Forklift Fundamental

Forklift Fundamental

February 2008 Overseas Sales & Marketing Forklifts Business Group

CONTENTS

• What are forklifts • Terminology • Load Capacity

• Mast Types

What are Forklifts Classification by Industrial Truck Association (ITA, USA) Class 1 : Counter-balanced Electric Riding type Forklift

• Conventional Forklifts

Class 2 : Riding type Electric Warehouse Equipment

- Class 1 : C/B Electric

Class 3 : Pedestrian type Electric Warehouse Equipment

- Class 5 : C/B I.C. Pneumatic type

Class 4 : Counter-balanced Internal-combustion Cushion Tire type Forklift Class 5 : Counter-balanced Internal-combustion Pneumatic Tire type Forklift Class 6 : Tractors

- Class 4 : C/B I.C. Cushion type

• Warehouse Equipment - Class 2 : WH - Riding type - Class 3 : WH - Pedestrian type • Class 1 - 5 are regarded as forklifts and others ( 6 – 8) are not.

Class 7 : Rough Terrain Forklift Class 8 : Manual and Semi-powered Pallet truck

What are Forklifts C/B Forklifts and Reach Truck – Doosan Range Class 1 C/B Electric : Prefix “B”

Class 4 C/B I.C. Cushion type : Prefix “GC” Class 5 C/B I.C. Pneumatic type : Prefix “D or G”

Class 2 WH, Riding type : Prefix “BR”

Classification by number of Wheels • 3-wheels ... Surffix “T” • 4-wheels ... Surffix “S” or “X”

Classification by fuel type • Diesel ... Prefix “D” • LPG ... Prefix “G” or “GC” • Gasoline ... Prefix “G” or “GC”

Classification by riding type • Sitting type … Suffix “J” or “JW” • Standing type … Suffix “S”

What are Forklifts Warehouse Equipments (WH)

Class 2 WH Riding type Ride Pallet Truck

Reach Truck High Lift Stacker

High Level Order Picker

Class 3 WH Pedestrian type

Power Pallet Truck Low Lift Pallet Truck

Low Lift Warkie High Lift Stacker Horizontal Pedestrian Order Picker Stacker

Pedestrian High Level Order Picker

What are Forklifts Major Components Front Combination Lights

Front Working Lights

Overhead guard MAST Seat with Hip Restraint Load Backrest Counter-weight Carriage Steer / Rear Tires

Forks

Drive / Front Tires

Tilt Cylinders

What are Forklifts Major Components Steering Wheel & Knob

Strobe Light

Back-Up Alarm

Rear Working Light Parking Brake Rear Combination Lights

Control Levers

CONTENTS

• What are forklifts • Terminology • Load Capacity

• Mast Types

Terminology – Dimensions of Mast

• MFH : Maximum Fork Height … no. 9 Height from ground to upper face of forks, at upright / vertical position of mast with rated load weight It is the required height for stored height of load.

• OAL : Over All Height … no. 17 & 19 (Mast Fully Lowered Height) Height from ground to upper end of mast at fully lowered fork position at upright / vertical position of mast If overhead guard is higher than this, OAL is height to the upper end of overhead guard

Terminology - Dimensions of Mast • FFH : Full Free Lift Height … no. 10 Height from ground to to upper face of forks without extending the mast (or, height to the position of forks without change of mast’s OAL), without load In case of FF and FFT mast, FFH is different for cases of “with Load backrest” and “without”, due to the height of Load backrest. It is useful for operation with low ceiling building, container or entrance door.

• Maximum Mast Extended Height … no. 18 Over all height from ground to height upper end of equipment (carriage, load backrest or forks) when fork is fully lifted or when mast is fully extended, at upright / vertical position of mast This height is different for cases of “with Load backrest” and “without”, due to the height of Load backrest.

Terminology - Dimensions of Mast Forward Tilt Angle

Backward Tilt Angle

• TILT ANGLE … no. 14 a) FORWARD TILT ANGLE Angle degree of tilting the mast to maximum forward position, from vertical position of mast. b) BACKWARD TILT ANGLE Angle degree of tilting the mast to maximum backward position, from vertical position of mast As this angle is critical for truck’s stability and rated lifting capacity at high fork position, the degree could be reduced. • LOAD MOMENT CONSTANT … no. 22 Distance between center of front tires and fork’s face at vertical position of mast It is making influence to truck’s length and truck’s rated capacity.

