The possible causes and solutions for the M3 cross screw punch with medium are as follows:

I. Core Cause Analysis

1. The material of the screws is impure or contains impurities, resulting in insufficient strength and making them prone to cracking under high pressure. 

The material hardness does not meet the standard (for example, the hardness of the punch should be controlled at 58-62 degrees, and copper screws are

 softer and more prone to slipping), and it cannot withstand the impact force.

2. Mold and process defects: Punch quality: The length, diameter or hardness of the punch does not meet the standards, or there are wear and cracks. 

Mold matching: Improper selection of one-stroke dies and two-stroke dies (such as using hexagonal Wasps head dies to make coil heads) leads to poor forming. 

Lubrication issues: Poor quality of lubricating oil or uneven application increases friction and causes local overheating.

3. Operation and parameter errors: Excessive pressure: The distance between the upper and lower pressing wheels of the tablet press is too small, 

and the pressure exceeds the limit that the punch can withstand. Improper machine adjustment: The installation positions of the first and second punches are off, 

causing the screw heads to be eccentric or cracked. Excessive speed: The tapping or stamping speed is too high, the cutting fluid is insufficient, and the chip removal 

is not smooth.

4. Design structure Issues ** - The channel design of the 11-shaped screw with a medium may lead to stress concentration, especially at the medium part where 

cracking is prone to occur. A head that is not round or has a double-layer structure may burst due to incomplete molding.

Ii. Solutions

Optimize the material and hardness, select high-purity and high-strength screws and wires, and ensure uniform material free of impurities.

Adjust the hardness of the punch to 58-62 degrees (for copper screws, it can be appropriately reduced to 58-60 degrees) to enhance impact resistance.

2. Improve molds and processes. Mold matching: Select the corresponding die based on the screw head type to avoid mixed use. Lubrication optimization: 

Use high-quality lubricating oil to ensure adequate lubrication during the stamping process. Forming adjustment: Check the installation positions of the first and 

second punches to ensure that the head is fully formed and free of eccentricity.

3. Adjust the operating parameters. Pressure control: Adjust the distance between the upper and lower pressing wheels of the tablet press to reduce the 

pressure to within the range that the punch can withstand. - Speed control: Slow down the tapping or stamping speed to ensure that the cutting fluid is fully 

cooled and chips are removed. Coaxiality correction: Use a floating tapping chuck to ensure the coaxiality of the tap and the bottom hole.

4. Design optimization: Modify the eleven-shaped groove design to reduce stress concentration points. Adjust the structure of meson sites to enhance local strength.

5. Quality inspection and Maintenance, punch inspection: Regularly check the wear condition of the punch and replace cracked or excessively worn punches

 in a timely manner. Material inspection: Conduct hardness and composition tests on screws and wires to ensure they meet the standards. Process verification:

 Verify the effect of parameter adjustment through trial production and continuously optimize.

Iii. Suggestions for Implementation Steps

1. Short-term measures: Immediately inspect the quality of the punch and replace the unqualified ones. Adjust the pressure parameters of the tablet press to 

reduce the impact force. Increase the amount of lubricating oil used to ensure a smooth stamping process.

2. Medium-term measures: Communicate with suppliers to optimize the material and hardness of screws and wires. Redesign the eleven-shaped groove to 

reduce stress concentration. Train the operators and standardize the machine adjustment process.

3. Long-term measures: Establish a quality inspection system and conduct regular spot checks on screws and punches. Introduce automated equipment to 

reduce human operational errors. Continuously improve the process to enhance production stability and product qualification rate.