To make china high precision cnc machining metal mechanical parts, it may use the Brinell hardness scales. The Brinell hardness scale is most generally used to assign hardness of nonferrous metals and prepares before machining and warmth treatment. Brinell hardness analyzers make a space on a bit of material with a 10-mm-width tungsten carbide ball. (Materialsother than metals can be tried utilizing a 5-mm ball.)
A 500-kg, 1500-kg, or 3000-kg weight or burden is utilized to press the ball into the material relying upon the material sort being tried. Harder materials require the utilization of heavier loads. After a hold up of 10-30 seconds, the heap is evacuated and the ball is withdrawn. The breadth of the impression is then contribution to a standard equation to figure the Brinell hardness number.
Brinell hardness numbers are contracted as either HB (Hardness Brinell) or BHN.
Prepares would by and large be tried utilizing the 3000-kg load. Brinell hardness numbers for prepares normally run from around 100 for delicate low-carbon prepares to more than 700 for completely solidified instrument prepares.
Performing Brinell Hardness Testing
There are numerous varieties of Brinell hardness analyzers, however two essential highlights can be utilized to order them. Like Rockwell analyzers, the main contrast is whether the analyzer is an open circle or shut circle type. This alludes to how the heap is applied. Open-circle type analyzers use loads or water powered strain to constrain the ball into test parts.
Shut circle analyzers utilize a microchip controlled engine to drive the ball into the material being tried. Another distinction identifies with how the space is estimated. The standard kind of analyzer performs just the activity of making the space. After the space is made, it should then be estimated with a Brinell magnifying instrument and the BHN determined utilizing the standard recipe. The second sort of analyzer plays out the test, consequently gauges the space, and yields the HB number on a gage or readout.
Before the hardness test is played out, the example to be tried must be perfect and liberated from oxidation and scale. This should be possible by machining, documenting, or cleaning with rough paper. On the off chance that there is oxidation, surface stamps, or knocks, bogus readings can result. A perfect surface additionally makes it simpler to quantify the space if the test is done on a manual analyzer.
The cnc precision machining companies playing out a Brinell hardness test is like playing out a Rockwell test. Here are the essential advances. Allude to the producer’s guidelines for insights concerning a particular model.
- Load the test part on the iron block and preclamp by raising the hoisting screw.
- Set the power of the significant burden. Contingent upon the model, this will be finished by changing water driven or gaseous tension, insalling the best possible loads, or setting an electronic control.
- Apply the heap. Contingent upon the model, this is finished by pulling a switch to apply the heap through water driven or pneumatic stress, flipping a switch to deliver the weight, or squeezing a catch on the electronic control. Most models will apply the heap, delay for a preset measure of time, and afterward withdraw the heap.
- Unclamp the example part by bringing down the hoisting screw.
On manual models, measure the space with a Brinell magnifying instrument, and afterward utilize the Brinell equation to compute the BHN. On programmed models, basically read the BHN on the showcase of the control.
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