The application advantages and selection points of pneumatic plug valve in the paper industry

In papermaking production, pulp conveying, pulping systems, black liquor recovery, and wastewater treatment all involve media with high solid content, high fiber content, and poor fluidity. During long-term operation, valves not only have to withstand wear and erosion, but also ensure stable and reliable regulation processes. Pneumatic plug valve is widely used in the industry for throttling and regulating pulp pipelines due to its compact structure, good sealing performance, and rapid action. It is an important equipment in pipeline control of paper enterprises.

1、 Structural characteristics adapted to papermaking conditions

The core difficulties of papermaking conditions lie in "high solid content" and "easy fiber entanglement". Traditional gate valves and butterfly valves are prone to jamming in high fiber slurries, while the blade gate of pneumatic plug valves can directly cut through the slurry during operation, reducing blockage. Meanwhile, its straight through flow channel design can reduce medium retention and also have a positive effect on reducing pressure loss.

Valve bodies are usually made of wear-resistant materials or lined with anti-corrosion coatings. The material scheme can be adjusted according to the specific medium, such as selecting materials with higher corrosion resistance when in contact with black liquor or alkaline solution. Cooperating with the pneumatic actuator, the opening and closing process of the blade is smooth, and there will be no vibration or impact caused by uneven manual operation.

2、 Advantages of Application in Pulp Pipeline

1. Stable regulation process

Pulp has poor fluidity and is prone to pressure fluctuations during throttling. The pneumatic plug valve has a short opening and closing stroke, controllable adjustment speed, and can smoothly switch from fine adjustment to large opening. It is suitable for fine control of thick and low thick slurry systems.

2. Reliable sealing and low maintenance

The valve seat structure often adopts flexible or metal sealing, and different sealing forms can be selected according to the composition of the slurry. The sealing surface can be replaced separately after wear, reducing downtime and meeting the continuous production needs of the paper industry.

3. Difficult to block fiber media

The blade plate structure can cut and discharge the winding material during the opening process, effectively reducing the probability of blockage. It can also maintain high flow capacity for high solid content and long fiber pulp.

4. Can achieve automated control

After being equipped with pneumatic actuators, it can be linked with the DCS system to achieve remote adjustment, opening feedback, and status monitoring, improving the automation level of the production line.

3、 Key points for selection in the papermaking industry

1. Clarify the characteristics of the medium

Pulp concentration, solid content, and fiber length all affect the selection of valve type and sealing structure. High concentration slurry should prioritize the use of wear-resistant blade plates and metal sealing forms.

2. Pay attention to the flow channel structure and flow capacity

The straighter the channel of the valve, the lower the resistance, making it more suitable for conveying slurry. When selecting, attention should be paid to the actual flow rate, pressure loss requirements, and pipeline layout conditions.

3. Matching of executing agencies

Different valve diameters and blade strokes have different requirements for the output force of the actuator, and it should be ensured that the thrust of the pneumatic actuator can be reliably closed under the pressure of the slurry.

4. Maintain convenience

The papermaking industry has numerous equipment and limited on-site space. The sealing structure that can be disassembled online and the valve seat design that is easy to replace will directly affect the cost of later use.

In summary, the value of pneumatic plug valves in the paper industry is not only reflected in their usability, but also in their suitability for less blockage, stable regulation, long service life, and easy maintenance.

Reasonable selection can significantly improve the operational reliability of pulp pipelines, reduce fluctuations and downtime in the production process, and bring stable production capacity and lower operating costs to enterprises.