Section 1: Principle of Liquid Expansion Clamping Device
The difference from the standard liquid expansion fixture lies in the use of static pressure expansion technology. After the fixture is pressurized, the hydraulic medium generates a high pressure under the action of the pressure mechanism, forcing the deforming element to uniformly deform elastically in all directions within the clamping range of 360°, thereby achieving tightness on the locating hole/axis of the workpiece.
Section 2: Features of Liquid Expansion Clamps
1. The fixture is filled with a liquid medium internally.
2. The working surface of the fixture is elastic deformable.
3. The workpiece is held in a circular clamp with even pressure and without deformation.
4. High clamping force, up to 100MPa
5. Small workpiece deformation, high machining accuracy; fixture dynamic accuracy less than 0.003MM.
6. Fast workpiece clamping and dismounting, high work efficiency.
7. Customized according to equipment and workpieces, with strong adaptability.
8. The expansion is 0.3% of the clamping diameter.
9. Utilizing taper springs, spline springs, and other accessories, various size and specification workpieces can be processed.
10. Achieves quick changeover for workpieces and fixtures
Section 3: Structure and Types of Liquid Expansion Clamps


Grinding Application





Section 4: Technical Parameters of Liquid Expansion Clamps
1. Applicable Range
The maximum allowable expansion of the liquid-filled fixture does not exceed 3% of the clamping diameter; generally, good clamping accuracy and service life can be achieved when the dimension tolerance of the clamped workpiece section is H7 or higher.

2. Pressure Control
Manual hydraulic expansion clamping devices are strongly recommended to use a torque wrench and apply pressure according to the recommended torque values; hydraulic expansion clamping devices for machine tools with automatic pressure should also be pressurized according to the recommended machine thrust, pull force, or hydraulic cylinder oil pressure.
3. Precision Testing
Jig precision shall be checked against standard parts, and the accuracy should comply with the technical agreements between both parties.
4. Pressure Testing
The fixture failed to clamp the standard parts within the recommended pressure range, indicating a failure in the liquid swelling fixture's clamping. Please contact the company's technician.
Section 5: Precautions for Using Liquid Expansion Clamps
① Daily attention should be given to the liquid expansion fixture, ensuring that the expansion area is not left to expand empty without workpieces or standard parts being held.
②Apply anti-rust oil evenly and regularly; note that the anti-rust period is three years. Especially, do not forget the anti-rust treatment before and after use.
Upon completion or during periodic use, ensure comprehensive dust protection to prevent any impact on subsequent use.
④Recommended to pack the liquid expansion fitting in wooden boxes and store it in a dry, spacious area.































