safety unit 5 machine guarding

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"Ring test"

Good wheel portions will "ring" like a bell Cracks will sound "dead"

CPL (Compliance)- 2-1.25

If material is such a size and the operators hand are not closer than 4 inches, its considered a safe guard (not in standards)

hot forming machinery

put metal into furnace and got it red hot

stroking selector

supply a means of selecting OFF, INCH, SINGLE STROKE, or CONTINUOUS with the clutch/brake control

die

the complete tooling component used for cutting, forming, or assembling material within its point of operation

slide

- the main reciprocating press component member. may be called a ram, plunger, head, or platen

uses adjustable guards

-band saws

uses self adjustable guards

-mitre saws -jointer -table saws -circular saws -radial arm saws

Safety Trip Controls

Body Trip Bars Hand/Arm Trip Bars Tripwire Cables Positioning Critical Adjustment Critical Maintenance Critical Training Critical Manual Reset Needed Must Stop Machine Immediately

part revolution

Can disengage clutch at any point along the cycle

full revolution

Cannot disengage clutch until ONE complete stroke is made

roll formers and calendars

Machines which are capable of producing a bend across the width of a flat piece of metal by means of one or more rotating dies or rolls operated by safe interlock switch

press brakes

Metal working machine that forms parts through the use of dies attached to a plate ram or slide and a die bed. Primarily used to bend and form sheet metal but can also be used for punching, trimming, corrugating, and notching are the hardest machine to guard -their dies are not cutting, they are bending the shear

Gate 1. Type A 2. Type B

Movable barrier device which protects the operator at the point of operation before the machine cycle can be started; think of garage door; 2 types

Two-Hand Control

Needs Constant Pressure Needs Concurrent Pressure Positioning Critical Adjustment Critical Maintenance Critical Training Important Must Stop Machine Immediately

true

OSHA says flywheels 7 feet or less above the ground shall be guarded....

Presence-Sensing

Photoelectric Radiofrequency Electromechanical

Tongue guard

Prevent sparks and material from coming back around the wheel and out from the top 1/4''

Adjustable guards

Provides a barrier which may be adjusted to facilitate a variety of production operations Accommodate various sizes of stock May require additional operator training are typically used on

Self- adjusting guards

Provides a barrier which moves according to the size of the stock entering the danger area Accommodate various sizes of stock May require additional operator training

ANSI B11.10 Safety of Machinery- General Requirements and Risk Assessment

Risk assessment recommended and introduces concept of prevention through design

enclosure

Safeguarding by fixed physical barriers mounted on or around a machine to prevent access to the moving parts

point of operation

The area on a machine where material is positioned for processing or where work is actually being performed on the material

Two Hand Trips

Used of full revolution presses with anti-repeat features must be placed far enough from the point of operation to make it impossible for the operators to move their hands from the trip buttons into the point of operation before the first half of the cycle is completed

Restraint Devices

Uses Cables or Straps Affixes to Hands May Need Feeding Tools Adjustment Critical Positioning Critical Maintenance Critical Training Critical

Pullback Devices

Utilizes a series of cables attached to the operator's hands, wrists, and/or arms

belt sanders

finish stock by using a coated abrasive surface to remove material not much of a guard on them hard woods- dust exposure

Type B gate

gate comes down hits interlock switch and tells the machine go, the ram comes down. When the ram starts back up the ram goes back up with it; can ONLY be used on a part revolution

Type A gate

gate stays down entire cycle, and then the ram comes down and hits. After the ram goes back up, the gate will go back up; can be used on full and part revolution

1910.212

general requirements

Awareness Devices

generate a noticeable (distinctive by sound or intensity) audible or visual signal to warn of an approaching or present hazard

roll formers

go horizontal

calendars

go vertical

safe holding

going away from location

expanded metal

has to be 1/2'' holes so you can't get fingers in

spreader

helps reduce from pinching the blade

airline hydraulic cylinder

hydraulic

power transmission

includes all mechanical parts - such as gears, cams, shafts, pulley, belts clutches, brakes, and rods - that transmit energy and motion from a source of power to equipment or a machine

drill press

is a wood cutting machine that uses a multiple-cutting-edged rotating tool to remove wood and produce a hole in the stock

milling

is the machining process of bringing metal into contact with a rotating multi-edged cutter

hostage controls

keeps operator away from machine

"press"

means a mechanically or hydraulically powered machine that shears, punches, forms or assembles metal or other material by means of cutting, shaping, or combination dies attached to slides

