Intelligent QCS System for Writing Paper Machine
In a paper manufacturing machine, controlling basis weight and moisture is essential for consistent paper quality and machine efficiency. Our paper mill equipment integrates a fully digital QCS system designed for the demanding conditions of writing paper and newsprint production. The paper production equipment uses a non‑contact Kr85 basis weight sensor with a US‑made ionization chamber and military‑grade components, ensuring long‑term stability and low radiation.
The microwave moisture sensor employs dual‑frequency scanning, making it insensitive to paper color, filler content, and temperature changes. The scanning frame features a ┝‑shaped column and H‑shaped manganese steel structure with dual guide rails and four sliders, offering low deflection and high mechanical precision. A Z‑axis vertical distance sensor continuously measures the probe gap and compensates for thermal deformation caused by temperature differences between upper and lower beams. A separate horizontal misalignment compensation system corrects for lateral movement during scanning.
The measurement window is protected by a spiral constant‑temperature air column and embedded DC24V heaters to prevent condensation and dust accumulation. All critical moving parts are imported from Germany, Japan, and Taiwan, including IGUS flexible cables, MEGADYNE synchronous belts, FESTO pneumatic components, and HIWIN linear guides. The control system uses Siemens S7‑1500 PLC and PCS7 software, with a field touchscreen for local operation. The operator station runs on Windows 10 and provides real‑time displays of cross‑direction profiles, historical trends, and automatic reports.
Performance Data of Our Writing Paper Machine
| Specification | Value |
|---|---|
| Application | Writing paper, newsprint, 100‑300 g/m² |
| Web width | 2640 mm |
| Operating speed | 500 m/min |
| Basis weight sensor | Kr85, 200 mCi, 20‑1000 g/m² range |
| Basis weight 2σ accuracy | ≤0.15 g/m² or ±0.15% |
| Moisture sensor | Microwave, 0‑20% range, dual‑band |
| Moisture 2σ accuracy | ≤0.15% |
| Resolution (basis weight) | ≤0.05 g/m² (2σ) |
| Resolution (moisture) | ≤0.02% (2σ) |
| Response time (basis weight) | ≤5 ms |
| Response time (moisture) | ≤4 ms |
| Scanning speed range | 50‑550 mm/sec, variable frequency |
| Positioning accuracy | ±0.25 mm |
| Upper‑lower sensor gap error | ≤0.10 mm |
| Horizontal error | ≤0.15 mm |
| Paper edge measurement accuracy | <1 mm |
| Control improvement | ≥60% for both basis weight and moisture |
| Operating temperature (sensors) | 0‑85°C |
| Relative humidity | 5‑90%, non‑condensing |
| Air supply requirement | >50 L/min, 3 kg/cm², oil‑free, dry |
Leizhan provides paper mill plant machinery with integrated QCS systems that deliver proven performance. Our complete paper mill line solutions include everything from the headbox to the reel, and we partner with leading automation suppliers to ensure your paper making line achieves tight quality control. We offer full engineering, installation guidance, and commissioning support. Contact us to build a turnkey paper production line that consistently produces high‑grade writing paper and newsprint.
Contact: leizhanworld@gmail.com
