Transcript Machine Safety for Injection Molding

Machine Guarding
for Injection
Molding Machines
OSHA 10-Hour Outreach Training Program for the
Plastics Processing Industry
A Presentation of the SPI-OSHA Alliance
(Screen Capture of Website)
(Screen Capture of Website)
Course Objectives
• Identify the types of injuries that can occur
while operating injection molding machines
• Describe the possible causes of these injuries
• Identify ways to safely operate injection
molding machines
• Recognize the importance of a total safety
and health approach
(Screen Capture of Website)
Reasons to Focus on Injuries in
the Injection Molding Process
• High injury/illness rates
• OSHA citations
• National Emphasis Program
• Site-Specific Targeting
• High workers' compensation costs
Types of Injuries
• Fatalities
• Cuts and bruises
• Amputations
• Sprains and strains
• Avulsions
• Burns
• Fractures
• Electric shock
Some Causes of Injuries
• Reaching around, under, over or through
guards into hazardous areas
• Removing or bypassing guards
• Reaching into equipment to remove stuck or
jammed material
• Not using LOTO procedures
• Machine/equipment malfunctions
Causes of Injuries
(cont’d)
• Lack of recognition of job hazards
• Lack of familiarity with the equipment
• Inadequate training, comprehension, or both
• Operating machines with missing or
inoperable guards and improper or
inadequate machine maintenance
Injection Molding Machinery
• Horizontal injection
molding machine
(HIMM)
• Vertical injection
molding machine
(VIMM)
Vertical Injection Molding Machines
VIMMs
VIMMs
• Combinations of vertical and
horizontal clamp and injection
configurations of machines
• Regardless of the configuration
of the machine, basic machine
guarding and good safe work
practices must be applied
– Point of operation
– Other moving machine parts
VIMMs:
Unique Hazards and Issues
• Gravity
• Plastic splatter/missing insert
• Flying inserts
• Unexpected bystander
interventions
Horizontal Injection Molding
Machines - HIMMs
HIMMs:
Mechanical Hazards
• Point of operation
• Pinch points
• Nip points
• Rotating parts
Potential Injuries from
Mechanical Hazards
•
•
•
•
•
Fatalities
Amputations
Avulsions
Crushing injuries
Fractures
Safety Guards and Devices
• Types of guards and devices
– Movable guards with interlocks
– Fixed barrier guards
– Presence-sensing devices
– Mechanical safety bars
• Locations of guards
– Over/around moving equipment
– Around electrical hazards
– Around thermal hazards
Operator’s Gate
• Equipped with redundant
interlocks
– Electrical
– Hydraulic
– Mechanical safety bar
• Allows the machine to
operate only when the
gate is closed
Electrical Interlock
• Allows the electrical
system to operate and
close the clamp
• Actuated when the
operator’s gate is opened
or closed
• Prevents clamp from
closing when the
operator’s gate is open
Electrical Interlock Operation
Hydraulic Interlock
• Actuated by opening or
closing the operator’s
gate
• Each hydraulic IMM
requires at least one
• Prevents clamp from
closing when the
operator’s gate is open
Hydraulic Interlock Operation
Hydraulic Interlock Operation
Before Activation
After Activation
Mechanical Safety Device
• Prevents clamp from
closing when the
operator’s gate is open
• Must have at least one
mechanical device on all
IMMs
Mechanical Safety Device Operation
Other Guarding
• Rear guard
• Top guard
• Parts discharge
guard
• Feed opening guard
• Electrical system
guards
• Purge guard
• Injection barrel
cover
Rear Guard
• Prevents clamp from
closing when
interlocked rear guard
is opened
• Should have at least
two interlocks
• Prevents access to
mold areas
Top Guard
• Required if employees
can reach over the top of
the machine and into
hazardous areas
• Should be interlocked if
movable
Top Guards (cont’d)
Parts Discharge Guard
• Keeps employees
from reaching under
the operator’s gate
and into hazardous
areas
Purge Protection
• Covers the nozzle and
purging area
Purge guard
• In combination with PPE,
minimizes exposure to
molten plastic during purging
• Window allows observation
through purge guard, if
equipped
• Should be equipped with an
interlock
Safety
window
Barrel cover
Injection Barrel Cover
• Protects from exposure
to high voltage and high
temperatures
Grinder Guarding
Guarding by:
•Enclosure over moving
components
•Anti-kickback flaps in
feed throat
•Proximity guarding –
distance from feed chute
to rotating knives
Proximity
Guarding
Abrasive Wheel Machinery
Work rests on offhand grinding machines must be kept
adjusted closely to the wheel with a maximum opening
of 1/8-inch to prevent the work piece or tool from
being jammed between the wheel and the rest, which
may result in wheel breakage or wheel explosion.