Fly wheel

mechanical

reciprocating

moves left or right and north and south

Emergency Stop Devices

must remove all power to the entire machine and must be sustained until a full reset

continuous

no manual feeding

cold forming machinery

not heating the metal

uses interlock guards presence sensing

only on part revolution

1910.219

power transmission

uses fixed guards

power transmission

secondary operation

press machine operation in which a pre-worked part is further processed

stop control

provide a red STOP button with the clutch/brake control system

nip point

rollers=

Type C standards

standards are known as machinery-specific safety standards and contain guidelines that are germane to certain specific machine types

Type B standards

standards deal with safety aspects or safeguards that are applicable to many machine types

brake

the mechanism used on a mechanical power press component to stop and/or hold the slides, either directly or through a gear train, when the clutch is disengaged

antirepeat

the part of the clutch/brake control system designed to limit the press to a single stroke if the actuating means is held or stuck on operate

bolster plate

the plate attached to the top of the bed of the press component; it has drilled holes or T-slots for attaching the lower die or die shoes

feeding

the process of placing or removing material within or from the point of operation

blotter

thicker paper, to cushion the wheel for cutting

Type A standard

this standard identifies basic concepts, principles for design and general aspects that are applicable to all machinery

pedestal grinders, bench grinders and surface grinders

types of grinders

punch press

usually cold forming machinery

location

when a hazard is physically inaccessible under normal operating conditions or permitted only if the other precautionary restrictions can be met

guarding abrasive wheel

**Wheel guard DOES NOT have to protect the entire wheel

guard

A barrier designed for hazard control at the point of operation

true

ANSI says flywheels need to be 8 feet above ground should be guarded

jointers

face or flatten wood and are used primarily to joint small pieces of material done for edges

distance controls

3'' away from machine

table saws

A machine with a circular saw blade which is mounted under a table and only a portion of the blade extends above the table top mostly enclosed

device

A mechanism or control designed for safeguarding at the point of operation

mechanical shears

A metal working machine that is used primarily for shearing or cutting sheet metal Ram moves a nonrotary blade at a constant rate past the edge of fixed blade Can be mechanical or hydraulic with a full or part revolution clutch

Grinding machines

A metal working machine which uses an abrasive wheel against the metal surface causing a change in the surface or shape of the metal

mitre saws

A saw used to make accurate crosscuts and miters in a workpiece Used to an angle on wood -example: door trim Common in construction industry Majority of the time cross cutting is used

ANSI B11.19 Performance Criteria for Safeguarding

Addresses general safeguarding options such as guards, safeguarding devices, awareness devices as well as performance requirements for safe work procedures

safeguarding

Any means of preventing or controlling personnel from coming in contact with the moving parts of machinery or equipment that would potentially cause physical harm

radial arm saws

The operator cuts the wood stock by pulling the saw towards them usually cross cutting for the most part

safety blocks

They disconnect the clutch-and motor-control circuits when blocks are removed from their storage pockets

Complementary Equipment

devices or methods used to ensure or augment the proper operation of safeguarding

band saws

a saw consisting of a continuous band of metal with teeth that rides on two wheels can make curved cuts Horizontal are commonly used in metal work, will be using an oil or water based coolant to protect the saw

inch

an intermittent motion imparted to the slide (on machines using part-revolution clutches) by momentary operation of the inch-operating means. Operation of the inch-operating means engages the driving clutch so that a small portion of one stroke or indefinite stroking can occur, depending on the length of time the inch-operating means is operated; used by the die setter for setup of dies and tooling

primary operation

any preliminary press machine operation with material to be subsequently processed

Fixed guards

are a permanent part of the machine and not dependent upon moving parts to perform its intended function. Provides a barrier and is preferable to all other types of guards

Guards 1. Fixed guards 2. Interlocked guards 3. Adjustable guards 4. Self-Adjusting guards

are barriers which prevent access to danger areas, there are four general types:

Interlocked guards

are designed to automatically shut off or disengage the machine if the guard is opened or removed

lathes

are used for shaping round parts, such as table legs. Two types are used in the woodworking industry: manually operated or CNC operated First hazard- at the point of operation Chuck holds the part in place Coolant, oil or water will come down to cool the parts. If no cover, it will shoot out the coolant out on the floor or such and cause a hazard

planers

are woodworking machines used to dress and size rough-sawed lumber on one or more sides

cross cutting

cutting the wood in opposite way the grain is going

ripping

cutting the wood in the way of the grain on the wood, the wood can pinch and it could cause a kick back

Safeguarding Device

detects or prevents inadvertent access to a hazard


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