Die Cast Machine

Safety Requirements

for the Design, Manufacture,

Maintenance and Operation

of Die Casting Machine

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TABLE OF CONTENTS

Abstract pp. iii

Personnel pp. iii

Foreword pp. iv

Explanation of Standard Format pp. iv

1. Scope, Purpose and Application pp. 1

1.1 Scope 11.2 Purpose 11.3 Application 1

1.3.1 New Installations 11.3.2 Former Installations 11.3.3 All Installations 1

1.4 Exclusions 21.5 Responsibilities 2

1.5.1 Manufacturer or Remanufacturer 21.5.2 Rebuilder or Modifier 21.5.3 System Integrator 2

2. Normative References pp. 2

3. Definitions pp. 3-11

4. Die Casting Machine Requirements pp. 11

4.1 Die Space 114.1.1 Operator’s Door 124.1.2 Additional Requirements for Powered Door 124.1.3 Rear Guard 124.1.4 Top Guard 134.1.5 Ratchet Bar 134.1.6 Hardwired Electrical Interlock(s) 144.1.7 Clamp Hydraulic or Pneumatic Interlock 144.1.8 Timed Opening 154.1.9 Area Between the Rear Guard and the Die Space 154.1.10 Cycle Initiation Control Location 15

4.1.10.1 Clear View of the Die Space 154.1.10.2 Obstructed View of the Die Space 15

4.2 Other Pinch Points 164.3 Powered Tie Bar Pulling Systems 164.4 Shot End 16

4.4.1 Cold Chamber 164.4.2 Hot Chamber 174.4.3 Vertical Shot Cylinder 174.4.4 Injection Interlock 18

4.5 Electrical Controls 184.5.1 Two-Hand Control Device 18

4.5.1.1 Unintentional Operation 184.5.1.2 Concurrent Control 194.5.1.3 Control Location 19

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4.5.1.4 Concurrent Pressure 194.5.1.5 Control Release 194.5.1.6 Next Cycle Initiation 19

4.5.2 Control Interlock Circuit 194.5.2.1 Fail-Safe Control 194.5.2.2 Operator Intervention 194.5.2.3 Machine Suspension 194.5.2.4 Additional Actions 19

4.5.3 Emergency Stops 204.5.3.1 Unobstructed Emergency Stop Device 204.5.3.2 Emergency Stop Button Design 204.5.3.3 Emergency Stop Button Restrictions 204.5.3.4 Start-Up Procedure 20

4.5.4 Power Source 204.5.5 Power Loss 204.5.6 Electrical Requirements 21

4.6 Hydraulic Fluids and Compressed Gases 214.6.1 Nitrogen 214.6.2 Air 214.6.3 Hose and Tubing 214.6.4 Accumulators 214.6.5 Hydraulic Fluids 21

4.7 Manual Mode 224.8 Safety Signs 22

5. Die Requirements pp. 22

5.1 Design, Construction, and Use 225.1.1 Size 225.1.2 Broken Parts 225.1.3 Weight 225.1.4 Mounting 225.1.5 Handling 22

5.2 Die Setting 235.3 Flash or Die Spitting 235.4 Die Changing System 23

6. System Requirements pp. 24

6.1 Ancillary Equipment 246.1.1 Metal Delivery System 246.1.2 Plunger Lubrication System 246.1.3 Die Lubrication System 256.1.4 Casting Extraction System 25

6.2 Emergency Stop Circuitry 256.3 Control Interlocks 26

6.3.1 Timers 266.3.2 Interlock Resets 26

7. User Requirements pp. 26

7.1 Training 267.2 Lockout/Tagout 267.3 Risk Assessment 267.4 Work Area 267.5 Personal Protective Equipment 26

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7.6 Ventilation 27

8. Maintenance Requirements pp. 27

8.1 Training 278.2 Lockout/Tagout 278.3 Maintenance Operations While Under Power 278.4 Stuck Plunger - Cold Chamber Machine 278.5 Stuck Casting 27

9. General Information pp. 28

9.1 Equipment Identification 289.2 Machine Manual 28

Annexes

A. Cold Chamber Die Casting Machine, Top & Side View 30B. Hot Chamber Die Casting Machine, Top & Side View31C. Vertical Die Casting Machine, Side View 32D. Die Area & Die Space, Top & Side View 33E. Typical Die Casting System 34

ABSTRACT

This safety standard governing die casting machines was prepared by a committee made up ofindustry representatives from the following areas: suppliers, users, and general interest, under thedirection of the North American Die Casting Association Board of Governors.

This safety standard governing die casting machines was approved by the American NationalStandards Institute (ANSI) on April 25, 2000 and updated for electornic distribution on November 30, 2000. In the following document, explanatory information is identified with the prefix E.

PERSONNEL - NADCA SAFETY COMMITTEE

V. L. Mangold, Jr., Chairman, KOHOL, Incorporated G. Loots, Chicago White Metal Casting

J. Rexford, Vice Chairman, HPM Corp. J. O’Brien, O’Brien Mfg. Consulting

H. Bakemeyer, DCD Consulting D. Robb, NADCA Secretariat

D. Celek, Rimrock Corporation J. Prei, Briggs & Stratton Corp.

W. Damian, Prince Machine Corp. M. Savard, Husky Injection Molding Systems

S. DeBartolo, EPCO D. Teeples, GMTI Lester PDC Inc.

T. Dyer, Southern Die Casters, Inc. J. Thornburg, Diversified Diemakers Inc.

B. Eggleston, Drion Safety Services Inc. P. Vertin, GMPT Bedford Plant

A. Eichhof, Prima Die Casting Inc. R. Wagner, Premier Tool & Die Casting Corp.

B. Garner, UBE Machinery Inc. J. Wilkey, Leggett & Platt Aluminum Group

J. Hoenle, Parker Hannifin Corp.

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FOREWORD

This Foreword is not a part of the following standard, ANSI/NADCA B152.1-2000, SafetyRequirements for the Design, Manufacture, Maintenance and Operation of Die Casting Machines, butis included for information.

The NADCA Safety Committee was organized in 1996 to provide a centralized source for theexchange of technical information between manufacturers and users of die casting machines.

