What about the noise of NC punch?
From the development of traditional punch to now CNC punch, the stamping production of many factories has been improved.
CNC punch greatly improves the production level, improves the quality and accuracy of stamping parts to varying degrees, and maximizes the saving of human and material resources.
Therefore, CNC punch has gradually replaced the traditional punch stamping trend.
The main means of punch noise control is to set up punch sound insulation cover.
For enterprises with high requirements, it can also be combined with vibration damping device, sound insulation screen cover and other comprehensive treatment.
1. The foundation shall be made according to the requirements of the installation manual, and the anchor screws of the equipment shall be fully tightened to ensure the stability of the machine tool and effectively reduce the vibration;
2. The use of Shockproof foot pads can reduce the vibration of the press itself and the impact on the surrounding equipment;
3. Digging shockproof ditch can minimize the impact of punch on surrounding equipment.
The depth of the shockproof ditch must reach the scouring depth.
Starting from the punch noise source and die structure, the following points should be paid attention to in order to reduce the noise:
1. Pay attention to mold maintenance and cleaning, and keep the edge sharp.
2. After the mold is debugged, the sound insulation cover or sponge board shall be installed on the punch for sound insulation treatment.
3. Aluminum plates are padded on the surface of the upper and lower die bases for impulse buffer.
4. According to the matching accuracy between the working templates, some exhaust slots are processed.
5. The stop plate is changed into small pieces, and the stripper plate and lower formwork are changed into insert type to reduce the attack area.
6. The spring jack source of the stripper plate is changed to T-shaped ejector rod.
The spring is installed on the upper die base, and the contour sleeve is matched with the ejector rod to ensure that the stripper plate still has a certain amount of free movement when the die is opened.
7. Keep good lubrication, and the mold is free of interference and smooth.
8. Improve the accuracy of the punch and reduce the structural noise.
A buffer, vibration and noise reduction oil cylinder is installed on the workbench, the gear is lubricated with helical teeth and equipped with a gear cover, and a muffler is installed in the pneumatic system.
9. The die edge must be perpendicular to the installation surface, and the matching clearance of the male and female die edge should be reasonable.
When unloading is difficult, the lower die clearance and unloading force can be increased, and the unloading plate with soft surface can be used.
10. The shape, quantity, material and punching line of the die edge are long.
The contact surface between the die edge and the parts should not be too large.
The punch makes oblique edge step blanking, so that the cutting depth of the die is different at different positions.
The whole process realizes real cutting rather than synchronous extrusion.
How to reduce press noise?
1. Determination of reverberation time and noise value of noise source in workshop:
Reverberation time refers to the time when the indoor sound reaches a stable state.
After the sound source stops making sound, the residual sound is reflected back and forth in the room, absorbed by the wall, and the average sound energy density decreases to one millionth of the original value.
The longer the reverberation time, it indicates that the sound is reflected many times in the workshop, and the energy attenuation speed is slow.
Under the condition of the same sound source, the noise of the workshop with long reverberation time is greater than that of the workshop with short reverberation time.
2. Selection of sound-absorbing materials:
The sound insulation board consists of five parts.
The noise enters the sound-absorbing cotton through the small hole of the perforated board. One part converts the energy into heat energy through the vibration of the glass wool wire and consumes it.
The other part is isolated by the outer steel plate to achieve the purpose of absorption and separation.
The sound permeable film is pasted on both sides of the sound-absorbing cotton to prevent moisture and prevent the sound-absorbing cotton from falling off from the mesh of the inner perforated plate.
3. Sealing treatment of sound-absorbing plate:
Since the sealing treatment of the whole production line is to splice a plurality of small sound-absorbing plates into a closed body, in order to ensure the noise reduction effect, the gap between each sound-absorbing plate needs to be controlled during design and manufacturing, generally 1 ~ 2mm.
In order to prevent noise from coming out through these gaps to affect the effect of noise reduction, sealant is usually used for gap sealing.
4. Ventilation treatment:
Due to the heat generated by the operation of the equipment itself and the thermal insulation characteristics of the sound-absorbing material glass wool, the temperature inside the production line is often 3 ~ 5 ℃ higher than that outside.
During the implementation of noise reduction works, an exhaust fan is usually installed on the top of the sound insulation wall to extract the hot air in the enclosed space to form a negative pressure inside, and the external air can flow into the interior through the sound insulation wall.
When selecting the exhaust fan, select the fan with low noise to avoid affecting the effect of noise reduction.
5. Treatment of lighting equipment:
Since the interior of the equipment is isolated from the external workshop lighting after the implementation of the enclosed project, the lighting system needs to be added in the enclosed body.
In order to ensure the lighting required for production and later equipment maintenance, the design illumination is more than 500 lumens.
The lighting system in the enclosed body shall be wired separately and switched independently to ensure convenient use without affecting the original power supply system.
In addition, in order to prevent sudden power failure in the workshop, an emergency lighting system is installed in the enclosure to ensure the safety of equipment and personnel.
The outer steel plate with a thickness of 2mm plays the role of sound insulation and support, and is the outer surface of the sound-absorbing plate.
The middle part of the sound-absorbing board is made of sound-absorbing material and made of glass wool products.
It is used to absorb sound energy and is the main component of noise reduction materials.
The fiberboard is pasted on the outside of the sound-absorbing cotton to prevent the sound-absorbing cotton from falling.
The above five aspects are the measures that can be taken to reduce the noise generated by the press.
I hope it can be helpful to you.