Two test conditions:
Condition 1: Client uses our Hybrid wheel to replace competitor's Hybrid wheel.
Condition 2: Client uses our Hybrid wheel to replace resin bond wheels
Condition 1: Client uses our Hybrid wheel to replace competitor's Hybrid wheel.
Set linear speed to be 14-20m/s, which is suitable to offer the best performance.
Use the same parameters as the competitor's Hybrid wheels, same infeed, transverse feed, coolant pressure and others. Check the machine load and compare it with the competitor'
If machine load up, it means our wheel is not as sharp as competitor's. We can lower the linear speed to make machine load same as competitor's. It will take a little longer time to finish same work. The client have to check if our wheel can meet their requirements of production.
If machine load down, it means our wheel is sharper than competitor's. We can increase the linear speed until the machine load is same as competitor's. It will save more time and improve efficiency. Please note that the client has to check the roughness of tool surface, also needs to check if there is a chipping edge problem. We should reduce the speed before the processing quality going worse.
After few times, the client will get the optimum parameters that our wheel can offer the best performance and meet their requirements at the same time.
After testing sharpness, the client will continue to test our hybrid wheel in volume production if it can meet the requested performance.
With the optimum process parameters for our hybrid wheel, the client will know how many pieces of tools our hybrid wheel can grind before next dressing.
There are different processes to repair hybrid wheel after being used, truing and dressing, we also call 'dressing' as opening.
After grind some tools, the carbide scraps or alloy powder will stick to diamond grits. There is no new edges of diamond grains exposed to grind material. The machine load will increase with the hybrid wheel loading up. Opening means that we use dressing stick to clean the surface of hybrid wheel.
Usually we use dressing stick with finer grit, like D54. Use medium pressure with 1000 RPM to dress the hybrid wheel. After 1 min dressing, there will be new edges come out.
Truing is for ensure the diamond rim is a concentric circle and a flat surface with sharp corners. The corner radius of the wheel may become larger after few days. It will cause that the tolerance of tools can not meet requirement. We have to remove the wheel offline and true the rim to be concentric circle.
We always use WA or SiC wheel to make truing. Please check below parameters:
In feed 0.1mm and transverse feed 400 mm/min.
WA wheel speed 16 m/s and Hybrid wheel 5 m/s.
The truing frequency is a very important index to compare with other hybrid wheels. If the hybrid wheel need to be trued frequently, the client have to stop the machine and remove the wheel offline. It will seriously influence their production efficiency.
The number of finished tools in 1 truing cycle is a very important index.
After the client comparing the sharpness and truing frequency, we will made records and get ideas how to improve the wheel performance according to their feedback.
Condition 2: Client uses our Hybrid wheel to replace resin bond wheels
To compare with resin bond wheels. Our aim is that help clients to improve processing technique and increase efficiency. The hybrid wheel will save the clients time and costs.
Set the suitable speed, 14-20 m/s.
Choose the suitable infeed according to diameter of carbide rod.
For drills with diameter less 12mm, we suggest that the 1stcut(infeed) at 3-4.2mm and transverse feed at 150-80 mm/min. But the 1st cut of resin bond wheel is only 1-2 mm. And the transverse feed is about 50-80 mm/min.
For drills with diameter 12-20 mm, we suggest that the 1stcut at 2.5-3.0 mm and transverse feed at 100-80 mm/min.
For drills with diameter over 20 mm, we always set the 1stcut at 2.0 mm and transverse feed at 80-60 mm/min.
For end mills with diameter less 12 mm, we suggest that the 1stcut at 2.5-3.0 mm and transverse feed at 180-100 mm/min.
For end mills with diameter 12-20 mm, the 1stcut can be at 3-6mm. We always set transverse feed at 100-50 mm/min.
For end mills with diameter over 20 mm, we recommend the 1stcut at 6-7 mm and transverse feed at 50-30 mm/min.
For straight flute tools, there is only 1 cut. The infeed is about 5-12 mm. The transverse feed is about 50-30 mm/min.
All of infeed and transverse feed need to be adjusted according to client's machine, length of carbide rod, requirements of process and quality. The client will get the optimum process parameters of our hybrid wheel refer to their experience.
With best process parameters, then test how many pieces of tools the wheel can grind in 1 dressing cycle.
After all tests, the client will get the result. We will give our suggestion about how to improve the wheel performance according to the test results.
PS:
Please lower RPM if there is noise in grinding process.
If there is smoking in process, please use dressing stick clean the surface of grinding wheel or set suitable parameters.
Please check how many tools the wheel already grind if the machine load beyond limit. The improving solution for the first tool and the Nth tool are different.
If the wheel need to be trued frequently, please check which problem leads to this issue, machine load increase or big wheel corner radius, we have different improve actions for these 2 problems.