Wheels, Tires & Hubs

Heavy Equipment Technician

First Period

Module 190102d

Suspension, Wheels and Systems

Wheels, Tires and Hubs

Identify common wheel types and

mounting designs..

Explain tire construction, care and

maintenance in relation to design..

State the safety procedures required

when handling tires and wheels..

Objectives

1.

2.

3.

Objectives

4.

5.

6.

Perform wheel removal, inspection

and installation..

Explain wheel balancing..

Diagnose wheel and tire faults.

Objective One

Identify common wheel types and mounting

designs.

Spoke wheels are

mounted with two

bearings on the axle

shaft, and may have three, five or six spokes..

Spoke Wheels:

Wheel Types:

The brake drum is bolted to the spider.

Brake

Drum

Spoke

WheelA spoke wheel is a

heavy casting, and

may be called a spider

or a Dayton Wheel..

Multi piece rims are

typically composed

of a rim base, a solid

continuous side ring

and a split lock ring..

Wheel Types:

Rim Base

Split Lock

Ring

Continuous Side

Ring

Rim Clamp &

NutSometimes referred to

as a de-mountable rim.

Spoke Wheels:

Wheel Types:

Brake Drum

Spoke

Wheel

Rim Base

Split Lock Ring

Continuous

Side Ring

Rim Clamp & Nut

Rim and tire assembly

are attached to the

spider studs by wedge

shaped clamps and

nuts.

Spoke Wheels:

When dual tires are

located on one wheel, a

spacer is used in

between the two tires to

prevent them from

contacting each other.

Wheel Types:

Spoke Wheels:

Spacer

May have a sight glass

and lubricant filler plug

on a non driving wheel..

Corrugated

SpacerCorrugated

Channel Spacer

Spacer Types

Wheel Types:

Spacer width adjusts the depth of rim clamps.

Ensure that a minimum of two to three threads

passes the face of the retaining nut.

Spoke Wheels:

Disc wheels are composed

of a rim and disc that are

welded together, and may

use a removable side ring

and locking ring, for easier

tire assembly..

Wheel Types:

Also known as a Bud wheel.

Usually uses tubeless tires.

Disc Wheels:

Inboard Brake Drum Wheel Types:

The hub is separate

from the wheel,

unlike the spoke

wheel’s hub which

is part of the wheel.

Disc Wheels:

Wheel

Bearings

Wheel

Hub

Wheel

Hub Seal

Adjusting

Nut

Spindle

Brake

Drum

Washer

Disc Wheel

Stud BoltAn inboard Brake

Drum mounting is

located to the rear

of the wheel hub.

Outboard Brake Drum Wheel Types:

Disc Wheels:

Wheel Bearings

Wheel

Hub

Wheel

Hub Seal

Adjusting

NutSpindle

Brak

e

Drum

Washer

Disc

Wheel

Stud BoltAn Outboard Brake

Drum mounting is

located at the front

of the wheel hub.

Stud piloted disc wheels have

cone shaped recessed stud

holes, and the hub is mounted

and centered by the studs and

cone shaped wheel nuts..

Wheel Types:

Stud Piloted Disc Wheels:

Wheel Nut

Head Type

Wheel

Stud

It is critical that the tapered

portion of the nut enters the

tapered stud hole of the disc

wheel, or the wheel will come

loose.

Taper

When dual wheels are

used, a special nut is

required to secure the

inside wheel and provide

a threaded surface for

the outer wheel nut..

The special nut has two

tapered shoulders to center the inner wheel and

outer wheel, and is also threaded to act as a

stud for the outer wheel and nut.

Inner

Wheel

Hub

Wheel Types:

Stud Piloted Disc Wheels:

Taper

Taper

Uses the center section of

the hub itself, to center the

wheel or wheels..

Wheel Types:

Hub Piloted Disc Wheels:

Flange

Nut

Body

Nut Threads

Hub

Disc Wheels

The nuts are for clamping

the wheel to hub only.

Use proper hardware for mounting wheels.

