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Chapter 4 OverviewChapter 4 Overview

The DCM is very complexThe DCM is very complex• Mechanical, electrical, hydraulic and safety Mechanical, electrical, hydraulic and safety

systems all work together systems all work together Each system has many componentsEach system has many components Additional equipment may be used Additional equipment may be used

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Chapter 4 ObjectivesChapter 4 Objectives

Using a quality photograph, correctly identify Using a quality photograph, correctly identify all structural components, electrical system all structural components, electrical system components, hydraulic pump components, components, hydraulic pump components, and safety devicesand safety devices

Identify the purpose of all structural Identify the purpose of all structural components, electrical system components, components, electrical system components, hydraulic pump components, and safety hydraulic pump components, and safety devicesdevices

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New TermNew Term

SolenoidSolenoid• An electromagnet that shifts a metal core An electromagnet that shifts a metal core

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DCM’s SystemsDCM’s Systems

StructuralStructural ElectricalElectrical HydraulicHydraulic SafetySafety

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Structural ComponentsStructural Components

Structural components = framework Structural components = framework DCM BaseDCM Base

• Support Support • Shape is generally Shape is generally

a rectangular boxa rectangular box• Usually extends under Usually extends under

the entire DCMthe entire DCM• Rear portion enclosed Rear portion enclosed

to form a steel tank used to form a steel tank used as a reservoir for the as a reservoir for the hydraulic fluid/oil hydraulic fluid/oil

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Structural: Structural: PlatensPlatens 3 large plates that carry the DCM loads 3 large plates that carry the DCM loads Rest on the DCM baseRest on the DCM base Stationary: Stationary:

at front of DCMat front of DCM• Holds stationary die Holds stationary die

half on die space sidehalf on die space side Moving: between stationary & rear platenMoving: between stationary & rear platen

• Moving/ejector half of die is mounted to itMoving/ejector half of die is mounted to it Rear: at rear of DCMRear: at rear of DCM

• Slides back and forth as the tie bars stretchSlides back and forth as the tie bars stretch

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Structural:Structural:Tie barsTie bars

4 tie bars are long, 4 tie bars are long, round, solid beams round, solid beams mounted through four mounted through four corners of platens corners of platens

Hold the DCM together Hold the DCM together Moving platen slides along the tie barsMoving platen slides along the tie bars Size and strength of the tie bars determines the size of the Size and strength of the tie bars determines the size of the

DCMDCM Some DCM’s replaced tie bars with a solid frame made Some DCM’s replaced tie bars with a solid frame made

from a casting from a casting

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Structural: Structural: Toggle mechanismToggle mechanism

Connects rear and moving platens Connects rear and moving platens Acts as a lever and gains a mechanical Acts as a lever and gains a mechanical

advantage during die close and lockingadvantage during die close and locking It overcame the deficiencies of using a large It overcame the deficiencies of using a large

cylindercylinder

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Electrical ComponentsElectrical Components

Electrical energy powers and controls the Electrical energy powers and controls the DCMDCM

The electric power is converted to hydraulic The electric power is converted to hydraulic energy in order to do the actual work of the energy in order to do the actual work of the DCMDCM

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Electrical: Electrical: Motor and Control PanelMotor and Control Panel

Electric motor(s) located at rear of DCM are directly Electric motor(s) located at rear of DCM are directly coupled to the hydraulic pump coupled to the hydraulic pump

Electrical energy is converted into hydraulic energyElectrical energy is converted into hydraulic energy Pumps force oil into the Pumps force oil into the

hydraulic lines under pressure hydraulic lines under pressure Pose electric shock hazardPose electric shock hazard

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Electrical: Electrical: SolenoidsSolenoids

Shift the valves that control the volume and Shift the valves that control the volume and direction of hydraulic oil flowdirection of hydraulic oil flow

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Electrical: Electrical: Limit SwitchesLimit Switches

Limit switches are the sensors, the eyes and ears, of Limit switches are the sensors, the eyes and ears, of the electrical control systemthe electrical control system

Sense the position of doors, guards, cylinders and Sense the position of doors, guards, cylinders and other moving componentsother moving components

Maintenance is essential Maintenance is essential to the safe operation to the safe operation of the DCMof the DCM

Other types of switches Other types of switches and sensors, alsoand sensors, also

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Hydraulic SystemHydraulic System

DCM is operated by a hydraulic system DCM is operated by a hydraulic system • A fluid, fire-resistant oil is used to power the A fluid, fire-resistant oil is used to power the

cylinders that make the DCM movecylinders that make the DCM move• Operates at high pressures and high flow rates Operates at high pressures and high flow rates

Hydraulic fluid is hot and can cause burns Hydraulic fluid is hot and can cause burns • Repair/clean leaks and spills quickly Repair/clean leaks and spills quickly

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Hydraulic: Hydraulic: Hydraulic pumpsHydraulic pumps

