The Manufacturing Technique Study On LNG Marine Plywood

At present, the industry of LNG ship is in a high-speed development period.The consumption of plywood to make a LNG ship is very large.So it is beneficialthat produce durable plywood to promote the development of the LNG carrier andthe product structure adjustment of timber processing enterprises that develop inthe direction of high technology and high additional value.Poplar is one of mainplantation wood species in our country. It is meaningful for our country to makefull use of plantation wood resources, raise the utilization ratio of timber anddevelop the high strength and weather resistance marine plywood with fast growingplywood.This study investigated the veneer of fast growing poplar and hotre-pressing was carried out to make faced plywood.Hot pressing parameters wasdiscussed on its physical and mechanical properties and surface properties.theconclusions were listed as following:1)According to the influence of thermal press on plywood density,Plywooddensity conform to product requirements when thermal parameters weretemperature of130℃,time of1.0mm/min and pressure from0.8MPa to1.6MPa.2)The higher Plywood hot-pressing temperature, the faster increase of centrallayer temperature, so the center layer of adhesive curing speed is faster.3)Through the study on the four levels of hot-pressing temperature andhot-pressing time influence on the bond strength of plywood surface and core layer,the influence of hot-pressing temperature on the bond strength of plywoodsurface and core layer is significant and on the bond strength of core layer plywoodis more significant.the influence of hot-pressing time on the bond strength ofplywood surface layer is non-significant but the influence of hot-pressing time onthe bond strength of core layer plywood is significant.the bond strength of corelayer plywood is increased with the rising of hot pressing time.4) Using L9（34）orthogonal test method, the thermal process of base plywoodare discussed.The influence of hot-pressing temperature,hot-pressing time,thermalpressure and glue spread amount on Physical and mechanical properties of baseboard.By variance and extreme difference analysis on test results,the optimumthermal process parameters on base board were:hot-pressing temperature of130℃,mat pressure of1.2MPaand glue spread amount of260g/m~2.5) By hot-pressing time impact on the substrate thickness and Optimization ofhot pressing time,the optimum hot-pressing time was1.2min/mm. 6)By the study on the four levels of hot-pressing temperature and hot-pressingtime influence on Surface properties and physical and mechanical properties offaced plywood,the optimum hot-pressing temperature was140℃and the optimumhot-pressing time was6min. All the properties which production demanded weregood by the optimum hot-pressing process parameters validation.