Stud Piloted

Wheels

Hub Piloted

Wheel

Cone Nut HubFlange

Nut

Wheel Types:

Caution:

Stud Piloted

Wheel

Aluminum wheels are thicker and need

longer mounting studs.

Hub

Objective Two

Explain tire construction, care and

maintenance in relation to design

Tube type tire installations can involve many

components as well as multi-piece rims,

matching of component parts is critical.

Tube Type Tires

Locking

Ring

Side Ring

Disc

Wheel

Flap

Tube &

Valve Stem Tire

Tubeless Type Tires

Disc Wheel

& Valve

Stem

Tire

Fewer parts simplifies tire

installation, reduced

service time (required for

careful matching of wheel

and rim components) which

reduces cost.

Very common.

Tread Breakers

Inner

Tube

Cord

Body

Flap

Rim Assembly

Side

Walls

Tube Type Tires

Off-road Tires:

Off-road tires, either

tube or tubeless, are

designed to withstand

heavy loads and shocks

during operation..

Breakers may be made

of shredded steel for

added puncture

protection and strength.

Tread Breakers

Cord Body

Bead

Rim Side

Walls

Tube Type Tires

Off-road Tires:

Inner

Flange

Outer

FlangeO-ring

Seal

Bead

Seat

Band

Off-road tires may

travel at relatively

low speeds as

compared to an

on-road tire, but

their cargo weight is

enormous..

Off-road Tires

Caterpillar 797 truck carries 360 tons of payload

plus the weight of the truck, for a total of about

615 tons on 6 tires.

Tires for motor grader application may have the

same tread design for steering and traction.

Front tires treads may be mounted in the

opposite direction to the rear, for steering

stability.

Directional tires (usually identified by direction

of rotation arrow) are often used for better

traction as well as their self cleaning tread

ability..

Off-road Tires

Some equipment may use solid type tires,

where ride quality is not as important as load

carrying capacity.

Solid Type Tires

Tire Tread Design

On-highway steering and trailer axles usually

use the rib design, while most driving axles

use the block design, because of its better

traction ability..

Rib

Design

Block

Design

Tread design is basically for traction under

different conditions, such as rain, snow and

mud etc..

Tire Tread Design

With new technology in tire design, compound

mixtures and tread designs are becoming very

specialized, especially in the automotive area,

but is also spinning off into the on-highway

heavy duty truck area.

Tire Construction

Two types of tire construction:

Bias Ply Tire

Radial Tire

1.

2.

Have internal plies or cords

overlapping at an angle,

which makes for a strong

but stiff tire.

The plies or cords are made of rayon, nylon or

polyester, the casing or body is made of natural

or synthetic rubber and a bead of steel cable.

Bias Ply Tire:

The number of plies or

cords give the tire its load

carrying capacity. Cords

The ply arrangement is

the same in the sidewall

as well as the tread area.

Thickness of plies in the

sidewall causes friction

movement within the

plies, which builds up

heat, eventually resulting

in tire failure.

Bead Side

Wall

Plies

Tread

Bias Ply Tire:

The stiffness of a bias ply allows for little or no

sidewall flexing.

This lack of flexing may

cause the loss of tread

contact with the road

causing instability and

loss of traction.

Bias Ply Tire:

Bias ply tires are best suited for low speed and lower load operation.

Radial ply tires use steel in

the body cords (plies) and

steel reinforcing belts..

Steel belts help to protect

the tire from road hazards.

The plies are laid at 90° to

the bead, for good flexibility..

Radial Ply Tire:

Tire Construction

Reinforcing Belts

Tire Casing

Minimum movement

between the plies

generates less heat.

Radial Ply Tire:

Bead

Plies

Belts Tread

Flexibility

The flexibility in the

sidewall of the tire

also allows for better

traction and control.

Advantages:

Less rolling resistance increases fuel

economy.

Reduces shock loads, resulting in less wear

on steering components and enhances ride

quality.

Higher speed and load capability.

Less repair costs due to puncture resistance.

Radial Ply Tire:

Advantages:

Tire Sizing

Tire size 10.00R20

10.00 is the Section

Width of the tire in

inches..

20 is the rim

diameter in inches

that the tire fits on.

