Is a screw valve suitable for dispensing high-viscosity glue?

**Screw ValveIs it suitable for dispensing high-viscosity glue?**

In modern industrial production, the dispensing process is an important means of connecting, sealing, fixing, and protecting electronic components, and its accuracy and stability are crucial to product quality. With the continuous advancement of technology, dispensing equipment is also constantly upgraded to adapt to different viscosities and types of glue. The screw valve, as a precision dispensing valve, is particularly noteworthy in its application for high-viscosity glue dispensing. This article will discuss in detail the working principle, advantages, limitations, and applicability of the screw valve in high-viscosity glue dispensing.

**I.Working Principle of the Screw Valve**

The screw valve is a commonly used fluid control device, mainly composed of a screw and a stator (or nut). The working principle of the screw valve is based on the relative motion between the screw and the stator. By adjusting the rotation speed and direction of the screw, the flow rate and direction of the fluid (such as glue) can be controlled. When the screw rotates, the volume of the cavity inside the stator changes, thereby pushing the glue to move along the screw axis. This working principle gives the screw valve high precision and stability in controlling fluid flow.

**II.Advantages of the Screw Valve**

1. **Accurate Measurement, Stable Glue Dispensing**: The screw valve engages the outer screw and inner screw, with a fixed displacement for each screw pitch, allowing for precise calculation of the glue output for each full rotation. This measurement method ensures high accuracy and stability during the glue dispensing process, making it very suitable for situations requiring precise control of glue quantity.

2. **Suitable for High-Viscosity Glue**: Traditional pneumatic dispensing valves may experience unstable dispensing or slow speed when the air pressure is low or the glue viscosity is too high. However, the screw valve, driven by a motor to rotate the screw, calculates the glue output based on volume, unaffected by the glue viscosity. Therefore, the screw valve has significant advantages in high-viscosity glue dispensing.

3. **Suitable for Glue Containing Fillers**: Some special glues may contain fillers that could corrode the rubber material of the stator. However, the material selection for the screw valve is relatively flexible, and as long as appropriate materials are chosen, corrosion issues can be effectively avoided.

**III. Limitations of the Screw Valve**

Although the screw valve has many advantages in high-viscosity glue dispensing, it also has some limitations:

1. **Not Suitable for Fast-Curing Glue**: For fast-drying glues, anaerobic glues, and other fast-curing adhesives, the screw valve may not be suitable. This is because these glues can quickly cure upon contact with the valve body, leading to the screw valve being unable to operate normally or even becoming unusable.

2. **Caution with Corrosive Glues**: Although the material selection for the screw valve is relatively flexible, caution should still be exercised in choosing materials for certain highly corrosive glues to avoid damage to the valve body.

**IV. Applicability of the Screw Valve in High-Viscosity Glue Dispensing**

High-viscosity glues typically have lower fluidity, which makes traditional pneumatic dispensing valves prone to clogging or instability during the dispensing process. The screw valve, driven by a motor to rotate the screw and calculating the glue output based on volume, is unaffected by glue viscosity, making it very suitable for high-viscosity glue dispensing needs. Additionally, the precise measurement and stable dispensing characteristics of the screw valve also provide a broad application prospect in high-precision dispensing scenarios.

In practical applications, screw valves have been widely used in areas such as solder paste dispensing, solder paste welding, and chip packaging for high-viscosity liquid coating. These application cases fully demonstrate the reliability and effectiveness of screw valves in high-viscosity glue dispensing.

**V. Conclusion**

The screw valve, with its accurate measurement, stable glue dispensing, and suitability for high-viscosity glue, has significant applications in high-viscosity glue dispensing.