The following standard, ANSI/NADCA B152.1-2000, Safety Requirements for the Design,Manufacture, Maintenance and Operation of Die Casting Machines, provides recommendations for thesafe use of die casting machines and the ancillary equipment that is routinely used in conjunction withdie casting machines.

Emphasis is placed on conformance of this process with prevailing industry standards for hazardanalysis and proper safeguarding of foundry equipment.

Comments and suggestions for the improvement of this standard are welcome. They should be sentto the Secretary of the NADCA Safety Committee, North American Die Casting Association, 9701West Higgins Road, Suite 880, Rosemont, Illinois 60018-4721.

Official interpretations of any of the technical requirements of this standard may be obtained bysending a request, in writing, to the Secretary of the NADCA Safety Committee. A formal reply will beissued after it has been reviewed by the appropriate personnel following established procedures.

Explanation of Standard Format

This standard uses a two-column format to provide both specific requirements and supportinginformation.

The left column, designated "Standard Requirements," is confined solely to these requirements and isprinted in bold type.

The right column, designated "Explanatory Information," contains only information that is intended toclarify the standard. This column is not a part of the standard.

The "Annex Information," designated Annex A through E contains only information that is intended toclarify the Standard. This information is not part of the standard.

Operating rules (safe practices) are not included in either column unless they are of such a nature asto be vital safety requirements, equal in weight to other requirements, or guides to assist in compliancewith the standard.

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CLAUSE 1: SCOPE, PURPOSE, AND APPLICATION

1.1 ScopeThe requirements of this standard apply tomachines that inject molten metal underpressure into a reusable die. This type ofmachine is commonly referred to as a diecasting machine. The scope of this standardincludes metal delivery systems, plungerlubrication systems, die lubrication systems,and casting extraction systems.

Mechanically powered die casting machines,permanent mold machines, low pressurecasting machines, and green sand castingmachines are not covered by this standard.

1.2 PurposeThe purpose of this standard is to establishsafety requirements with respect to thedesign, manufacture, maintenance, andoperation of die casting machines and use ofancillary equipment.

1.3 Application

1.3.1 New InstallationsThe requirements of this standard pertainingto design and manufacture shall apply to allnew, rebuilt, or remanufactured die castingmachines, dies, and ancillary equipmentmanufactured for installation or installed inthe United States after the compliance datesubsequent to the approval of this standard.Compliance to the standard shall be 12months after the approval date.

1.3.2 Former InstallationsWithin 48 months after the approval date ofthis standard, all die casting machines, diesand ancillary equipment, as described in thisstandard, shall be modified by the employerto the extent required to bring them intoconformity with the requirements of thisstandard.

1.3.3 All InstallationsThe requirements of Clauses 7 and 8 of thisstandard pertaining to the use andmaintenance of die casting machines shallapply to all users subsequent to the approvalof this standard.

E1.2 PurposeThe intention of this standard is to minimizehazards involved in maintaining, operating,and die setting while working on or adjacentto a die casting machine.

E1.3.2 Former InstallationsThe useful life of a die casting machine, dies,and ancillary equipment that is specified in thisstandard may extend over several decades.Existing machines that are sub-standard bycurrent safety standards should be modified inaccordance with the requirements of thisstandard.

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1.4 ExclusionsThis standard applies to die castingmachines and die casting systems only andis not intended to apply to the followingmachines:1. mechanically powered2. permanent molding3. low pressure casting4. green sand castingThis list is not intended to be all-inclusive.

1.5 ResponsibilitiesThe responsibility for the application of thisstandard is defined by this standard.

1.5.1 Manufacturer or RemanufacturerIt shall be the responsibility of the die castingmachine manufacturer or remanufacturer todesign and construct die casting machinesin accordance with Clause 4 of this standard.

1.5.2 Rebuilder or ModifierIt shall be the responsibility of any personrebuilding or modifying die casting machinesto do so in accordance with portions ofClause 4 of this standard applicable tocomponents being rebuilt or modified.

1.5.3 System IntegratorThe system integrator shall ensure that thesystem complies with Clause 6 of thisstandard. The System Integrator has theresponsibility to ensure that anymodifications made to the die castingmachine shall conform to Clause 4. Theemployer shall be the system integratorunless another party contractually acceptsresponsibility as the system integrator.

CLAUSE 2: NORMATIVE REFERENCES

2.0 Normative ReferenceThe following standards contain provisions,which, through reference in this text,constitute provisions of this AmericanNational Standard. At the time of publication,the editions indicated were valid. Allstandards are subject to revision, and partiesare encouraged to investigate

E1.5.3 System IntegratorWhen a guard is removed or modified toaccommodate a casting extraction system,alternate interlocked perimeter guardingshould be incorporated.

E2.0 Normative References1. ANSI/ASME B15.1-1992, “Safety

Standard for Mechanical PowerTransmission Apparatus.”

2. ANSI C2, “National Electrical SafetyCode.”

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the possibility of applying the most recenteditions of the standards indicated below.1. NFPA 79-1997, “Electrical Standard for

Industrial Machinery.”2. ANSI/NFPA T2.13.8-1997, “Hydraulic Fluid

Power - Fire Resistant Fluids -Definitions, Classifications, and Testing.”

3. ANSI Z535.1-1998, “Safety Color Code.”4. ANSI Z535.2-1998, “Environmental and

Facility Safety Signs.”5. ANSI Z535.3-1998, “Criteria for Safety

Symbols.”6. ANSI Z535.4-1998, “Product Safety Signs

and Labels.”7. ANSI Z535.5-1998, “Accident Prevention

Tags.”

CLAUSE 3: DEFINITIONS

3.1 AlarmAlarm means an indication that a failure ormisadjustment of a device has occurred.

3.2 Anti-repeatAnti-repeat means the part of the machinecontrol system designed to limit the diecasting machine to a single cycle if the cycleactuating means are held operated or tieddown. Anti-repeat requires release of allcycle actuating mechanisms before anothercycle can be initiated.

3.3 Anti-tie DownAnti-tie Down means a circuit designed toprevent machine operation in case a controlis permanently actuated.

3.4 Automatic ModeAutomatic Mode means a selectable mode ofoperation of the die casting machine, whichallows it to perform more than one cyclewithout cycle actuation by an operator.

3.5 BiscuitBiscuit means the cylindrical plug of metalformed by the excess metal in the coldchamber machine after a shot has beenmade.

