Mts Series 647 Hydraulic Wedge Grips Manuel d'utilisateur télécharger pdf (Page 79)

DescriptionItem

Hydraulic Grip Supply3

Determine Gripping Pressure

About Grip Pressure Determination

The output pressure of the hydraulic grip supply determines the gripping force applied to the specimen by

the wedges. The optimum gripping force is great enough to securely grip the specimen, yet low enough to

minimize specimen deformation or prevent specimen slippage during the test.

Warning:

Improper grip pressure can damage the grips.

Insufficient grip pressure can result in specimen slippage or wedge movement which can damage

the grips. Using a grip pressure that exceeds the pressure rating of the grip can result in damage

to the grips.

The minimum pressure level, calculated in the following procedures, ensures that the wedges

will be properly seated in the wedge chamber to prevent any movement of the wedges within the

chamber when a full axial or load is applied to the specimen.

Definition of terms

This section defines the parameters used in the gripping pressure formulas. The figure “Gripping Principles”

illustrates some of the parameters.

A = Area of the grip piston (cm

or in

)

AModel

2.54 in

16.38 cm

647.02

10.30 in

66.45 cm

647.10

7.84 in

50.58 cm

647.25

12.51 in

80.75 cm

647.50

26.95 in

173.96 cm

647.100

64.6 in

416.77 cm

647.250

Series 647 Hydraulic Wedge Grips Reference Manual 79

Operation

1 2 ... 74 75 76 77 78 79 80 81 82 83 84 ... 95 96

Pas de commentaire

Mts Series 647 Hydraulic Wedge Grips Manuel d'utilisateur Page 79