Yale 524150797 Guide

Maintenance
METRIC AND INCH
(SAE) FASTENERS
PART NO. 524150797 8000 YRM 0231

SAFETY PRECAUTIONS
MAINTENANCE AND REPAIR
• When lifting parts or assemblies, make sure all slings, chains, or cables are correctly fastened, and that the
load being lifted is balanced. Make sure the crane, cables, and chains have the capacity to support the
weight of the load.
• Do not lift heavy parts by hand, use a lifting mechanism.
• Wear safety glasses.
• DISCONNECT THE BATTERY CONNECTOR before doing any maintenance or repair on electric lift trucks.
Disconnect the battery ground cable on internal combustion lift trucks.
• Always use correct blocks to prevent the unit from rolling or falling. See HOW TO PUT THE LIFT TRUCK
ON BLOCKS in the Operating Manual or the Periodic Maintenance section.
• Keep the unit clean and the working area clean and orderly.
• Use the correct tools for the job.
• Keep the tools clean and in good condition.
• Always use APPROVED parts when making repairs. Replacement parts must meet or exceed the
specifications of the original equipment manufacturer.
• Make sure all nuts, bolts, snap rings, and other fastening devices are removed before using force to
remove parts.
• Always fasten a DO NOT OPERATE tag to the controls of the unit when making repairs, or if the unit needs
repairs.
• Be sure to follow the WARNING and CAUTION notes in the instructions.
• Gasoline, Liquid Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Diesel fuel are flammable.
Be sure to follow the necessary safety precautions when handling these fuels and when working on these
fuel systems.
• Batteries generate flammable gas when they are being charged. Keep fire and sparks away from the area.
Make sure the area is well ventilated.
NOTE: The following symbols and words indicate safety information in this man-
ual:
WARNING
Indicates a hazardous situation which, if not avoided, could result in death
or serious injury.
CAUTION
Indicates a hazardous situation which, if not avoided, could result in minor
or moderate injury and property damage.
On the lift truck, the WARNING symbol and word are on orange back-
ground. The CAUTION symbol and word are on yellow background.

©2018 Yale Materials Handling Corp.
TABLE OF CONTENTS
General ..................................................................................................................................................................... 1
Threaded Fasteners ..............................................................................................................................................1
Nomenclature, Threads ........................................................................................................................................ 1
Strength Identification ........................................................................................................................................... 2
Cotter (Split) Pins ..................................................................................................................................................3
Fastener Torque Tables ........................................................................................................................................ 8
Conversion Table ................................................................................................................................................ 10
This section is for the following models:
Table of Contents
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General
THREADED FASTENERS
Threaded fasteners, like bolts, nuts, capscrews, and
studs, are made to specifications that describe the
mechanical strength and hardness of the fastener. A
fastener used in a design application is selected
according to its specifications. Yale® Company buys
parts from many countries. Parts that are purchased
must be to Yale® Company standards. There are
several standards used by these countries in the
manufacture of threaded fasteners. Many of these
fasteners are similar, but cannot be used as a direct
replacement. To make sure that you have the correct
fastener, order fasteners and parts through the Yale®
Parts Depot.
Service persons must use replacement fasteners that
have the same specifications. Fasteners made to each
specification have identification marks for that
specification. This specification is commonly called
"Grade" for SAE standards and "property class" for
metric standards. This section describes the
identification of some common fasteners.
The metric system used by Yale® Company is
described as SI (Le Systeme d'Unites or the
International System of units, also called SI in all
languages). The SI System of measurement is
described in ISO Standard 1000, 1973. A conversion
table of common measurements is shown in Table 7.
NOMENCLATURE, THREADS
The thread design is specified by a series of numbers
and letters for inch and metric fasteners. See Figure 1.
The diameter of the shank of the fastener is shown
first in the series [M12 = 12 mm, M20 = 20 mm (1/2 =
1/2 in., 3/4 = 3/4 in.)].
The number of threads per inch is normally not shown
for inch nomenclature and only the UNC (Unified
National Coarse) or UNF (Unified National Fine) is
shown. This number of threads per inch is not shown
because a UNC or UNF fastener has a standard
number of threads per inch for a specific diameter.
Metric fasteners show the number of threads per
millimeter.
The length of the shank is often indicated as part of
the description of a fastener. This length is shown in
inches for inch fasteners and in millimeters for metric
fasteners.
A capscrew will have the following description:
Metric Inch
M12 × 1.75 × 50 1/2 × 13 UNC × 1-1/2
A B C A B C D
A = Thread Size A = Shank Diameter
B = Pitch B = Number of Threads Per
Unit of Length
C = Length C = type of Thread
D = Shank Length
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Figure 1. Thread Design
STRENGTH IDENTIFICATION
CAUTION
When fasteners must be replaced, the new
fasteners must be of the same strength or greater
than the original fasteners. The new fasteners
must also be the correct size.
NOTE: Identification marks are according to bolt
strength. The higher the number or the increase in the
number of marks indicates increased bolt strength.
The most common property classes for metric
fasteners are 8.8 and 10.9. The property class is
marked with a number on the head of the capscrew or
on a nut. Property classes less than 8.8 are often not
marked. Grades for inch bolts go from 2 to 8. Grade 2
fasteners normally do not have any marks. The
following tables show the marks that identify the
grades and property classes for different fasteners.
General 8000 YRM 0231
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COTTER (SPLIT) PINS
Cotter (split) pins are used in many applications on
your forklift. They are typically used to retain parts
such as pins and nuts. Cotter (split) pins are typically
not used as load-bearing members. Service personnel
must use new cotter (split) pins. Do not reuse a cotter
(split) pin. Replacement cotter (split) pin must be of the
correct size. See Table 8.
The legs of a cotter (split) pin are bent for the following
reasons:
•To retain the cotter (split) pin in the part
•To provide clearance between the cotter pin
legs and other parts or members. One or both
cotter (split) pin legs must be bent to provide a
minimum 90° angle between the legs. See
Figure 2.
Figure 2. Minimum Angle Between Cotter Pin Legs
Unless otherwise specified, the legs of chain anchor
cotter (split) pins are to be bent against the pin. See
Figure 3.
1. COTTER PIN
Figure 3. Cotter (Split) Pins Used On Mast Chain
Anchors
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Table 1. Bolts and Screws
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Table 2. Studs and Nuts
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Table 3. Torque Nuts
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