Single Tires:

Tire Matching

Matching tires increases

tire life.

It reducing uneven

loading and steering

problems, such as

pulling to one side.

Tire manufactures allow a maximum difference

in size on the same axle of:

Tire Matching

A B A B

Maximum Circumference

Difference

A – B = ¾” (19.1 mm)

Maximum Diameter

Difference

A – B = ¼” (6.4 mm)

Dual Tires:

Tire Matching

When the same axle has a dual tire arrangement the sizing is also critical..

The specifications for dual tires is the same as for single tires..

Straight Edge

Dual Tires:

Tire Matching

String Gauge

Remove weight off

the tires to ensure

accuracy..

If vehicle load is

evenly distributed,

matching tires

ensures equal tire

loading and longevity.

On a four wheel axle assembly, if a single tire

is larger than the others (but still within

allowable limits), install largest tire on outside

wheel to compensates for crown of the road.

Exaggerated

Dual Tires:

Tire Matching

Tire Care

Under-

inflation

Over-

inflation

Under-inflation:

Over-inflation:

Causes abnormal tire

deflection, heat build-up and

tire shoulder wear..

Causes harsher ride, transmits

more shock loads to steering

and suspension components,

and tire centre wear.

Tire Care

Proper

Inflation

Results in proper tire to

road contact for traction,

braking, safety and

even tire wear..

Proper Inflation:

Caution

Ensure a clean and dry air supply for inflation,

to prevent internal wheel and tire damage.

Tire Care

Tire Rotation:

Extends tire life..

Follow manufacturers

recommended pattern.

Washing tire will make

inspection easier, and

also removes dirt, oil,

and grease, preventing

rubber deterioration..

Objective Three

State the safety procedures required when

handling tires and wheels.

Potential paths for explosive forces.

Safety Precautions

Release all air from the tire, before removing

side ring, lock ring, or a tire assembly from

a vehicle, for service work.

Safety Precautions

Release tire air pressure by the valve core to

approximately 40 psi, then remove valve

core.In cold temperatures, moist air may freeze

the valve stem opening closed, ensure no

air pressure by inserting a wire into the

valve stem.

Disassemble wheel/rim assembly as per

manufacturer’s instruction, using proper tools

to prevent personal injury and damage.

Safety Precautions

Sprung

Side

Ring

Cracks

Broken

Side Ring Wheel Nut Damage

Clean components and visually inspect tire, rim,

wheel and mounting components for signs of

overheating, cracks, distortion and damage.

Safety Precautions

Following manufacturer’s instructions regarding

matching parts, ensure use of proper

pieces that match rim.

Always use a safety cage.

Safety Precautions

Visually inspect to ensure that the tire beads

and side ring or lock ring are properly seated.

Use a clip-on air chuck on

an extended hose with a

remote inflate/deflate

mechanism when inflating

a tire, in case deflation is

necessary.

Never add air to a tire that was run while flat, or

at 80% or less of recommended air pressure..

It Must be disassembled and inspected

for damage..

Never assemble mismatched tires and wheel /

rim assemblies.

Never hammer or pry on any type of tire that

is partially inflated..

Safety Rules

Safety Rules

Lubricate tire and rim assembly with rubber

lubricant, and with no valve core in the valve’s

stem, inflate tire to maximum of 40 psi pressure..

If tire bead does not seat, deflate tire .. unseat

bead .. apply lubricant .. square up tire .. retry..

Off-load inflated tires with care, damaged

components may cause the assembly to fly apart.

Safety Rules

1. Loosenin

g the

bead.

2. Forcing the

bead into

the rim

well.

3. Prying the

rim out of

the tire.

4. Valve stem

installation.

Work the

lower bead onto the

rim.

Work the

upper bead onto the rim.

Safety Rules

5.

6.

Valve Stem

Rim

Safety Rules

Bead breaking equipment

is easier and safer when

servicing a rim attached

to the machine..

In off-road applications the

rim may have more

components, so matching

parts correctly is critical.

Safety Rules

When removing and

installing tires, smooth

clean tools prevent rim

and tire damage..

