Having worked in the dispensing machine industry for many years, I have accumulated substantial experience in valve design and flow control. The valve is a core component of a dispensing system, directly affecting the continuity, uniformity, and maintenance convenience of the adhesive flow. On production lines, I often observe that different valve types exhibit clear differences in flow channel design, sealing methods, and power transmission, all of which ultimately determine dispensing stability and efficiency.
The screw valve was the first type I encountered. It relies on threaded rotation to push adhesive through a relatively long flow channel, offering stable performance for continuous dispensing or large-volume applications. For example, in PCB assembly or chip packaging lines, screw valves help ensure consistent adhesive thickness between pads, reducing rework. However, low-viscosity adhesives may occasionally experience backflow. In my experience, adding a check mechanism or slightly reducing pressure within the valve structure can effectively improve flow stability in such cases.
Needle valves have short flow channels and fast response, making them ideal for micro-volume, high-precision dispensing, such as microelectronic components or small medical device parts. I once worked with needle valves in a medical syringe production line, where stable dispensing was required even at low temperatures. The design of the needle seat and return spring greatly influences output consistency. Through practical adjustments and structural optimization, it is possible to manage adhesive viscosity variations and maintain relatively uniform dispensing.
Jet valves are commonly used for high-speed dispensing or automated assembly lines. They eject adhesive rapidly by fast opening and closing. Flow fluctuations are common under high-frequency operation. In my hands-on experience, precise matching of valve core material, drive pressure, and spring stiffness, along with regular maintenance, is critical for achieving long-term stable operation. Understanding the valve’s structural characteristics is essential to achieve reliable dispensing performance in high-speed production environments.
Beyond the valve type itself, flow channel shape, sealing method, and power unit compatibility also affect stability. Different adhesives, such as epoxy, silicone, or UV glues, and production pace variations need to be considered when selecting or designing valves. My experience suggests that combining the specific process requirements with adhesive characteristics, selecting the appropriate valve type, and optimizing structure and maintenance practices can significantly enhance dispensing stability and reliability.
In summary, screw valves suit continuous large-volume dispensing, needle valves are ideal for micro-volume high-precision applications, and jet valves work best for high-speed automated production. As a professional with many years in the industry, I know that every valve type has its advantages and limitations. Proper selection and design optimization are key to achieving efficient and stable dispensing on the production floor.