E3.2 Anti-repeatThere shall be no inference that the purposeof Anti-repeat is to prevent an inadvertentclosing of the machine. An inadvertentclosing is the result of a malfunction.

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3.6 Casting1. n. Casting means the product that results

from the solidification of molten metal ina mold or die.

2. v. Casting means the process by whichmolten metal is poured or injected into ametal mold or die.

3.7 Casting Extraction SystemCasting Extraction System means the deviceor devices used to remove a casting from thedie area.

3.8 Cold ChamberCold Chamber means the shot system bywhich molten metal is delivered to the moldor die; this mechanism is also separatedfrom the reservoir of molten metal.

3.9 Cold Chamber MachineCold Chamber Machine means a die castingmachine in which the injection mechanism isseparated from the reservoir of molten metal.

3.10 ConcurrentConcurrent means acting in conjunction andis used to describe a situation wherein twoor more controls exist in an operatedcondition at the same time.

3.11 DeviceDevice means an invention or contrivancedesigned to perform a particular objective.

3.12 DieDie means the tooling used in a die castingmachine for imparting the shape to thecasting.

3.13 Die AreaDie Area means the space and the areaadjacent to the die that presents hazard(s)during operation.

3.14 Die Lubrication SystemDie Lubrication System means the deviceused to apply die release material to thecasting die.

E3.14 Die Lubrication SystemDie Lubrication System includes spraywands, fixed mounted sprayers, andmechanized spray devices.

E3.13 Die AreaSee Annex D.

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3.15 Die Casting MachineDie Casting Machine means a machine thatinjects molten metal under pressure into areusable die.

3.16 Die SpaceDie Space is defined as the working area ofthe die casting die between the stationaryand moving machine platens.

3.17 DoorDoor means a movable barrier that whenclosed prevents the entry of any portion of aperson’s body into the die space.

3.18 EjectorEjector means a mechanism for forcingcastings from the die cavity.

3.19 Emergency StopEmergency Stop means operation of a circuitthat overrides all machine control, removesdrive power, and causes all moving parts tostop.

3.20 EmployerEmployer means any person who contracts,hires, or is responsible for the personnelassociated with the operation, maintenance,and setup of die casting machinery.

3.21 Fixed GuardFixed Guard means a guard that cannot bemoved except with the use of tools.

3.22 Former InstallationFormer Installation means a currentlyexisting die casting machine installed priorto the compliance date of this standard.

3.23 GateGate means a movable barrier that whenclosed prevents the exposure of any portionof a person’s body to a hazard.

3.24 GooseneckGooseneck means that part of the metaldelivery system for a hot chamber machinecontaining the sleeve and metal flow pathimmersed in the metal bath.

E3.16 Die SpaceSee Annex D.

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3.25 GuardGuard means a physical barrier, whichprotects personnel from exposure to ahazardous area.

3.26 HardwiredHardwired means the components of anelectrical circuit that are permanentlyelectrically wired together, and the electricalcircuit is independent of electronic logic(hardware or software).

3.27 Hot Chamber MachineHot Chamber Machine means a die castingmachine in which the injection mechanism isimmersed in the reservoir of molten metal.

3.28 InjectionInjection means the process of forcingmolten metal into the die.

3.29 InterlockInterlock means an arrangement whereby thestatus of one control or mechanism allows orprevents the operation of another.

3.30 Interlock SwitchesInterlock Switches are an electrical ormechanical means by which operation of acomponent is prevented or maintainedunless required conditions are met.

3.31 Locked1. Locked means the secured state of a

device used to secure a switch, door, orgate.

2. Locked means the clamping mechanismof the die casting machine is in the readyto cast position.

3.32 Maintenance PersonnelMaintenance Personnel means an individualwho has been trained and authorized by theemployer to inspect, repair, and maintain diecasting machines and ancillary equipment.

3.33 Manual1. Manual means a mode of operation that

requires a deliberate and continuous actto initiate and sustain an individualfunction of the die casting machine.

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2. Manual means a text document for use asa guide or reference.

3.34 Manual ModeManual Mode means a machine operationalcontrol method that requires a deliberate andcontinuous act to initiate and sustainmovement of any portion of the die castingmachine.

3.35 ManufacturerManufacturer means any person whomanufactures a die casting machine,ancillary equipment or both for installation inthe United States.

3.36 Metal Delivery SystemMetal Delivery System means a device usedto transfer metal from the holding furnace tothe cold chamber.

3.37 ModifierModifier means any person who converts,changes or otherwise alters a die castingmachine.

3.38 Monitoring DeviceMonitoring Device means a device, whichmay be used to verify the function of anotherdevice.

3.39 Movable GuardMovable Guard means a guard, which may bemoved or removed without the use of tools.

3.40 New InstallationNew Installation means a new, rebuilt, orremanufactured die casting machineinstallation.

3.41 One-hand Control, RemotelyLocated

One-hand control, remotely located means aone-hand actuator that requires maintainedpressure from one-hand of the operator tosustain or initiate hazardous motion. Theactuator shall be located far enough awayfrom the hazardous area so that thehazardous motion has stopped before thearea can be accessed by personnel.

E3.34 Manual ModeManual Mode is commonly referred to as inchor jog.

E3.35 ManufacturerA Manufacturer may also be a modifier orrebuilder.

E3.40 New InstallationNew Installations include equipment rebuilt orremanufactured on site by the user.

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3.42 OperatorOperator means an individual who has beentrained and authorized by the employer toperform production work with the die castingmachine.

3.43 Operator DoorOperator Door means a moveable barrier thatwhen closed prevents the entry of anyportion of a person’s body into theoperator’s side of the die space.

3.44 Parting LineParting Line means the surface formed bythe separation of the die halves and/ormovable sections.

3.45 Perimeter GuardingPerimeter Guarding means guarding placedaround a die casting machine or machinecell.

3.46 Physical BarrierPhysical Barrier means a rigid boundary tosafeguard personnel access.

3.47 Pinch PointPinch Point means any point where it ispossible to be caught between moving partsor between a moving and stationary part.

3.48 PlatenPlaten means the moving or stationarymembers of a die casting machine to whichthe die is fastened.

3.49 PlungerPlunger means the piston which forces metalfrom the shot sleeve into the die and appliespressure during solidification.

