Screw Joints - ABB IRB 6640 Product Manual

7.4. Screw joints

General
This section details how to tighten the various types of screw joints on the robot.
The instructions and torque values are valid for screw joints comprised of metallic materials
and do not apply to soft or brittle materials.
UNBRAKO screws
UNBRAKO is a special type of screw recommended by ABB for certain screw joints. It
features special surface treatment (Gleitmo as described below) and is extremely resistant to
fatigue.
Whenever used, this is specified in the instructions, and in such cases, no other type of
replacement screw is allowed. Using other types of screws will void any warranty and may
potentially cause serious damage or injury.
Gleitmo treated screws
Gleitmo is a special surface treatment to reduce the friction when tightening the screw joint.
Screws treated with Gleitmo may be reused 3-4 times before the coating disappears. After this
the screw must be discarded and replaced with a new one.
When handling screws treated with Gleitmo, protective gloves of nitrile rubber type should
be used.
Screws lubricated in other ways
Screws lubricated with Molycote 1000 should only be used when specified in the repair,
maintenance or installation procedure descriptions.
In such cases, proceed as follows:
Lubricant
Molycote 1000 (molybdenum disulphide grease)
3HAC026876-001 Revision: F
1. Apply lubricant to the screw thread.
2. Apply lubricant between the plain washer and screw head.
3. Screw dimensions of M8 or larger must be tightened with a torque wrench. Screw
dimensions of M6 or smaller may be tightened without a torque wrenchif this is done
by trained and qualified personnel..
7 Reference information
7.4. Screw joints
Art. no.
11712016-618
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