Based on the traditional surface sizing methodssuch as dip sizing and roll coating technology,
film transfer surface sizing was newly developedby China’s paper machinery suppliers, such asShashi Light Industry Machinery Co., Ltd (SLMC)and Shandong Changhua Machinery TechnologyCo., Ltd.
The modular bar film transfer equipmentdeveloped by SLMC meets the needs for papermills to transform the dip sizing type to a filmtransfer sizing equipment. And modularizationreduces the transformation period and expenses.Figure 4 shows an example of the transformationof Hunan Xiangjiang Paper Co., Ltd by SLMC--a 3300/600 dip sizing type to a film transfersizing machine. Additionally, SLMC also providedShandong Tranlin Paper Co., Ltd with a 6100/1200bar-type film transfer sizing machine.
Curtain coating has become a hot topic of researchthanks to its outstanding features compared withthe traditional blade coating and metered sizingpress coating. The application of curtain coatinghave extended from specialty paper to other papergrades, especially the coated ivory paperboard,light-weight coated paper, kraft cardboard and
The curtain coater (Figure 5) developed by SLMChas been installed on a coating machine in ChinaNational Pulp and Paper Research Institute(CNPPRI), meeting the requirements for curtaincoating pilot test at an operating speed of 800m/min.
The EvenCurtain coating machine manufactured bySLMC is suitable for the paper machines with widthof 880-6000mm and operating speed of 1800mm/min. It can be applied in the coating of most typesof paper grades, and meets different requirementsof operating speed and coating demands. It alsosatisfies the use of high solid content coatings.The EvenCurtain coating is also featured withaccurate coating lip straightness (±0.004mm), highpolishing degree of f low channel(≤Ra0.02μm),good coating coverage, and accurate coatingweight control in both cross direction(≤±0.5%) andmachine direction, as well as excellent operatingstability.
When it comes to the tissue machine, cast ironYankee dryer is now being gradually replaced bythe steel Yankee dryer. Compared with iron, steelhas the advantages in toughness, heat conductionand safety performance. The steel surface coatedwith hard alloy is much harder than cast iron. Thecarbide coating is able to improve the sheet qualityand prolong the lifetime of dryers and maintenancecycle. It is of great signif icance for energyconservation because the cylinder thickness of thesteel dryer can be reduced by about 30%, whichmeans that the heat conducting efficiency can beincreased under the same condition.
Nowadays, advanced and world-class steel Yankeedryers have been developed by some Chinesemachinery suppliers, such as Shandong XinhePaper-making Engineering Co., Ltd and LiyangJiangnan Dryer Manufacture Co., Ltd., which iswidely applied in the paper industry of China andthe globe.