3.50 Plunger Lubrication SystemPlunger Lubrication System means a systemby which a plunger lubricant is introduced tothe shot system of the die casting machinethrough either automatic or manual means.

E3.46 Physical BarrierCages, gates, walls, shields, and fences areall examples of Physical Barriers.

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3.51 Point of OperationPoint of Operation means the area of the diecasting machine, which is between the diefaces.

3.52 Pour HolePour Hole means the hole in the shot sleeveinto which the metal is poured.

3.53 Presence Sensing DevicePresence Sensing Device means a devicecapable of detecting an intrusion into aspecified area.

3.54 Ratchet BarRatchet Bar means a notched bar or rackused to prevent inadvertent die castingmachine closure.

3.55 Rear GuardRear Guard means a guard placed to prevententry into the die space at the side of themachine opposite the operator’s controlpanel.

3.56 Rear SideRear Side means the side of the die castingmachine opposite the operator’s controlpanel.

3.57 RebuilderRebuilder means any person who rebuilds allor a portion of a die casting machine forinstallation in the United States. Therebuilding may consist of any restoration ofthe machine to its original specification andcapability.

3.58 RemanufacturerRemanufacturer means any person whoremanufactures a die casting machine forinstallation in the United States. Theremanufacturer is not limited to the originalequipment specification or capability.

3.59 RestraintRestraint means a mechanism, whichprevents the die casting machine frominadvertent movement.

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3.60 SafeguardingSafeguarding means a device or procedureused to protect personnel from hazard(s).

3.61 Semi-Automatic ModeSemi-Automatic Mode means a die castingmachine operational control sequence,which allows it to perform one completecycle and then stop.

3.62 ShallShall means a mandatory requirement.

3.63 ShieldShield means a barrier that protects againstthe hazards of spitting or splashing metal.

3.64 ShouldShould means a recommended safe practice,but does not mean a mandatory requirement.

3.65 ShotShot means the injection of metal into the diecasting die. The shot end portion of themachine causes the injection of metal tooccur.

3.66 Shot SleeveShot Sleeve means the portion of the shotsystem, which guides the plunger andcontains the molten metal prior to beinginjected into the mold or die.

3.67 SignageSignage means graphic communicationwhose functions include direction,identification, information, regulation,warning, or restriction.

3.68 Suspended StateSuspended State means an operation that isstopped.

3.69 System IntegratorSystem Integrator means the party that isresponsible for assuring the system designand control interlocking of the die castingmachine and other ancillary equipment into asystem that conforms with the requirementsof this standard.

E3.63 ShieldA Shield may be a moving barrier as whenmounted on the die or a stationary barrier aswhen mounted on the floor.

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3.70 Timed OpeningTimed Opening means the initiation of theopening of the die casting machine iscontrolled by an independent timer duringthe automatic or semi-automatic machinecycle mode.

3.71 ToggleToggle means the series of connected armsand pivots mounted between the adjustableand moving platens, which when actuated,causes the platens to open or close.

3.72 Top GuardTop Guard means a guard placed to prevententry into the die space at the top of themachine.

3.73 Two-Hand ControlTwo-Hand Controls means a two-handactuator that requires simultaneous orconcurrent pressure from both hands of theoperator to sustain or initiate the motion.

3.74 UserUser means the owner or operator of a diecasting facility.

3.75 Work LevelWork Level means the surface from whichthe die casting machine and ancillaryequipment are operated.

CLAUSE 4: DIE CASTING MACHINEREQUIREMENTS

4.1 Die SpaceThe die space on the operator’s side of thedie casting machine shall have a physicalbarrier to safeguard the operator from thefollowing:1. Burn hazard associated with die spitting, bursting biscuits, and hot surfaces.2. Impact and pinch point hazards

associated with motion within the diespace area.

E3.70 Timed OpeningThe Timed Opening time may be either ahardwire or software timer. This timer isoften referred to as the “dwell” timer.

E3.73 Two-Hand ControlThe initiation of motion by a Two-HandControl may be permissible when additionalsafety devices are in place such as guards,electronic light curtains, or other deviceswhich would stop the motion of the machinewhen the safety guarding and operation hasbeen compromised.

E4.1 Die SpaceSee Clause 5 for alternate methods forsafeguarding burn hazards and Clause 6 foralternate methods for safeguarding ancillaryequipment. For further requirementspertaining to ancillary equipment see Clause6.

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4.1.1 Operator’s DoorAn operator’s door shall be provided toguard the die space.

Where a die casting machine, equipped withancillary equipment, is operated in automaticmode and an operator is not present,interlocked perimeter guarding, see clause6.1, and other safeguarding, see clauses 5.3and E5.3, may be used in place of anoperator's door.

The operator’s door shall be closed andlocked before the die casting machine closecycle can be initiated. The operator’s doorshall remain closed and locked until the burnhazard associated with a bursting biscuit ordie spitting no longer exits.

Locking of the operator’s door shall beachieved using an electrical interlock and ahydraulic, pneumatic, or mechanical device.

Closure of the operator’s door shall notdirectly initiate die closing.

4.1.2 Additional Requirements forPowered Door

Hazards created by the motions of the doorshall be safeguarded with a presencesensing device or other means to eliminatethe hazards.

The presence sensing device shall bedesigned into the circuit such that a failure ofthe device duplicates the actuation of thedevice. The power assist mechanism shallnot lessen the effectiveness of the operator’sdoor.

4.1.3 Rear GuardThe die space opposite the operator’s side ofthe die casting machine shall have a rearguard with two interlocks. The interlocksshall separately interrupt the control circuitand the power circuit to prevent all machinemovements if the guard is opened orremoved.

When a die casting machine, equipped withancillary equipment on the rear side, is

E 4.1.1 Operator’s DoorAn operator’s door should be locked duringthe following sequences:1. Once the operator’s door is closed in

“Semi-Automatic” or “Automatic” Mode.2. During clamp closing.3. During metal injection cycle, including die

close time.4. Until all pressure from injection forward

has been removed from the biscuit.

An operator's door is locked when theoperator is prevented from opening theoperator's door.

E4.1.3 Rear GuardA rear guard is designed to open and closeduring setup and maintenance functions only.

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operated in automatic mode and an operatoris not present, interlocked perimeterguarding, see clause 6.1, and othersafeguarding, see clauses 5.3 and E5.3, maybe used in place of a rear guard.

