Instron 300DX, Руководство по эксплуатации

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Mount fixtures
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Filler plate guidelines (G1-style crossheads only)
Filler plates are an important part of the specimen gripping assembly. They assure the alignment of the
specimen with the centerline of the grip pocket as well as axial alignment of the specimen. They also
assure that the grip jaws do not extend beyond the crosshead (into the test space) when the specimen is
gripped. Tests that are performed with the grip jaws extended beyond the crosshead will cause serious
damage to the grip jaws and lead to grip pocket deformation. Grip jaw damage and grip pocket
deformation caused by this type of use is NOT covered under warranty, see
“Specimen guidelines” on
page 43 for more information.
When installing filler plates, it is imperative to remember the following:
•
Insert the filler plates into the grip pocket from the top of the crosshead so that they sit between the
grip pocket and the sloped side of the grip jaw. The shoulders of the filler plate rest on the top of the
crosshead and prevent the filler plate from falling through the crosshead.
•
Install filler plates of the same total thickness behind each grip jaw. This assures alignment of the
specimen with the centerline of the pocket as well as axial alignment of the specimen between the
tension crosshead and adjustable crosshead.
•
Be sure enough filler plates are installed so that the narrow end of the grip jaws does not protrude
beyond the crosshead when the specimen is gripped. Failure to keep the narrow end of the grip jaws
inside the pocket during a test will cause serious damage to the grip jaws and lead to grip pocket
deformation.
•
Use enough filler plates so that at least the minimum gripping requirements are met; see “Specimen
guidelines” on page 43 . When the minimum gripping requirements are NOT met, the grip jaw will
tip and cause damage to the grip pocket and other grip components. Often the specimen may slip
and cause damage to the face of the grip jaws.
Caution
Tests that are performed with the grip jaws extended beyond the crosshead will cause
serious damage to the grip jaws and lead to grip pocket deformation. Use as many filler
plates as required so that the narrow end of the grip jaws does not protrude beyond the
crosshead when the specimen is gripped.
Filler plates are used for G1-style crossheads only.
This does not apply to grip jaws that are made to test non-uniform specimens, such as angle grip jaws. In
these cases, it is typically necessary to use filler plates of different thickness for each grip jaw so that
proper specimen alignment can be achieved. The goal is to achieve alignment of the specimen with the
centerline of the pocket as well as axial alignment of the specimen between the tension crosshead and
adjustable crosshead.