DCM typically has two hydraulic pumpsDCM typically has two hydraulic pumps One pump capable of providing oil at high One pump capable of providing oil at high

pressures but in low volumespressures but in low volumes A second pump capable of providing a high volume A second pump capable of providing a high volume

of oil at low pressuresof oil at low pressures

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Hydraulic: Hydraulic: FiltersFilters

Filter(s) are required to keep the hydraulic Filter(s) are required to keep the hydraulic fluid cleanfluid clean• Located at the outlet of the pumpsLocated at the outlet of the pumps

Require routine maintenanceRequire routine maintenance

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Hydraulic: Hydraulic: ValvesValves

Used to control amount and direction of oil flowUsed to control amount and direction of oil flow• Solenoid-operated valves direct the flow to the head or Solenoid-operated valves direct the flow to the head or

rod side of a cylinder or direct oil to shift a large valverod side of a cylinder or direct oil to shift a large valve May be manually operatedMay be manually operated Series of valves mounted on a manifold may control Series of valves mounted on a manifold may control

the DCM’s speed controlthe DCM’s speed control

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Hydraulic: Hydraulic: Heat ExchangerHeat Exchanger

Operates similarly to a boilerOperates similarly to a boiler• Hot hydraulic oil and cooling water run through the heat Hot hydraulic oil and cooling water run through the heat

exchanger; the water cools the oilexchanger; the water cools the oil Leakage can be troublesomeLeakage can be troublesome

• Hydraulic oil could be contaminated by waterHydraulic oil could be contaminated by water• Cooling water could be contaminated by the hydraulic oilCooling water could be contaminated by the hydraulic oil

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Hydraulic:Hydraulic:CylindersCylinders

Open and close the DCMOpen and close the DCM Inject the metal into the dieInject the metal into the die Operate the ejection systemOperate the ejection system Move slides on the dieMove slides on the die Actuate a safety ratchet and open and close Actuate a safety ratchet and open and close

a safety door at the die parting line a safety door at the die parting line

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Hydraulic:Hydraulic:Injection ComponentsInjection Components

Inject the metal Inject the metal into the dieinto the die

Hot chamber Hot chamber components include:components include:• Shot cylinder, plunger Shot cylinder, plunger

coupling, plunger, rings, coupling, plunger, rings, gooseneck, bushing gooseneck, bushing and nozzleand nozzle

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Hydraulic:Hydraulic:Injection ComponentsInjection Components

Cold chamber components include:Cold chamber components include:• Shot cylinder, plunger rod and tip, coupling and the cold Shot cylinder, plunger rod and tip, coupling and the cold

chamber chamber

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Hydraulic:Hydraulic:AccumulatorAccumulator

A large steel tankA large steel tank Partially filled with Partially filled with

hydraulic oilhydraulic oil Above oil is high-Above oil is high-

pressure nitrogen gaspressure nitrogen gas Used when large Used when large

volume of oil required volume of oil required

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Hydraulic: Hydraulic: IntensifierIntensifier

Hydraulic device that increases hydraulic fluid Hydraulic device that increases hydraulic fluid pressure at end of injection stroke pressure at end of injection stroke

This high pressure dramatically increases the metal This high pressure dramatically increases the metal pressure to:pressure to:• Squeeze additional metal Squeeze additional metal

into the die cavity as the into the die cavity as the metal shrinksmetal shrinks

• Further compress Further compress trapped gasestrapped gases

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Safety ComponentsSafety Components

Die casting workplace has many hazards Die casting workplace has many hazards associated with itassociated with it

DCM operates with high pressures, high DCM operates with high pressures, high forces, and high voltages using liquid metal forces, and high voltages using liquid metal at high temperaturesat high temperatures

Need safety components and devices help Need safety components and devices help ensure everyone’s safetyensure everyone’s safety

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Safety Safety cont.cont.

Die space area is protected by safety doors Die space area is protected by safety doors or gates or gates • Prevent access to this area when the DCM closesPrevent access to this area when the DCM closes

Guards at the toggle mechanism prevent Guards at the toggle mechanism prevent access to mechanism when operatingaccess to mechanism when operating

Safety ratchet prevents the DCM closing Safety ratchet prevents the DCM closing • DCM will only close if safety conditions have DCM will only close if safety conditions have

been met and ratchet dog is withdrawnbeen met and ratchet dog is withdrawn

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SummarySummary

Structural system form the basis of the machine, Structural system form the basis of the machine, providing supportproviding support

Electrical system provide power to the machine Electrical system provide power to the machine and control itand control it

Hydraulic system use a fluid, fire-resistant oil to Hydraulic system use a fluid, fire-resistant oil to power the cylinders that make DCM movepower the cylinders that make DCM move

Safety components help prevent injuries and Safety components help prevent injuries and accidents, when used appropriately and coupled accidents, when used appropriately and coupled with safety-conscious actionswith safety-conscious actions