During maintenance and/or setup operations,when the rear guard or perimeter guarding isopened or removed and motion is needed,this motion shall be controlled by two-handcontrol or by a one-hand control, remotelylocated on the rear side of the machine. Theone-hand control, remotely located, shall belocated within a clear view of the die area.For any motion to occur, the operator’s two-hand control and the two- hand control orone-hand control, remotely located, on therear side must be activated simultaneouslyand remain depressed during any motion.

4.1.4 Top GuardA top guard shall be installed when it ispossible for a person standing on the floor orwork level to reach over the top of theoperator’s door or rear guard and into ahazardous area or where a spit hazard exists.When the top guard is movable, it shall beinterlocked.

During die setting, the top guard may beopen only when the die casting machine isoperated in the manual mode, see Clause 4.7.

4.1.5 Ratchet BarAll die casting machines shall be equippedwith a ratchet bar or equivalent device toprevent inadvertent platen closure wheneverthe operator’s door is not fully closed andwhenever power to the machine is lost.

A monitoring device shall be provided toverify the proper operation of the ratchet baror equivalent device. If improper operation isdetected, the die casting machine cycle shallbe inhibited and an alarm shall be activated.

Limited platen closing motion is permittedwith ratchet bar or equivalent device notengaged only during manual operation; seeClause 4.7.

4.1.6 Hardwired Electrical Interlock(s)Independent hardwired electrical interlock(s)shall be provided to prevent the following

E4.1.4 Top GuardThe intent of this Clause is to requiresafeguarding of the parting line which canspit metal to areas accessible to personnel.A low profile machine would requiresafeguarding at both sides and across thetop; a larger machine would requiresafeguarding at both sides.

E4.1.5 Ratchet BarSome platen motion may occur before theratchet bar or equivalent device is fullyengaged. The ratchet bar or equivalentdevice is not intended to resist the lock-upforce.

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motions when the operator’s door is not fullyclosed:1. die closing2. core setting3. injection forward4. ejector reset

The interlock(s) shall be so located orprotected to prevent accidental actuation.

The exception to hardwired electricalinterlock(s) shall be as follows:

Core setting, and ejector reset motions areallowed when the operator’s door is open,only when one or more of the followingconditions exist:

Condition 1: The hazardous motion iscontrolled by a two-hand control thatcomplies with Clause 4.5.1.

Condition 2: The hazardous motion isactivated by a remote switch that is locatedfar enough away from the hazardous area sothat the motion has stopped before the areacan be accessed by personnel.

The hardwired electrical interlock(s) may bebypassed in the manual mode (see Clause4.7) to provide limited platen closing motionfor the setting of dies.

4.1.7 Clamp Hydraulic or PneumaticInterlock

If hydraulic or pneumatic power is used tocause platen motion, then a hydraulic orpneumatic interlock shall be provided suchthat the platen close circuit is interruptedunless the operator’s door is closed.

The clamp hydraulic or pneumatic interlockmay be bypassed in the manual mode (seeClause 4.7) to provide limited platen closingmotion for the setting of dies.

This hydraulic or pneumatic interlock shallbe actuated by mechanical or electrical

E 4.1.7 Clamp Hydraulic or PneumaticInterlock

The hydraulic or pneumatic valve which, interruptsthe flow to the cylinder for platen closing motionshould be one of the following:1. Positively and directly actuated by the operator’s

door.2. Controlled by an independent hardwired limit

switch which is positively and directly actuatedby the operator’s door.

3. Controlled by a pilot valve, which is positivelyand directly actuated by the operator’s door.

4. Controlled by a pilot valve, which is controlledby an independent hardwired limit switch, whichis positively and directly actuated by theoperator’s door.

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means, which are independent of all otherinterlocks.

A monitoring device shall be provided toverify the operation of this hydraulic orpneumatic interlock. If improper operation isdetected, the die casting machine cycle shallbe inhibited and an alarm shall be activated.

When a die casting machine is powered bysources other than hydraulics or pneumatics,an additional independent interlock shall beprovided.

4.1.8 Timed OpeningThe minimum opening time of a die after theinjection of metal has been initiated shall bea function of an independent timer for thatpurpose. Die opening shall be inhibited untilthis timer has timed out.

4.1.9 Area Between the Rear Guardand the Die Space

Where it is possible to stand between therear guard and the die space and a hazardexists, an emergency stop pushbutton shallbe provided in a location that is readilyaccessible from this area.

4.1.10 Cycle Initiation ControlLocation

4.1.10.1 Clear View of the Die SpaceIf the position from which the operatorinitiates the machine cycle allows a clearview of the die space, a two-hand controldevice or a one-hand control, remotelylocated shall be used to initiate the machinecycle.

4.1.10.2 Obstructed View of the Die Space

If the position from which the operatorinitiates the machine cycle does not allow aclear view of the die space, one of thefollowing devices shall be provided:1. Acknowledgment system: An

acknowledgment system shall consist ofa pushbutton located in a position,which provides full view of the diespace. To start a cycle, the following

E4.1.8 Timed OpeningTimed opening is often referred to as "dwell"time.

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sequence shall be completed within a timeinterval prescribed by the die castingmachine manufacturer:

a. Acknowledgment pushbuttonactivation.

b. Close operator’s door.c. Two-hand control device or one-hand

control, remotely located, deviceactuation.

A monitoring circuit shall be provided tocheck the operation of each pushbutton.If improper operation or sequencing isdetected, the die casting machine cycleshall be inhibited and an alarm shall beactivated.

2. Presence sensing device: A presencesensing device which, when activated,shall prevent, stop, or reverse the closureof the operator’s door, and in turn, themovement of the die.

4.2 Other Pinch PointsHazards associated with other pinch pointlocations that are not otherwise identifiedshall be safeguarded. If a movable guard isused, it shall be interlocked.

4.3 Powered Tie Bar PullingSystems

Where present, powered tie bar pullingsystems shall be designed to address thefollowing hazards:1. Pinch point hazards created between the

tie bar and platens.2. Burn hazard associated with the spitting

due to unbalanced locking force on thedie.

The tie bar shall be in a properly securedposition prior to commencement ofoperation. The system shall be mechanicallyinterlocked to ensure that the tie bar issecure.