Terminology - Dimensions of Vehicle • OVER ALL LENGTH Length between rear-end and front-end of forks Points to be considered : - Minimum turning radius - Minimum intersection (90 degrees) aisle width LENGTH TO FORK FACE … no. 15 Length between rear-end of vehicle and fork’s face

WHEEL BASE … no. 38 Distance between center of front wheel and center of rear wheel While wheel base is increasing, vehicle’s front-read stability and rated capacity are getting better, but, working condition is getting worse due to bigger turning radius.

Terminology - Dimensions of Vehicle • TURNING RADIUS … no. 21 Minimum radius of truck’s outside trace of turning at minimum travel speed , by maximum steering angle, with un-load

• AISLE 90 DEGREE STACKING … no. 23 (= RIGHT ANGLE STACKING AISLE) Minimum aisle width for forklift’s turning by 90 degrees angle for staking load Points to be considered : - Aisle width between shelves at both sides Caution : It is variable depending on size of load Calculation of real Aisle Width : Turning Radius (Minimum) + LMC (Load Moment Constant) + Length of Load / Forks + Clearance

Terminology - Dimensions of Vehicle • OVER ALL WIDTH … no. 16 Width between end of both sides as Drive axle, Tires, Fenders, Forks, Carriages … Points to be considered : - Width of entrance, aisle and load - Turning radius of forklift

• WHEEL TREAD Width between centers of left and right wheels While wheel tread is increasing, vehicle’s left-right stability and rated capacity are getting better but, working condition is getting worse due to bigger turning radius and in narrow aisle.

Terminology - Dimensions of Vehicle • GROUND UNDERCLEARANCE The height from ground to lowest position of vehicle, such as lowest end of outer mast, drive axle housing or frame Considering point : rough surface and obstacles on ground

• TOTAL SERVICE WEIGHT (UN-LOADED) … no. 32 Total weight of vehicle without load and operator Considering point : Transportation and lifting the truck for moving

Terminology - Performance • GRADEABILITY … no. 30

H

L

Tangent percent (tan θ%) of a slope which forklift’s ability to ascend with rated load The gradeability varies by surface condition. If the surface is clear or wet, it would be reduced. So, actual gradeability would be different from the data on specification sheet. Measuring unit of it is different from manufacturer to manufacturer. Formula of Gradeability = Height of Slope (H) / Length of Slope (L) X 100% • DRAWBAR PULL … no. 28 Towing force exerted in the direction of motion of forklift trucks coupling point The maximum force is determined upon the friction between the drive wheels and the supporting surface when the load is being moved at a rate of 1 MPH. This data is extremely important because the bigger\ the drawbar pull, the “stronger” the truck is.

Terminology - Performance • TRAVEL SPEED … no. 24 Truck’s maximum driving speed with loaded or unload when the accelerator pedal is to the floor and the engine is at wide open throttle and maximum RPM.

• LIFTING AND LOWERING SPEED … no. 25 & 26 Mast and/or forks’ speed of lifting and lowering speed with load or unload

The lowering speed is limited and controlled by a valve to prevent both vehicle instability and damage to the load which can result from sudden drops caused by the weight of the load.

Terminology - Performance • LOAD CENTER … no. 4 Distance from fork face to center of load If a load has for example a length of 1 meter, its load center is at 500 mm

Load Center (L/C)

Load Moment Constant (LMC)

Load center by lifting capacity : - 1.0 to 3.0 ton: 500mm as base - 3.5 to 5.0 ton: 600mm as base and 500mm as option - 5.5 and over : 600mm as base

• CENTER OF GRAVITY (C.G.) Each solid body has a certain weight and a Center of Gravity which is assumed to be located in the exact center i.e. at the equidistant center of all its sides. (in the case of a regularly shaped body.)