Abrasive Wheel Machinery
The distance between the wheel periphery and the
adjustable tongue must never exceed 1/4-inch.
Power-Transmission Apparatus
Power-transmission
apparatus (shafting,
flywheels, pulleys, belts,
chain drives, etc.) less
than 7 feet from the floor
or working platform must
be guarded.
Unguarded belt
and pulley
Presence Sensing Devices
• Safety mat
• Light curtain
Safety Guards and Devices
Light Curtain
Presence Sensing Devices
Safety Mat
How to Protect Yourself
• Recognize the hazards in the job you are
doing
• Understand the requirements for
guarding machines
• Implement guarding solutions
Emergency Stop
Know:
• Where it is located
• What it controls
• When to use it
Signs and Warnings
Colors used with Safety Signs
have meaning!
DANGER
White Lettering/Red Background
WARNING
Black Lettering/Orange
Background
CAUTION
Black Lettering/Yellow
Background
High Voltage
Rotating Screw
High Temperature
High Pressure
Robots
• Used to automate
repetitive or
hazardous tasks
• Must be guarded to
prevent workers from
entering or reaching
into hazardous areas
The Robot
References for Injection Molding Safety
•ANSI/SPI B151.1- 1997 Horizontal Injection Molding
Machines - Safety Requirements for Manufacture, Care and
Use
•ANSI B11.19-2003 Performance Criteria for Safeguarding
ANSI Standards are available at the following web site:
www.ansi.org
OSHA's Site-Specific Targeting (SST) Program
OSHA's Site-Specific Targeting (SST) program selects for inspection
individual worksites with the nation's highest Days Away from Work Injury
and Illness (DAFWII) Case Rate and Days Away, Restricted, or Transferred
(DART) Rates. It is based on data reported by more than 80,000
employers surveyed by the agency.
See the OSHA Web site for the
most current directive and the
rates used to target inspections.
In order to verify the reliability of
claims by establishments that
they have achieved low DART
rates, OSHA inspects a certain
percentage of employers with low
rates.
OSHA National Emphasis Program on Amputations
On October 27, 2006, the Occupational Safety and Health Administration (OSHA)
revised its national emphasis program aimed at reducing amputations in general
industry workplaces. The National Emphasis Program on Amputations targets
all types of machinery and equipment that are considered a high risk for causing
amputations. The plastics processing industry is among the industries under
scrutiny for workplace amputations.
The twenty-four states and two territories which operate their own OSHA programs
are encouraged, but not required, to adopt a similar emphasis program. State Plan
State information is available on OSHA’s Web site. The OSHA directive on this
emphasis program is available on OSHA's Web site under Regulations and
Compliance, subcategory Compliance Directives, No. CPL 03-00-003.
Under this initiative, regional and area OSHA offices will continue to conduct
outreach; targeting and selection; and inspections. Area offices will obtain and use
additional data to identify and add establishments where serious injuries or fatalities
related to these machines have occurred.
The Job Safety Analysis Process
The Job Safety Analysis (JSA) process is a very
effective means of helping reduce incidents,
accidents, and injuries in the workplace. It is a
multi-step process.
•Basic Job Steps
•Potential Hazards
•Recommended Safe Job Procedures
Summary
• Injuries can occur while operating injection
molding machines
• Risk areas can be protected by safety guards
and devices
• Protect yourself and operate injection molding
machines safely
• Recognize the importance of a total safety
and health approach
Do you have any
Questions?