jcb 540-170, Service Manual

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Section 1-4 - General Information
Torque Settings
Zinc Plated Fasteners and Dacromet Fasteners
1-4-2 1-4-2
9803/3750-05 (1-05-00)
Zinc Plated Fasteners and Dacromet Fasteners
T11-002
Introduction
Some external fasteners on JCB machines are
manufactured using an improved type of corrosion
resistant finish. This type of finish is called Dacromet and
replaces the original Zinc and Yellow Plating used on
earlier machines.
The two types of fasteners can be readily identified by
colour and part number suffix.
K
Table 1. Fastener Types
(
T
1-4-2) .
Table 1. Fastener Types
Note: As the Dacromet fasteners have a lower torque
setting than the Zinc and Yellow fasteners, the torque
figures used must be relevant to the type of fastener.
Note: A Dacromet bolt should not be used in conjunction
with a Zinc or Yellow plated nut, as this could change the
torque characteristics of the torque setting further. For the
same reason, a Dacromet nut should not be used with a
Zinc or Yellow plated bolt.
Note: All bolts used on JCB machines are high tensile and
must not be replaced by bolts of a lesser tensile
specification.
Note: Dacromet bolts, due to their high corrosion
resistance are used in areas where rust could occur.
Dacromet bolts are only used for external applications.
They are not used in applications such as gearbox or
engine joint seams or internal applications.
Bolts and Screws
Use the following torque setting tables only where no
torque setting is specified in the text.
Note: Dacromet fasteners are lubricated as part of the
plating process, do not lubricate.
Torque settings are given for the following conditions:
Condition 1
– Un-lubricated fasteners
– Zinc fasteners
– Yellow plated fasteners
Condition 2
– Zinc flake (Dacromet) fasteners
– Lubricated zinc and yellow plated fasteners
– Where there is a natural lubrication. For example,
cast iron components
Verbus Ripp Bolts
Fig 1.
Torque settings for these bolts are determined by the
application. Refer to the relevant procedure for the
required settings.
Fastener
Type Colour Part No. Suffix
Zinc and
Yellow Golden finish 'Z' (e.g. 1315/3712Z)
Dacromet Mottled silver finish 'D' (e.g. 1315/3712D)
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