Terminology - Performance • RATED LOAD CAPACITY … no. 3 Maximum lifting weight of load at load center at vertical position of mast As there are various factors influencing to the capacity, those factors have to be reviewed to determine actual capacity. The load capacity of a forklift truck varies depending on the horizontal distance between the vertical surface of the forks and the center of gravity of the load. • LOAD CAPACITY CHART A forklift truck equipped with a load chart indicates this relationship between the distance and the load capacity. The X-axis shown on the load chart is called the load center and the Y-axis is the maximum load capacity.

CONTENTS

• What are forklifts • Terminology • Load Capacity

• Mast Types

Load Capacity CENTER OF GRAVITY (C.G.)

We may reasonably estimate that the center of gravity of the load agrees with its physical center, when the load has a uniform form

And that its position varies based on the load position If the load position changes, the location of the C.G. also does, accordingly

Imbalance happens and then, upset

if the weight of one of its sides is increased or separated

Such accident is more likely on unven grounds or ramps and when the mast is fully extended and inclined backwards with heavy loads.

Load Capacity What happens when lifting a load ? When the load rises the resulting center of gravity movers upwards following an intermediate vertical line between the centers of gravity of the lift truck and the load

The lift truck without load is a mass that has its own center of gravity

When a forklift takes a load, the centers of gravity moves to the wheel and the load are combined forming a resulting center of gravity

Load Capacity What happens when the mast tilts forwards ?

.... The resulting center of gravity moves up

The weight of the load, and the elasticity of the mast makes the situation still even more critical

Whenever one inclines the loaded mast towards ahead, it is necessary to be an extreme careful

The truck looses its balance !

Load Capacity What if the loaded mast is tilted backwards while highly extended ? Here again, we risk upset ! Once again, materials handling equipment is sure and stable. However, any manoeuvre with load and especially when the mast is extended requires some precautions. And of course, any brutal manoeuvre shoud be avoided.

Forkflifts lean on 4 points, 4-wheels But, as the back axis has a swing capacity so that the 4 wheels lean on the ground on unequal lands

in terms of lateral (right-left) stability, the forklifts leans on this triangle of stability

Load Capacity Once again, when a forklift takes a load, the resulting center of gravity moves ahead

...and that the resulting center of gravity also moves according to the tilt of the mast

And, for the same reason, when the mast tilts backwards.. The resulting center of gravity moves backwards

Load Capacity The lifting (load) capacity is always specified ”with load center “

Such a long load should be light in order to be handled safely

Here the capacity is even more reduced due to a very long load length

With such a distant load center, the lifting capacity is considerably reduced !

Load Capacity Each specification sheet includes a curve which illustrates the influence of the load center on the load capacity Model : D30S-5, G30E-5, G30P-5 Mast “A” : MFH 2030 – 4350 Mast “B” : MFH 4960

This truck has a nominal capacity of 3000 kg center at 500 mm. If the center of the load were located to 700 mm, the capacity would be approximately 2500 kg.

If the center of the load were located to 900 mm the capacity would be of about 2200 kg. And with the load center at 1200 mm the capacity would be reduced to less than 1800 kg.

Load Capacity MAST CAPACITY CALCULCATION by Load Center P : Basic (Nominal) rated capacity of Mast (KG) LMC: Distance from drive wheel center to fork shank front face (mm) LC : Truck rated load center (mm) W’ : Allowable capacity in special customer's load center (kg) LC’ : Special L.C of customer (mm) T : Fork Thickness (mm)

Capacity conversion from truck rated L.C. to customer's special L.C.

Load Capacity Mathematical calculation of the lifting capacity To calculate the capacity of a forklift if the center of gravity of the load located at 500 mm Basic (Nominal) Capacity .... = 2000 kg Distance to the load gravity center ------------------------------. = 500 mm Load Moment Constant (LMC) = 445 mm (Distance from drive wheel axis to the forks front face)

First, we will determine the nominal capacity of forklift through following calculation : Front moment of the forklift : 2000 x (500 + 445) = 1.890.000 kg/mm Distance from the front axis to frontal face of the forks ......... 445 mm Center of gravity of the load .............................................. 700 mm 1.890.000 445 + 700

= 1,650.6 kg

at 700mm L.C.

