Blow Bar Introduction

They are thick slabs of alloy
Its function is to fracture materials
There are metallurgical types of blow bars
There are a variety of factors that affect its wear
The impact crusher plays an important role in reducing the size of various materials needed in many applications. However, there is a specific part of the crusher responsible for the manual crushing of materials. 

They are thick slabs of alloy
The impact crusher blow bars are also known as hammers because of their primary function. Its blow bars are made into large and very thick slabs of alloy or other metal composites.
Each impact crusher has three to four sets of blow bars in the machine. They are inserted into its rotor where they strike the different kinds of material that need to be processed by the crusher. 
Among all the other parts of an impact crusher, its blow bars are the ones that wear down quickly. 

Its function is to fracture materials
In an impact crusher, the blow bars strike all materials that are fed into the machine. They act like a hammer and smash the various materials against the impact wall. This is what causes the materials to break into small particles. 
These blow bars are meant to crush materials like concrete, asphalt, and even natural stone into very small fragments.
The most common impact crusher is the horizontal shaft impact crusher. In this model, the blow bars are placed inside its rotor. To fracture the materials put inside the feed, the crusher must be turned on at high speeds. As the rotor continues to spin, the blow bars hit the materials put inside the chamber. 

There are metallurgical types of blow bars
Foundries make blow bars using different metallurgical compositions. Each type is meant to break down a different type of material

1.Martensite Ceramic Blow Bar
These are martensitic blow bars that have ceramic applied through the entire bar. Its two components, martensite & ceramic, give the blow bar different characteristics. 
This blow bar's alloy is made of martensite. This is responsible for providing it with high-impact resistance. On the hand, its ceramic coating helps in keeping wear and tear at bay since it can withstand abrasions. 
This blow bar is used for larger feeds of asphalt and natural stone primary crushing since it's known to be highly abrasive. 

2.High Chrome Blow Bar
When there are high levels of chrome in a blow bar, its ability to withstand abrasive feeds increases. That's why this is used in crushing both natural stone and asphalt. However, this blow bar is not able to protect itself from wear when recycled materials with metal contaminate the feed. 
The feed size must always be controlled with high chrome blow bars to avoid fractures. 

3.High Chrome with Ceramic Inlays Blow Bar
Just like Martensite Ceramic blow bars, High Chrome Blow Bars with Ceramic Inlays also have ceramic applied throughout its bar. This expands its wear resistance. This makes them effective and good for use when it comes to feeds with highly abrasive materials. 
High Chrome Blow Bars with Ceramic Inlays are usually used for secondary and tertiary crushing but should be avoided when feeds are too large.

4.Low Chrome Blow Bar
Low Chrome blow bars can perform well with feeds that contain concrete with steel and other highly contaminated materials. This type of blow bar is also able to accept larger feeds compared to high and medium chromes. 
It's commonly used with concrete and recycling applications.

5.Medium Chrome Blow Bar
Medium chrome bars have higher resistance to impact compared to high chrome bars. Because of that, it can accommodate larger feed sizes. However, these blow bars can also wear down quickly with highly abrasive materials. 
Avoid using this type of blow bar when procession reclaimed asphalt pavement. 

The Feed Size
To avoid the fast wear down of your hammers, select the correct hammer for the corresponding feed sizes. For primary crushing and recycled concrete, use a martensitic blow bar with ceramic inlay. 
Remember when using larger feed sizes, they'll need a blow bar with greater breaker resistance. 

The Moisture
When there is more moisture present in the feed, the impact crusher and its blow bars wear down faster. Operators need to be cautious when using water to dust down a site.

Fine
When there are a large number of fines inside the feed, the blow bars wear down quite quickly.