Why the Segment of Diamond Blades Can Break Off

Hanjiang Wang — Mon, 13 Jun 2011 02:52:15 +0000

A common problem diamond blade users may encounter is that one (or more) segment break off the diamond blade. This problem is often known as segment loss, which not only means the damage of the diamond blade, but may cause serious security issues because of the segment flying out.

A laser welded diamond blade with a segment lost

The reasons of segment loss (break) of diamond blades are diverse. If diamond saw blades has no problem in quality and the segments are connected to the blade’s steel core firmly, the following causes may lead to segment loss:

1. Wet diamond blades are used with inadequate water or even dry

During the cutting process, if there is no adequate water flowing on both sides of the diamond blade and in the cut, excessive heat may be generated and there may be some abrasive slurry remaining in the cut.

If the wet diamond blade is laser welded, the abrasive slurry can wear away the blade’s steel core just beneath the segment. This problem is often called undercutting. Serious undercutting can cause the segment to break from the steel core.

If the wet diamond blade is silver brazed, the excessive heat can cause the silver solder which connects the segments to the steel core to be melted, and then the segments may break off.

So adequate water is critical to the wet cutting job, for it can avoid overheating of the diamond blade and can wash out the abrasive slurry. Overheating can also make the diamonds on the segments become blunt. If a wet diamond blade is used without any water (dry), it may take just a few seconds for the blade to be damaged.

2. Dry diamond blades are not used properly

Laser welded diamond blades can be designed to cut some materials without water. However, if dry laser welded diamond blades are used dry arbitrarily, the segment may still break off the diamond blade.

As dry cutting utilizes the air as its coolant, dry diamond blades should be used in the intermittent and shallow sawing mode to allow the air to flow around the blades to dissipate the heat. You can read our how to use diamond blades in dry cutting article for more information. If a dry diamond blade is used in continuous or deep cutting, the blade may be overheated and may lose its segments.

Not all materials can be cut dry. Some very hard materials, e.g., concrete with strong reinforcement, should still be cut with water. Wet cutting can improve cutting efficiency, control dust, and extend the diamond blade’s life.

3. Problems related with the saw machine

If the saw machine’s blade shaft or shaft bearings are worn, the diamond blade may jump up and down in the cutting process. This can lead to segment loss. Replacing the shaft or shaft bearings can resolve the problem.

Some other reasons can also make the diamond blade flutter and then cause segment loss. These reasons include: the diamond blade is mounted on the shaft incorrectly; the nuts or bolts which hold the flange and blade shaft together are not wrenched tight; there is dirt, sand or other materials between the blade steel core and the flange.

4. The material being cut slips and jams the diamond blade

This situation is typically seen in masonry or tile sawing applications and may cause segment loss. To avoid this, the operator should make sure that the material is seated securely on the saw machine, and that he holds the material firmly through his entire cutting process.

Cutting Manners of Diamond Tools – From the Cooling View

Hanjiang Wang — Sun, 12 Jul 2009 10:36:27 +0000

From the cooling point of view, diamond tools can be used in 3 cutting manners: dry cutting, wet cutting and immersion cutting. The 3 manners have their own characteristics and application ranges.

1) Dry Cutting: The equipment used in dry cutting is not very expensive, its cutting speed, however, is fairly fast. When the suitable or ideal coolant is hard to find, dry cutting is often adopted. Sometimes, when some difficult conditions are met, dry cutting also has to be used. Dry cutting is economical.

2) Wet Cutting: When wet cutting is used, a cooling circulatory system will be mounted on the machine, which can dissipate the heat generated in cutting. Wet cutting can get precise and good-looking cutting surface, and can avoid burning the workpiece, but its cutting efficiency is apparently lower than dry cutting, by about a half.

Normally, the coolant used in wet cutting is water mixed with some soluble oil and/or some chemical preservatives. A large amount of coolant should be poured on the workpiece to avoid uneven wear of the diamond tool. This uneven wear can influence the precision of the cutting surface.