4.4 Shot End

4.4.1 Cold ChamberThe shot end of the die casting machine shallbe safeguarded to prevent personnelexposure to the following hazards:

E4.2 Other Pinch PointsOther pinch point locations include, but arenot limited to, the toggle area, die heightadjust systems, etc.

E4.4.1 Cold ChamberSee Clause 6.1 for Ancillary Equipment.

Burn hazard safeguards can include, but arenot limited to, the following:1. Physical guarding.2. Perimeter guarding.3. Personal Protective Equipment.

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1. Impact hazards caused by the movementof the shot rod and associated equipmentshall be guarded with an appropriatephysical barrier as follows:a. Hazards associated with a shot end

equipped with a metal deliverysystem shall be safeguarded withphysical barriers or perimeterguarding to prevent operators fromaccessing the plunger, tail rod, pistonrod, and metal delivery system.

b. Hazards associated with a shot endthat uses manual ladling shall besafeguarded with physical barriers orperimeter guarding to preventoperators from accessing the tail rodand piston rod. Access to the shotend from the side opposite theoperator shall be safeguarded with aphysical barrier. Additionally, hazardsassociated with the cold chamberand molten metal shall besafeguarded with appropriateoperator training, equipment, andpersonal protective equipment.

2. Burn hazards resulting from metal splashfrom the pour hole during the start of theinjection while the plunger passes thepour hole shall be safeguarded.

4.4.2 Hot ChamberThe shot end of the die casting machine shallbe safeguarded to prevent personnel fromexposure to the following hazards:1. Burn hazard from molten metal

associated with blow-out due to nozzlealignment, nozzle rupture, or breakaway.

2. Pinch point hazards between the nozzleand the platen.

3. Burn hazards due to plunger drift shall besafeguarded through the use of aninterlocked and monitored mechanicaldevice, which inhibits unintended plungermovement.

4.4.3 Vertical Shot CylinderA die casting machine equipped with avertical shot cylinder shall be safeguarded toprevent personnel exposure to the followinghazards:

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1. Impact and pinch point hazards causedby the movement of the shot cylinderpiston and attached equipment shall besafeguarded with appropriate guards.

2. Burn hazards from molten metal in thearea below the shot cylinder caused byspilling or metal splash shall besafeguarded with a physical barrier.

3. Impact and pinch point hazardsassociated with releasing stored potentialenergy in the mechanism or system usedto move the shot cylinder assembly witheach machine cycle shall be safeguardedusing one of the following methods:

a. A system that automaticallyreleases all stored potential energyin a safe manner.

b. A locking mechanism that preventsthe shot cylinder assembly frommotion.

4. Burn hazards due to plunger drift shall besafeguarded using an interlocked andmonitored mechanical device, whichinhibits unintended plunger movement.

4.4.4 Injection InterlockThe injection stroke of a die casting machineshall be interlocked to prevent the injectionof metal unless the machine is locked.

4.5 Electrical Controls

4.5.1 Two-Hand Control Device

4.5.1.1 Unintentional OperationEach hand control shall be protected againstunintentional operation.

E4.5.1 Two-Hand Control DeviceA die casting machine should be equipped with atwo-hand control device that initiates the closingand locking of the dies.Two examples of this process are provided asfollows:

1. A two-hand control device has pressuremaintained until the dies are closed.

2. A two-hand control device has pressuremaintained until the powered operator door isclosed and interlocked during manual or semi-automatic mode.

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4.5.1.2 Concurrent ControlEach hand control shall be arranged bydesign, construction, and/or separation torequire the use of both hands to actuate thecontrols concurrently.

4.5.1.3 Control Location The hand controls shall be located to preventexposure to the hazard.

4.5.1.4 Concurrent PressureEach hand control shall require continuousand concurrent pressure while the hazardexists.

4.5.1.5 Control ReleaseThe hazardous machine motion shall stop orreverse, if reverse motion does not create ahazard, when either control is released.

4.5.1.6 Next Cycle InitiationThe control system shall require an anti-repeat/anti-tie down feature so that eachbutton must be released, and reactivated, toinitiate the next cycle.

4.5.2 Control Interlock Circuit

4.5.2.1 Fail-Safe ControlControl interlock circuits shall be designedto operate in a fail-safe manner.

4.5.2.2 Operator InterventionControl interlock circuits shall inhibitautomatic or operator initiated actions whenall safe conditions are not met.

4.5.2.3 Machine SuspensionWhen safe conditions are not met controlinterlock circuits shall suspend further oradditional actions and shall notify theoperator of the suspended state of themachine.

4.5.2.4 Additional ActionsControl interlock circuits shall require theoperator to acknowledge the suspendedstate of the machine before additionalactions can take place.

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4.5.3 Emergency StopsEvery die casting machine shall have anemergency stop circuit using hardwarebased components. The emergency stopcircuit, when activated, shall override allother controls and cause all motion to stop.

4.5.3.1 Unobstructed Emergency Stop Device

Each die casting machine operator controlstation shall be provided with a readilyaccessible, unobstructed emergency stopdevice.

4.5.3.2 Emergency Stop Button Design

Pushbuttons that activate an emergency stopcircuit shall be red and unguarded, and shallhave a yellow background. Emergency stoppushbuttons shall be palm or mushroomhead type. All emergency stop pushbuttonsshall be of the type requiring manualresetting.

4.5.3.3 Emergency Stop Button Restrictions

Red palm type or red mushroom head typepushbuttons shall not be used for anyfunction except emergency stop.

4.5.3.4 Start-Up ProcedureFollowing an emergency stop, restartingoperation shall require a deliberate action tofollow a prescribed start-up procedureoutside the safeguarded space.

4.5.4 Power SourceThe power source of the die casting machineshall be clearly identified and shall beprovided with electrical disconnect andlockout for the purpose of maintenance orrepair of the die casting machine or itsancillary equipment.

4.5.5 Power LossSafeguards shall be implemented to ensurethat a loss of power shall not result in anoperator hazard. Safeguards must bedesigned to ensure that a loss of power shallproduce an emergency stop condition thatshall immediately de-energize allequipment that is potentially hazardous inthe die casting area.

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4.5.6 Electrical RequirementsNew die casting machines shall be built inaccordance with NFPA 79-1997.