Load Capacity ATTACHMENT INSTALLED CAPACITY CALCULATION Wa : Attachment Weight (kg) LL : Attachment Load Lost (Attachment thickness - mm) CG : Attachment Center of Gravity (mm) LCa : Rated Load Center of Attachment (mm) Pa : Maximum Allowable Capacity of Attachment at Rated Load Center (kg) A : Longitudinal Length of Unit Load (mm) W : Unit Load Weight (kg) LMC: Distance from drive wheel center to fork shank front face (mm) LC : Truck rated Load Center (mm) T : Fork Thickness (mm) P : Basic (Nominal) rated capacity of Mast (Attachment uninstalled capacity-kg) Pc : Attachment installed capacity (kg)

Load Capacity ATTACHMENT INSTALLED CAPACITY CALCULATION 1) Select proper Attachment (Confirm related data from catalog etc) a) Check rated Load Center of Attachment and customer's actual working Load Center. If same, following calculation is unnecessary. Only need to compare rated capacity of Attachment and customer's working Load. b) If working L.C is longer than rated L.C of Attachment, make sure whether Attachment Capacity is larger by following formula.

2) Calculate capacity when attachment is installed 3) Compare Pc and W value. When Pc is larger than W, considered Truck and Mast will be possible. If smaller, select more large capacity truck and recalculate. 4) If working Load Center (working load x 0.5) is smaller than truck rated L.C, working load center shall be considered with truck rated Load Center.

Load Capacity USING LOAD CAPACITY TABLE (Excel File) Doosan is offering Rated Load Capacity Table by Excel File. 1)

In order to find the capacity, following points have to be known. - Truck Model - Attachment - Mast - Tilt Angle of Mast - Tire - Load Center required

2) Choose Type of Attachment - supplied from Doosan a) Models with capacity <= 5.5 ton - Capacity Without Sideshifter - Capacity With Hook-On type Side-shifter - Capacity With Integrated Side Shifter - Capacity Integrated Shifting type Fork-Positioner : Common use as capacity with Side-Shifter - Models with 3.5 – 5.5 ton With Fork-Positioner of Side-Shifter + Fork-Positioner : Use Capacity with “Shaft type” carriage b) Models with capacity 5.0 – 16.0 ton - Capacity Without Sideshifter - Capacity With Side-shifter and With Sideshifter + Fork-Positioner - Capacity With Fork-Positioner - D80/90S With Fork-Positioner : Common use as capacity Without Side-Shifter

Load Capacity USING LOAD CAPACITY TABLE (Excel File) Capacity at Load Center 900mm of : D25S-5 + Integrated Sideshifter + FFT 4730 mast + Tilt angle 6-8 degrees ? 1. Open excel file of the Model and Choose “Sheet” of Attachment

2. Find Mast, Tilt angle, Tire and Load Center 3. You can not miss the Capacity

CONTENTS

• What are forklifts • Terminology • Load Capacity

• Mast Types

MAST types Standard Mast (STD) 2-stage Low Free Lift Mast Duplex Mast

Full Free Lift Mast (FFL) 2-stage Full Free Lift Mast Duplex Mast

Full Free Triple Mast (FFT) 3-stage Full Free Lift Mast Triplex Mast

- Total visibility - Limited Free Lift (+/- 150mm). - It cannot work in areas wit h low height of warehouse or entrance.

- Fork’s free left without moving mast.

- Fork’s free left without moving mast.

- Suitable for waoring in a container of low warehouse of entrance.

- Application for high lifting height is necessary as well as for low height area

MAST types Standard Mast (STD) : 2-stage Mast / Duplex Mast

MAST types Full Free Lift Mast (FFL) : 2-stage Full Free Lift Mast

MAST types Full Free Triple Mast (FFT) : 3-stage Full Free Lift Mast / Triplex Mast

MAST types Quadruple Mast : Quad Mast / 4-Stage Mast

MAST types How to choose a Mast a) Check the entrance Door and choose OAL of mast

Height of Entrance Door Clearance has to be more than 100 mm.

OAL

MAST types How to choose a Mast b) Check MFH of mast and height of load and height to warehouse

Height of Warehouse & over

Height of Load

& over

Height of Load

& over

Max. Stacking Height

THANK YOU