Work carefully when

installing side rings and

lock rings..

Safety Rules

Always use a restraining

device when removing the

tire.

Cleanliness prevents

abrasive materials

entering the tire and

reducing tire life..

Use lubricant when

installing tire..

Safety Rules

Cross section of a five piece rim assembly.

Locator – Demountable Rim Only

Lock Ring Driver

Gutter Notch for

Lock Ring Driver

5° Bead Seat

Band, Taper Ring

Tubeless Valve Hole

Lock Ring

Pry Bar

Slot

Flanges

(Side

Ring)

O-ring

Gasket

Bead

Seat

Band Toe

Rim Base

Occupational Health and Safety Regulations

General Hazard Requirements Document

Read it

Safety Rules

Objective Four

Perform wheel removal, inspection and

installation

Wheel hubs are

supported by two

wheel bearings..

Axle Hub Mounting

Steering axles and

trailer axles are usually dead axles.

The wheel hub rotates

around a stationary

spindle that is

attached to the axle..

Dead Axle:Disc

Wheel

Wheel

Nut

Wheel

Stud

Hub

Hub

Cap

Brake

Drum

Outer

Wheel

Bearing

Inner

Wheel

Bearing

Axle

Spindle

Live Axle Hub Mounting

Outer Wheel Nut Wheel Stud

Hub

Axle Shaft

Brake Drum

Axle Housing

Inner Wheel

Drive Axle Stud

Live axles are usually drive axles..

Outer Wheel

Outer Wheel

Bearing

Inner Wheel

Bearing

Inner Wheel

Bearing

Hub

Axle

Shaft Housing

Outer Wheel

Bearing

The hub is supported by two wheel bearings

that rotate on the axle housing..

The hub is driven by the axle shaft, through

the center of the axle housing.

Spindle

Live Axle Hub Mounting

Axle

A removable brake

drum style of axle hub,

with drum pilot and

wheel pilot notches..

Axle Hub Removal

Wheel

Pilot

Drum

Pilot

Wear proper breathing

mask, the brake dust

may contain asbestos.

Hub and bearings must be kept free of dust,

dirt, and lubricated properly when installing.

Pilot Pad

Most axle shafts are retained by split tapered

dowel wedges, Do Not remove nuts until

dowel wedges are loose.

Dowel Wedge

Flat

Washer

Nut Axle Shaft Flange

Clearance

Axle Hub Removal

To remove the axle shaft, first loosen all axle

shaft nuts only a few turns..

Axle Hub Removal

Strike the center of the axle shaft with a

large hammer and drift to loosen the tapered

dowels, then remove nuts, dowels and axle.

Axle Shaft Nuts

1.

2.

Inspect all parts

for serviceability..

Brake Drum

Mounting

Studs

Axle Shaft

Mounting Studs

Hub cleanliness

is essential for

component

longevity..

Axle Hub Inspection

Stud Nut

Install lubricated bearing assembly and seal in

the hub, to prepare for installation onto the

axle housing spindle.

Axle Hub Inspection

Shiny spots on spindle’s

bearing mounting surface

may be caused by bearing

creep..

Normally bearing creep allows the bearing’s

inner ring to slowly turn on the spindle to

prevent spot loading of the bearing.

Clean all spindle mounted

parts with non-petroleum

based product..

Axle Hub Inspection

Clean and inspect bearings for spalling

before reusing.

Spalling damage.

Crack damage

may be caused

by improper stud

installation.

Axle Hub Inspection

The ends of the studs may be stamped with

“L” or “R”, to designate left or right hand thread.

Crack

When wheel studs break in

service, its usually because

of over tightening.

Always replace the studs

on either side of the broken

stud as well.

Replace

When replacing wheel studs,

ensure proper length, style

and thread direction.

Serrations

Clipped

Head

Axle Hub Inspection

Using proper steel

tools, install lubricated

bearing cup, and seal

in the right direction.

Axle Hub Installation

Outrunner

Handle

Outrunner

Adapter

Plate

Bearing

Centering

Tool

Seal

Do not use brass tools,

they chip easily and

contaminate the

assembly process.