4.6 Hydraulic Fluids andCompressed Gases

4.6.1 NitrogenMachines and systems that requirecompressed nitrogen shall be designed inaccordance with applicable industrystandards.

4.6.2 AirMachines and systems that requirecompressed air shall be designed inaccordance with applicable industrystandards.

4.6.3 Hose and TubingAll hoses and tubing that transport gasesand fluids that can produce potential hazardsshall be restrained in accordance withapplicable industry standards.

4.6.4 AccumulatorsHydraulic accumulators shall be properlyrestrained and charged in accordance withmanufacturer specifications. Chargedaccumulators shall be identified withappropriate signage for high pressurepotential hazard.

Barrier type piston accumulator systemsshall have a device that automaticallyremoves all stored hydraulic energy in acontrolled manner when electrical or controlpower is removed.

All other accumulator systems shall have alockable manual energy isolating device thatblocks all stored hydraulic energy.

4.6.5 Hydraulic FluidsHydraulic fluids used by the die castingmachine and its ancillary equipment shallcomply with ANSI/NFPA T2.13.8-97requirements for Group I or Group II.

E4.6.5 Hydraulic FluidsFlame retarding hydraulic fluids shouldconform to local, state, federal and industryrequirements, such as, but not limited to,OSHA, ANSI Standards, National FluidPower Association (NFPA), and FactoryMutual Research Corporation, (FMRC).

E4.6.3 Hose and TubingAn example of a restraint for hose ortubing is a mechanical clamp located toprevent “whipping” of loose hose ortubing. A mechanical restraint should beconstructed to prevent premature hosewear and failure.

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4.7 Manual ModeAll motions in manual mode shall be limitedto a maximum speed that is less than fullmachine speed. Any motion that creates ahazard within the operator’s reach in manualmode shall be controlled with two-handcontrol device. See Clause 4.5.1.

4.8 Safety SignsAll new signs shall conform to the color,format, size, and content requirements of theANSI Z535 series, where feasible.

CLAUSE 5: DIE REQUIREMENTS

5.1 Design, Construction, and UseDie hazards that shall be safeguardedinclude the following:1. Burn hazards associated with die spitting

and hot surfaces.2. Impact and pinch points associated with

die motion, ejection motion, core motion,and broken parts.

5.1.1 SizeDies shall fit within the guarding provided onthe machine or machine cell.

5.1.2 Broken PartsDies shall be guarded to prevent injury frombroken parts and/or springs. Dies equippedwith springs containing potential energyshall be equipped with signs.

5.1.3 WeightDie weight shall be permanently indicated onthe die to safeguard against overloading diehandling equipment.

5.1.4 MountingDie fastening provisions shall be made inboth die halves for securely mounting the dieto the platens.

5.1.5 HandlingDie casting dies and accessories shall haveprovisions to facilitate handling.

E5.1.2 Broken PartsSome ejector and core pull systems containsprings, which may fail after extended usage.To protect against such failure, resulting inpart of the mechanism becoming a flyingprojectile, guards should be provided over allsuch mechanisms.

E5.1.5 HandlingMetal straps should be provided to hold bothhalves of the die together duringtransportation. Provisions for lifting thehalves of the die should be provided.

E4.7 Manual ModeMaximum speed is to be based onapplication; maximum safe recommendedspeed for Manual Mode is 250 mm/sec(10in/sec).

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5.2 Die SettingImpact and pinch point hazards associatedwith die setting and handling shall besafeguarded.

The employer shall establish procedures forthe installation and removal of dies from thedie casting machine. The safeguardingprocedure shall include, lockout/tagoutprogram, selection and use of die handlingequipment, and selection and use ofpersonnel safety equipment.

5.3 Flash or Die SpittingIntentional flashing of a die for whateverreason is an unsafe practice and shall beprohibited.

5.4 Die Changing SystemWhen a die changing system is used inconjunction with a die casting machine, it ispermissible for motion to occur in the diearea with the machine doors and/or guardsopen or removed only if and when thefollowing conditions are met.1. A key operated selector switch is provided

to enable the die changing process.2. If the die changer is mobile, it shall act as

a barrier to the die area, replacing theopened or removed gate and/or guardwhen in position. The mobile unit shallinclude an electrical interlock, pluggedinto the machine when the unit is inposition. This interlock permits the diechanging process to be functional.

3. If the die changer is fixed, it shall act as abarrier to the die area, essentiallyreplacing the opened or removed gateand/or guard.

4. If the die changer, mobile or fixed, doesnot act as a barrier to the die area, theninterlocked perimeter guarding shall beused to guard the die area and the diechanging system.

E5.3 Flash or Die SpittingOver the life of the die, some spitting of thedie may occur. The parting line should beguarded to prevent burn hazards from spittingmetal.Vents used for air to escape during fillingshould be guarded or directed away from theoperator.

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CLAUSE 6: SYSTEM REQUIREMENTS

6.1 Ancillary EquipmentThe installation and use of any ancillaryequipment shall not reduce the level ofsafety embodied in this standard.

This standard describes the use of ancillaryequipment in conjunction with a die castingmachine. It is not intended to define thedesign and construction of ancillaryequipment.

All ancillary equipment shall be interlockedto achieve safe, controlled operation and toprevent hazardous motion when the diecasting machine is not in a predeterminedready state.

Any die casting machine safety device that isremoved or altered for the use of ancillaryequipment shall be replaced by one or moreof the following: modified guard, additionalguarding, presence sensing devices, orperimeter guarding. These additional safetydevices shall comply with the safeguardrequirements described in Clause 4.0.

6.1.1 Metal Delivery SystemWhen using a metal delivery system, thereshall be a perimeter guard designed toprevent burn hazards based on thetemperature, velocity, and quantity of metalbeing handled. All access safeguards shallbe interlocked to stop hazardous motion ofboth the metal delivery system and the diecasting machine.

6.1.2 Plunger Lubrication SystemSafeguards shall be used to avoid pinchpoint, collision, burn, and other hazardswhen a plunger lubrication system is used.

If combustible liquids are used, protectivemeasures shall be taken to prevent thespraying of combustible liquids on exposedmetal baths and heat sources in the event ofa hose or pipe failure.

E6.1.1 Metal Delivery SystemThe following are examples of metal deliverysystems:1. Automatic ladle.2. Metal pump.3. Metal siphon.4. Robotic ladle.5. Gooseneck.This list is not all inclusive of metal deliverysystems.

