China Factory for Ceramic Straight Edge - Precision Granite Tri Square Ruler – ZHONGHUI

All Granite Rulers are tested in a temperature (20°C) and humidity controlled environment.

All ZHHIMG® plates are supplied with a Test Report, in which error map and installation instructions are reported.

Calibration Certificate available on request*.

The chart shows standard sizes, weights, article codes and the absolute flatness tolerances (in micrometers).

ZHHIMG® can supply plates with different sizes according to customer needs and drawings, with holes, threaded inserts, guide or clamping T-slots, clearing grooves and with rubber feet (for the smaller sizes).

Granite is a type of igneous rock quarried for its extreme strength, density, durability, and resistance to corrosion. Ultra Precision Manufacturing Department at ZhongHui Intelligent Manufacturing Group confidently works with granite components engineered in shapes, angles, and curves of all variations on a regular basis—with excellent outcomes.

Through our state of the art processing, cut surfaces can be exceptionally flat. These qualities make granite the ideal material to create custom-size and custom-design machine bases and metrology components.

Our Superior Black Granite has low water absorption rates, minimizing the possibility of your precision gages rusting while setting on the plates.

When your application calls for a plate with custom shapes, threaded inserts, slots or other machining. This natural material offers superior stiffness, excellent vibration dampening, and improved machinability.

Due to its unique properties, black granite in recent years, has been used extensively in the field of measuring  instruments, both for traditional ones (surface plates, parallels, set squares, etc…), as well as modern ones:  CMM machines, physic-chemical process machine tools.

Due to its unique properties, black granite in recent years, has been used extensively in the field of measuring  instruments, both for traditional ones (surface plates, parallels, set squares, etc…), as well as modern ones:  CMM machines, physic-chemical process machine tools.

Suitably lapped black granite surfaces are not only extremely precise but also ideal for use in conjunction with air bearings.

The  reason  of  the  choice  of  black  granite  in  manufacturing  of  precision units are the following:

DIMENSIONAL STABILITY: black  granite  is  a  natural  aged material   formed   over   millions of   years   and    therefore   displays  great  internal  stability

THERMAL STABILITY: the  linear  expansion  is  much  lower  than  the  steel  or  cast  iron ones

HARDNESS: comparable to good-quality tempered steel

WEAR RESISTANCE:  instruments last longer

ACCURACY: the flatness of the surfaces is better than the one obtained with traditional materials

RESISTANCE TO ACIDS, NON-MAGNETIC ELECTRICAL INSULATION RESISTANCE TO OXIDATION: no corrosion, no maintenance

COST: working the granite with state-of-the-art technology prices are lower

OVERHAUL: Eventual servicing can be carried out quickly and cheaply

1. Documents together with products: Inspection reports + Calibration reports(measuring devices) + Quality Certificate + Invoice + Packing List + Contract + Bill of Lading(or AWB).

2. Special Export Plywood Case: Export fumigation-free wooden box.

3. Delivery:

1. We will offer technical supports for assembly, adjustment, maintain.

2. Offering the manufacturing &inspection videos from selecting material to delivery, and customers can control and know every detail at anytime anywhere.