateclutch and brake action. Check for airleakage from valves and then replacean entire valve if it is not working

properly.

Press-Lubrication Equipment Drain any accumulated water from

the air-lubricator bowl and fill the bowlwith proper lubricant.

Check the condition and opera-tion of the lubricator.

Check the oil level of the lubrica-tion reservoir (this should be performeddaily).

Check the lubrication system for

loose or broken tubing, worn hoses andloose fittings and connections. Makesure that the proper lubricant is usedthroughout the system, and that allpoints are receiving the proper amountof lubrication.

Address manual lubrication bychecking that all gears and pinions areproperly lubricated, and that all pointsrequiring manual greasing or oiling arebeing lubricated as required.

On presses featuring full-revolution

(mechanical) clutches, lubricate thecompression springs to prevent rusting.

Electrical Equipment Check all Run buttons for proper

guarding, and visually inspect all buttonsfor loose, cracked or broken sections.

Check the operational response ofall two-hand Run buttons, and checkStop and Top Stop buttons for properfunctioning.

Inspect all selector switches for

operational response in each designat-

ed mode, and check each selector switchfor damage and wear.

Report any unauthorized use ofselector keys to a supervisor.

Note: If theres any doubt about the

operation of buttons and switches,replace them.

General Press Equipment Check that all press covers and

guards are in place and tightly secured. Check for, and report, bypassing of

guards or safety devices. Check and report any conditions

that would require additional opera-tional guards.

Inspect the condition of personal

protective equipment and material-handling tools.

On presses with full-revolutionmechanical clutches, inspect the clutchlinkage for worn, damaged, broken orloose components, and for bent studsand screws.

Check that the single-stroke mech-anism is in place and make sure that thefoot-control cover is mounted andworking properly.

For part-revolution (air) clutch

assemblies, inspect the clutch for loose,damaged or broken parts, for air leakageand wear.

Check for proper clutch engage-ment and disengagement.

Check brakes for proper mountingand adjustment, and lining wear.

Make sure that the brake lining isfree of grease and oil.

Check that the die area is cleanand free of accumulated material, rags,chips and scrap. Use proper cleaning

procedures to prevent placement ofhands into the die area.

On a Monthly BasisFor monthly inspections, follow the

weekly checklist and add these items:

Pneumatic Equipment Ensure that adequate and correct

air pressure is being supplied to coun-terbalance cylinders, and check thatcounterbalance mounting bolts and

rods are secured tightly. Also,make sure

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that the counterbalance system doesnot leak.

Check the physical condition ofthe air-pressure switch and ensure thatit functions properly by reducing the air

pressure below the preset switch oper-ating range. Doing so must preventnormal press operation.

Check for proper operation of airgauges and the air-pressure regulator.

Ensure that the air supply is ade-quate, clean and constant.

Check the condition of all air pip-ing, tubing, hoses and fittings. Alsocheck supporting hardware for loose,broken or missing parts.

With the air pressure on, check all

air lines and connections for leaks orsmashed or broken sections.

If the press incorporates a flywheelbrake, inspect the lining for wear.

Inspect flywheel-brake mountingscrews for tightness, and actuate theflywheel brake to check operationalresponse.

If so equipped, check the conditionof the pressure-relief valve in the airtank and operate the valve manually todetermine if it is working properly.

Electrical Equipment Check that all electrical compo-

nents, wire terminals and connectionsare tightened properly, and look forpitted contacts and deposits of foreignmatter. Note signs of overheated com-ponents.

Check for properly sized motorheaters and fuses.

Check wiring for damaged insula-tion and make sure that the press frameand control panel are properly grounded.

Inspect the transformer for exces-sive heat.

Ensure proper functioning of thebrake monitor.

Inspect motor mounting bolts andmotor-bracket mounting bolts for prop-er tightness.

Clean, lubricate and service the

motor as recommended in the motormanufacturers instructions.

Check for motor overheating.Note: Replace electrical components

should there be any doubt as to their

operating condition, and ensure thatelectrical components are clean.

Fix What You FindImmediately repair, or perform

required maintenance on, any checklistitem found to be unsatisfactory, anddont use the press until thats done.Choose replacement parts that are cur-rent replacement items or approvedsubstitutes. And check results after per-forming repairs by starting the press

and performing a test run.Should repairs or extra maintenance

be required resulting from a pressinspection, dont re-enter the press intoproduction without ensuring that allguards and safety devices have beenreinstalled and are functioning properly.

MF

Press Performance

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