Chapter 4 Overview

1
Chapter 4 Overview

• The DCM is very complex
• Mechanical, electrical, hydraulic and safety
  systems all work together
• Each system has many components
• Additional equipment may be used

2
Chapter 4 Objectives

• Using a quality photograph, correctly identify
  all structural components, electrical system
  components, hydraulic pump components, and safety
  devices
• Identify the purpose of all structural
  components, electrical system components,
  hydraulic pump components, and safety devices

3
New Term

• Solenoid
• An electromagnet that shifts a metal core

4
DCMs Systems

• Structural
• Electrical
• Hydraulic
• Safety

5
Structural Components

• Structural components framework
• DCM Base
• Support
• Shape is generally a rectangular box
• Usually extends under the entire DCM
• Rear portion enclosed to form a steel tank used
  as a reservoir for the hydraulic fluid/oil

6
Structural Platens

• 3 large plates that carry the DCM loads
• Rest on the DCM base
• Stationary at front of DCM
• Holds stationary die half on die space side
• Moving between stationary rear platen
• Moving/ejector half of die is mounted to it
• Rear at rear of DCM
• Slides back and forth as the tie bars stretch

7
StructuralTie bars

• 4 tie bars are long, round, solid beams
  mounted through four corners of platens
• Hold the DCM together
• Moving platen slides along the tie bars
• Size and strength of the tie bars determines the
  size of the DCM
• Some DCMs replaced tie bars with a solid frame
  made from a casting

8
Structural Toggle mechanism

• Connects rear and moving platens
• Acts as a lever and gains a mechanical advantage
  during die close and locking
• It overcame the deficiencies of using a large
  cylinder

9
Electrical Components

• Electrical energy powers and controls the DCM
• The electric power is converted to hydraulic
  energy in order to do the actual work of the DCM

10
Electrical Motor and Control Panel

• Electric motor(s) located at rear of DCM are
  directly coupled to the hydraulic pump
• Electrical energy is converted into hydraulic
  energy
• Pumps force oil into the hydraulic lines under
  pressure
• Pose electric shock hazard

11
Electrical Solenoids

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

12
Electrical Limit Switches

• Limit switches are the sensors, the eyes and
  ears, of the electrical control system
• Sense the position of doors, guards, cylinders
  and other moving components
• Maintenance is essential to the safe operation
  of the DCM
• Other types of switches and sensors, also

13
Hydraulic System

• DCM is operated by a hydraulic system
• A fluid, fire-resistant oil is used to power the
  cylinders that make the DCM move
• Operates at high pressures and high flow rates
• Hydraulic fluid is hot and can cause burns
• Repair/clean leaks and spills quickly

14
Hydraulic Hydraulic pumps

• DCM typically has two hydraulic pumps
• One pump capable of providing oil at high
  pressures but in low volumes
• A second pump capable of providing a high volume
  of oil at low pressures

15
Hydraulic Filters

• Filter(s) are required to keep the hydraulic
  fluid clean
• Located at the outlet of the pumps
• Require routine maintenance

16
Hydraulic Valves

• Used to control amount and direction of oil flow
• Solenoid-operated valves direct the flow to the
  head or rod side of a cylinder or direct oil to
  shift a large valve
• May be manually operated
• Series of valves mounted on a manifold may
  control the DCMs speed control

17
Hydraulic Heat Exchanger

• Operates similarly to a boiler
• Hot hydraulic oil and cooling water run through
  the heat exchanger the water cools the oil
• Leakage can be troublesome
• Hydraulic oil could be contaminated by water
• Cooling water could be contaminated by the
  hydraulic oil

18
HydraulicCylinders

• Open and close the DCM
• Inject the metal into the die
• Operate the ejection system
• Move slides on the die
• Actuate a safety ratchet and open and close a
  safety door at the die parting line

19
HydraulicInjection Components

• Inject the metal into the die
• Hot chamber components include
• Shot cylinder, plunger coupling, plunger, rings,
  gooseneck, bushing and nozzle

20
HydraulicInjection Components

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

21
HydraulicAccumulator

• A large steel tank
• Partially filled with hydraulic oil
• Above oil is high-pressure nitrogen gas
• Used when large volume of oil required

22
Hydraulic Intensifier

• Hydraulic device that increases hydraulic fluid
  pressure at end of injection stroke
• This high pressure dramatically increases the
  metal pressure to
• Squeeze additional metal into the die cavity as
  the metal shrinks
• Further compress trapped gases

23
Safety Components

• Die casting workplace has many hazards associated
  with it
• DCM operates with high pressures, high forces,
  and high voltages using liquid metal at high
  temperatures
• Need safety components and devices help ensure
  everyones safety

24
Safety cont.

• Die space area is protected by safety doors or
  gates
• Prevent access to this area when the DCM closes
• Guards at the toggle mechanism prevent access to
  mechanism when operating
• Safety ratchet prevents the DCM closing
• DCM will only close if safety conditions have
  been met and ratchet dog is withdrawn

25
Summary

• Structural system form the basis of the machine,
  providing support
• Electrical system provide power to the machine
  and control it
• Hydraulic system use a fluid, fire-resistant oil
  to power the cylinders that make DCM move
• Safety components help prevent injuries and
  accidents, when used appropriately and coupled
  with safety-conscious actions