Hub retaining devices such as adjustment nuts

and locking devices should be properly set.

Fill the hub cavity with

recommended lubricant,

before axle installation.

Some hub assemblies are

equipped with see through

sight glass, for lubrication oil

level identification.


RimStud

ClampSpacer

On a dual wheel

assembly, ensure

spacer is of the

correct width for the

application.

On flange style wheel nuts, use

two drops of oil between the

flange and the hex..Oil


Typical wheel mounting

arrangement.

Single (front)

Dual (rear)

Nut Assembly

Flange

Nut

Assembly

Flange


1

25

43

1

2

3 4

5

6

1

2

3

4

56

7

8

9

10


Typical Wheel Tightening Patterns

Torque in three steps, 1/3, 2/3, and full torque,

according to manufacture’s torque specification..

Recheck torqued wheel nuts after 100 – 150 km.

Objective Five

Explain wheel balancing.

Wheel Balancing

Wheel balancing is required to maximize tire

life and to eliminate unnecessary vibrations..

Two main types of wheel balance problems

can exist..

Static Unbalance..

Wheel balancing is accomplished by using a computerized machine..

Dynamic Unbalance..

1.

2.

Few shops have hand type balancers.

Is a heavy spot in the center

of the tire which causes the

wheel to bounce, tramp or

hop..

Static unbalance may cause

localized tire tread wear,

shock absorber failure, poor

braking and steering,

because of loss of tire to

road contact.

Static Balance Problems

Bounce:

Heavy

Spot

Centreline of

Spindle

Dynamic Balance Problems

Is a heavy spot off center of

the tread, which causes a

shimmy or wiggle.

Dynamic unbalance may

cause tire wear (scuffing),

steering tie rod component

failure, as well as steering

problems.

Heavy

Spot

Shimmy:

Centreline of

Spindle

Check Wheel

Radial

Runout

Check Wheel Lateral

Runout

Check Total

Radial Runout

Check

Total Lateral Runout

Runout

Using a roller tip dial indicator, check

for total radial and lateral runout.

Radial Runout Lateral Runout

Cone Type Static Wheel Balancer

Balancer

Cone

Side View

(exaggerated) Top View

Light Side

(bubble not centered)

Tire Disc

Wheel Centre

Static Tire Balancing

At 180° opposite the heavy spot, place one half of

the required weight on each side of the rim,

Static Tire Balancing

Add Balance Weights Here

Heavy Spot

Corrective Weights:

Dynamic Tire Balancing

Can be done on or off the vehicle depending

on type of wheel balancer device used.

Cleanliness of the wheel and tire assembly is

critical for accurate balancing.

If balancing larger, lug type tire assemblies,

balance one side first, then the other side.

May be more accurate and less time

consuming.

Dynamic Tire Balancing

Corrective Weights:

Add Balance Weights Here

Heavy Spot

Always recheck tire balance after adding

recommended balance weight.

Objective Six

Diagnose wheel and tire faults.

Rear axle housing out of alignment can

cause tire scuffing and pulling to one side.

Introduction

Front

Axle

Rear

Axle

Leading End

Trailing End

Tire damage is most often caused by human

error, such as overloading, excessive speeds

and operating off-road..

Tire Damage

Tire damage may also be caused by:

Incorrect alignment settings..

Road hazards (rocks, nails, pot holes, etc).

Suspension damage..

Improper matching of tires..

ℴ

ℴ

ℴ

ℴ

Tire Damage

Tire damage may also be caused by:

Under-inflation Over-inflation

Feathered Edge

Tire Damage

A worn tie rod generally causes a feathered

edge. (Affects Toe)

Tire Damage

Punctures can affect tires

differently depending on

their construction design.

Sizing tires correctly on

each axle, ensures even

loading of the individual

tires.

Damaged

Bias Ply

Damaged

Radial

Wheel / Rim Damage

Flat spot on a wheel caused by

heavy loads and impacts, which reduces the air

retaining ability of the wheel or rim.

Chording –

THE

END

Wheels, Tires & Hubs

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Transcript of Wheels, Tires & Hubs