What causes pneumatic injection valve adhesion?
Release time:
2025-04-23 08:00
Source:
Leica Technology
Main reasons for pneumatic nozzle clogging:
1. Improper air pressure setting
Air pressure is pneumatic nozzle one of the key factors driving its operation. When the driving air pressure is too low, the force of the compressed gas acting on the lower surface of the piston is insufficient to allow the piston to overcome the spring force and lift completely. The speed at which the impactor moves downward may be less than the critical injection speed, resulting in incomplete atomization and ejection of the fluid, which instead flows out of the nozzle and accumulates at the outlet, eventually causing clogging. Conversely, when the driving air pressure is too high, although the impactor stroke and injection speed will increase, the excessive impact force may cause uneven dispersion of the fluid during injection, producing satellite droplets, which is also a form of clogging. Therefore, reasonably setting the air pressure is key to preventing clogging.
2. Nozzle misalignment
Nozzle alignment is pneumatic nozzle crucial to the injection effect. If the nozzle is not adjusted to the optimal position during alignment, it may cause the fluid to deviate from the predetermined trajectory during injection, failing to accurately reach the target position, and accumulating around the nozzle, causing clogging. In addition, improper alignment may also cause poor sealing between the nozzle and the valve seat, causing fluid leakage during injection, further exacerbating clogging.
3. Nozzle contamination
Nozzles are easily contaminated by dust, oil, and other pollutants during use. These contaminants not only affect the injection effect of the nozzle but may also cause nozzle blockage or wear, preventing the fluid from being completely ejected during injection, thus forming clogging. Therefore, regular cleaning of the nozzle is one of the important measures to prevent clogging.
4. Influence of fluid properties
The viscosity, surface tension, and other properties of the fluid also affect the injection effect of the pneumatic injection valve. When the fluid viscosity is too high or the surface tension is too large, the fluid may not be easily dispersed during injection and is easily accumulated around the nozzle, forming clogging. In addition, some fluids may undergo chemical reactions or phase changes under specific conditions, causing changes in fluid properties, which in turn cause clogging.
Measures to prevent clogging of the pneumatic injection valve:
1. Reasonable air pressure setting
According to pneumatic nozzle the model and fluid properties, reasonably setting the air pressure is crucial for preventing clogging. In actual operation, the optimal air pressure range can be determined through experiments and observations to ensure that the fluid can be completely atomized and ejected, avoiding clogging.
2. Regular nozzle calibration
Regularly calibrate the nozzle to ensure that it is in the optimal position and that the seal between the nozzle and the valve seat is good. During calibration, strictly follow the operating procedures to avoid clogging caused by improper calibration.
3. Regular nozzle cleaning
Regularly clean the nozzle to remove contaminants and residues and keep the nozzle clean and unobstructed. During cleaning, use appropriate cleaning agents and tools to avoid damaging the nozzle.
4. Select appropriate fluids
Select suitable fluids based on production needs and avoid using fluids with high viscosity or high surface tension. If necessary, methods such as adding diluents or surfactants can improve fluid properties and enhance the injection effect.
Related News
How can daily maintenance help extend the service life of a valve body?
As a precision component that operates at high frequency, the precision dispensing valve requires scientific daily maintenance to extend its service life and maintain dispensing accuracy. Shenzhen Laike Technology has compiled the following key maintenance points for you: Daily cleaning is crucial and should not be overlooked. After finishing work, promptly remove any residual adhesive from the exterior of the valve body, especially around the nozzle and plunger area. Once cured, adhesive can cause blockages or wear, affecting subsequent use. It is recommended to gently wipe with a suitable cleaning solvent, taking care not to damage the seals. Regularly inspect sealing components—seals and other parts will naturally degrade over time during prolonged operation. We recommend checking their condition periodically based on usage frequency. If you notice signs of hardening or wear, replace these components promptly to prevent adhesive from seeping into the valve body and causing more serious damage.
The stringing issue during the dispensing process is often closely related to fluid properties, equipment parameters, and process settings. Drawing on years of industry experience, SZLKTE has compiled and optimized key points for you: Fluid temperature control is crucial. Proper heating can reduce the viscosity of the adhesive, improve its flowability, and minimize stringing and trailing. SZLKTE’s dispensing valves can be equipped with precision temperature-control modules to ensure that the fluid remains in a consistently stable working state. The back-suction parameters must be finely adjusted. The negative-pressure back-suction applied at the moment the glue dispensing stops can effectively cut off the adhesive flow, preventing dripping and stringing. We recommend gradually adjusting the amount and speed of back-suction according to the adhesive’s viscosity until you find the ideal balance.
SZLKTE takes a multi-dimensional approach to ensure zero errors and long service life for its products even under high-speed, continuous operation. The piezoelectric valve series employs piezoceramic actuation technology; its non-contact drive design eliminates mechanical wear common in traditional solenoid valves, enabling a service life of over one billion cycles. At the same time, these valves deliver millisecond-level response times, completely eliminating trailing and stringing issues. The needle valve KC-9870, on the other hand, features a specially engineered, wear-resistant material for its needle component, offering exceptional resistance to abrasion and corrosion. Even in industrial environments with prolonged operation, this valve maintains outstanding stability. Moreover, its components can be quickly disassembled and maintained, significantly reducing production downtime.
Contact Dispensing vs. Non-Contact Jetting Valves: How Should You Choose for Micron-Level Processes?
Contact dispensing involves the needle making physical contact with the substrate surface to apply the fluid. Its main advantage lies in its strong adaptability to high-viscosity fluids and relatively controllable dispensing process. However, since it requires coordinated movement along the Z-axis, the dispensing speed is limited. Additionally, there is a risk of the needle colliding with and damaging the workpiece or deforming the needle itself. Therefore, careful evaluation is necessary when applying this method in miniaturized packaging scenarios. In contrast, non-contact jetting valves use a driving mechanism to rapidly spray adhesive onto the workpiece surface without any physical contact between the needle and the substrate. This feature makes them ideally suited for substrates with uneven surfaces or those that are fragile. They excel in micron-scale processes such as bottom-fill applications for chips and precision coating. The jetting method eliminates the need for Z-axis movement, significantly boosting production efficiency while also avoiding common issues associated with contact dispensing, such as stringing and trailing.
The stability of the piezoelectric valve dispensing process directly determines product quality. Common issues such as uneven dispensing, stringing, and glue leakage can be effectively addressed through parameter adjustments and optimized matching. Laike’s piezoelectric valves support multi-level parameter adjustments, enabling precise matching of pressure, injection frequency, and nozzle aperture according to the specific characteristics of different fluids.
Blocking the hole is Piezoelectric valve The most common failures in dispensing operations are often caused by fluid solidification, residual impurities, and nozzle wear, which directly affect dispensing accuracy and efficiency. Given the structural characteristics of piezoelectric valves, these issues can be addressed in three steps: “diagnosis—cleaning—inspection.” First, stop the machine and visually inspect the nozzle for obvious glue deposits or foreign objects, determining whether the blockage is temporary or a persistent issue caused by nozzle wear.
MENU
Quick navigation
SZLKTE technology
Company Address
Rm 315, Zone E, Bldg 7, Hengda Shishang Huigu, Longhua District, Shenzhen China