Instron 300DX, Руководство по эксплуатации

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Chapter 4: Maintenance
72 M47-17027-EN
Grip assemblies - G1-style and G7-style crossheads
Warning
The grip assemblies must receive regular care to prevent damage to grip pockets and grip components.
In general, the frequency guidelines stated in the
“Preventative maintenance schedule” on page 61
will give you a good indication of when and how to care for your grips. However, if your system is used in a
very dirty environment or to test specimens that create debris at fracture, then those frequencies may
need increased.
Clean external surfaces and check operation of grip assemblies
The external surfaces of the grip assemblies should be cleaned of dirt and debris at the frequency stated
in the
“Preventative maintenance schedule” on page 61 . The external surfaces include the exposed
portions of the grip pockets and the face of the grip jaws. This cleaning is particularly important for the
lower grip body because it will tend to collect more dirt and debris.
Open and close the grip jaws as necessary to make it easier to reach all surfaces. For frames with G1-
style crossheads (closed pockets), it may be easier to remove the grip jaws from the crosshead. Various
methods can be used to remove the dirt and debris: a rag or cloth, a brush (medium sized, with medium-
stiff bristles is recommended), or a vacuum.
For specimens that create a lot of debris at fracture (such as rebar), it will probably be necessary to
increase the cleaning frequency to every few tests instead of only once a day. Also, it can be very helpful
to use some type of protective cover around the specimen and over the grip pocket to reduce the amount
of debris that falls into the grip pocket. This cover can be made of paper or cardboard with a specimen-
sized hole cut out in the middle. For a really simple cover, use a paper or Styrofoam plate. Just make sure
that the cover does not interfere with testing or operation of the grip assemblies.
Once the grip assemblies have been cleaned, check the operation of the grip assemblies with a set of grip
jaws installed. Open and close the grip jaws several times and check for binding and abnormal noise.
The grip jaws should move smoothly. For frames with G1-style crossheads, be sure that the grip jaws stay
aligned with each other as they are opened and closed. If they do not, this indicates a damaged pinion
that probably needs to be replaced. Refer to
“Inspect and replace the pinion - G1-style crossheads”
on page 79 .
Lubricate the grip assemblies
The grip assemblies must be properly and sufficiently lubricated to operate properly. Grip components
should be lubricated at the frequency stated in the
“Preventative maintenance schedule” on page 61
- be sure to read Footnote 1 in this section. Use of Molykote type GN metal paste (high pressure
lubricant) is necessary for proper operation of the grips. Instron recommends only this brand and type of
high pressure lubricant. Use of any other lubricant risks damage to the grip components. This damage
would not be covered under warranty. A small amount of Molykote type GN metal paste is supplied with
the frame, additional quantities can be purchased from Instron, contact your local Instron Services
department as directed on page
20 . Lubrication procedures are different depending on whether the
Always wear appropriate personal protective equipment when preparing, operating and
maintaining this equipment. Personal protective equipment should include, but is not
limited to, eye protection and head protection. Other types of personal protective
equipment may also be needed. You must perform your own risk assessment and take
appropriate measures to protect yourself from harm.