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6.1.3 Die Lubrication SystemSafeguards shall be used to avoid pinchpoint, collision, burn, and other hazardswhen a die lubrication system is used.

If combustible liquids are used, protectivemeasures shall be taken to prevent thespraying of combustible liquids on exposedmetal baths and heat sources in the event ofdelivery hose or pipe failure.

One of the following conditions shall beachieved prior to activation of a dielubrication system:1. The rear guard and operator's door shall

be closed. 2. Perimeter guarding shall be in place.3. Motion shall be controlled through two-

hand control. The two-hand control shallbe located in a position, which provides aclear line of sight to the die space.

6.1.4 Casting Extraction SystemSafeguards shall be used to avoid pinchpoint, collision, burn, and other hazardswhen a casting extraction system is used.

If combustible liquids are used, protectivemeasures shall be taken to prevent thespraying of combustible liquids on exposedmetal baths and heat sources in the event ofa hose or pipe failure.

One of the following conditions shall beachieved prior to activation of a castingextraction system:1. Perimeter guarding shall be in place.2. Motion shall be controlled through two-

hand control. The two-hand control shallbe located in a position, which provides aclear line of sight to the die space.

6.2 Emergency Stop CircuitryThe emergency stop circuitry shall behardwired and act independently from theelectronic control systems.

All ancillary equipment shall have ahardwired emergency stop circuit connectedin series with the die casting machineemergency stop circuit.

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6.3 Control Interlocks

6.3.1 Timers Timers shall not be used in conjunction withinterlocks to control the die casting machineor ancillary equipment during automatic orsemi-automatic operation.

6.3.2 Interlock ResetsResetting the die casting machine shall notautomatically reset ancillary equipment.

CLAUSE 7: USER REQUIREMENTS

7.1 TrainingThe employer shall train and instructpersonnel in the safe operation andmaintenance of the die casting machine andancillary equipment.

7.2 Lockout/TagoutThe employer shall establish a program andprocedure for affixing lockout or tagoutdevices.7.3 Risk AssessmentThe employer shall perform a riskassessment on die casting machines andancillary equipment to determine thesafeguarding necessary to achieve andmaintain a safe work environment.

7.4 Work AreaThe employer shall provide adequate workareas for safe operation of machines,maintenance, and material handling. Allwalkways and working surfaces shall be keptin good condition and free from debris andfluids.

7.5 Personal Protective EquipmentThe employer shall establish a personalprotective equipment program for personalsafety. Safety equipment selected as a resultof risk assessment shall be appropriate forthe task to be performed and in compliancewith applicable state, federal, and ANSIstandards.

E7.1 TrainingThe employer should document training andassessment of personnel.

E7.2 Lockout/TagoutThe isolating devices shall disable machinescomponents and other equipment to preventunexpected start-up or release of stored energy.

E7.5 Personal Protective Equipment

The Personal Protective Equipment program shouldinclude, but not be limited to, these types ofequipment:1. Eye protection.2. Hand protection.3. Body protection.4. Foot protection.5. Hearing protection.

E6.3.1 TimersTimers should not be used to delay or initiatemotion of an interlocked guard.

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7.6 VentilationA means of ventilation shall be provided tovent hazardous vapors away from workareas.

CLAUSE 8: MAINTENANCEREQUIREMENTS

8.1 TrainingThe employer shall train and instructpersonnel in the safe operation andmaintenance of the die casting machine andits ancillary equipment.

Maintenance personnel shall be trained onthe electrical, hydraulic, and pneumaticsystems. Training shall include mechanicaloperation of the die casting machine andancillary equipment through on the jobtraining or specialized training.

8.2 Lockout/TagoutThe employer shall establish a program andprocedure for affixing lockout/tagoutdevices.

8.3 Maintenance Operations While Under PowerWhen motion of the die casting machine isrequired for maintenance, it shall occur inmanual mode at a speed that is less than fullmachine speed. Any motion that creates ahazard within the operator’s reach in manualmode shall be controlled with a two-handcontrol device.

8.4 Stuck Plunger – Cold ChamberMachine

When freeing a stuck plunger in a coldchamber die casting machine, maintenancepersonnel shall not enter the die spaceunless the die casting machine is locked out;see Clause 7.2.

If die casting machine motion is required, seeClause 8.3.

8.5 Stuck CastingWhen freeing a stuck casting, personnelshall not enter the die space unless the die

E8.3 Maintenance OperationsWhile Under Power

Maximum speed is to be based onapplication; maximum safe recommendedspeed for Manual Mode is 250 mm/sec (10in/sec).

E8.2 Lockout/TagoutSee E7.2.

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casting machine is locked out. If die castingmachine motion is required, see Clause 8.3.

CLAUSE 9: GENERAL INFORMATION

9.1 Equipment IdentificationThe following indications shall be clearly anddurably attached to the die casting machine:1. Name and address of manufacturer.2. Type of machine.3. Serial number/machine number.4. Year of manufacture.5. Electrical characteristics.6. Weight.7. Safety Signage.

9.2 Machine ManualThe manufacturer or remanufacturer shallsupply a manual. The machine manual shallinclude the following information:1. Equipment Identification.2. Type of machine.3. Installation and transport weight.4. Intended use of the machine.5. Machine hazard identification.6. Safety instructions.7. Machine operating specifications.8. Operating Procedures.9. The prohibition of unauthorized

reconstruction and modification of themachine.

10. An instruction by the manufacturer thatonly personnel properly trained in theoperation, setup, and/or maintenance ofthe die casting machine, should beauthorized to operate the machine.

11. Alarm descriptions.12. Troubleshooting information.13. Recommended lockout procedures.

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ANNEXES

ANNEX A: COLD CHAMBER DIE CASTING MACHINE, TOP & SIDE VIEWANNEX B: HOT CHAMBER DIE CASTING MACHINE, TOP & SIDE VIEWANNEX C: VERTICAL DIE CASTING MACHINE, SIDE VIEWANNEX D: DIE AREA & DIE SPACE, TOP & SIDE VIEWANNEX E: TYPICAL DIE CASTING SYSTEM

Drawings have been simplified for clarity and are meantfor reference only within the context of this document.

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Documents

Die Cast Machine