Study On Preparation And Performance Of Wood-based Winding Pipe

Pipeline water transmission is the most commonly used means of water transmission in water supply and drainage engineering.It has many advantages,such as convenient construction,high transportation efficiency,less loss along the way and less environmental damage.Traditional water pipelines include concrete pipes,metal pipes,plastic pipes and so on.Traditional water pipelines have different degrees of high energy consumption,high cost,poor aging resistance and other shortcomings.Therefore,the development of energy-saving and environmental protection of new water pipelines is of great significance to promote Chinese water engineering construction and ecological resources construction.This paper by artificial fast-growing poplar veneer as the basic tectonic units,through the winding technology development of wood base wound pressure pipeline,system applicable to the wood base pipe winding process is studied in the resilience of excellent low temperature in the biomass base curing adhesive preparation,cypress wood veneer layer number of twisting(structure layer thickness)of pipe ring stiffness,ring to the tensile strength and the influence law of seepage water pressure;A small wood-based winding pipe production equipment was developed.The influence of heat and cold cycle treatment on the interface between pipe structure layer and inner and outer protective layer is analyzed experimentally.The results are as follows:(1)In this paper,peanut shell liquefaction was used to prepare modified phenolic resin adhesive with high solid content through copolymerization.Single factor test was used to study and analyze the molar ratio of peanut shell liquefaction products to formaldehyde,and the influence of reaction time and temperature on resin properties.It is found that the best preparation process of peanut shell liquefaction resin is the molar ratio of formaldehyde to peanut shell liquefaction is 1.2,the reaction temperature is 85°C,and the reaction time is 120 min.The peanut shell liquefied resin prepared under this condition has good fluidity and stability,and the viscosity is not too large,which can meet the application requirements of winding pipe adhesive.(2)In order to explore the influence law of structural layer number of wood-based winding pipe on the circumferential tensile strength,the universal mechanical testing machine was used to carry out mechanical tests on wood-based winding pipe with different structural layer number.The results showed that:The average circumferential tensile strength of the wood-based winding pipe with 6structural layers is 19.21 MPa,that of the wood-based winding pipe with 8 structural layers is19.84MPa,and that of the wood-based winding pipe with 10 structural layers is 23.34 MPa.The average tensile strength of wood-based winding pipe with 12 structural layers is 27.69 MPa.As can be seen from the stretch-displacement curve,the slope of the curve on the tensile curve increases gradually at the beginning of stretching.With the increase of tensile load,the fixture and the sample are fully fitted without any gap,and the tensile curve has a significant elastic deformation stage.With the increase of the number of structural layers,the circumferential tensile strength also shows a gradually increasing trend.When the number of structural layers increases from 10 to 12,the circumferential tensile strength increases the most,reaching 18.6%.(3)In order to explore the influence law of wood-based winding pipes with different structural layers on the ring stiffness,mechanical test analysis was carried out on wood-based winding pipes.The average ring stiffness of pipelines with six structural layers was 8385.12 N/m~2,and that of pipelines with eight structural layers was 11139.01 N/m~2.The mean ring stiffness of 10-layer and12-layer pipelines is 14464.89 N/m~2 and 23954.37 N/m~2respectively.The ring stiffness load-displacement curves of the pipe at each structural layer show that the pipe deformation is elastic deformation when the pipe diameter starts to change.The maximum load carried by the wood-based winding pipe increases with the increase of the structural layer,and the ring stiffness also increases significantly with the increase of the number of structural layers.Among them,when the structure layer increases from 10 to 12,the increase of ring stiffness is the largest,65.6%.(4)Hydrostatic pressure retaining tests were carried out on pipelines with different structural layers to analyze the influence of different structural layers on wood-based winding pipelines.When the test pressure was 1.5 times of the pressure level and the pressure was held for 2 min,no leakage occurred in the body and connecting parts of each layer of wood-based pipeline.The water pressure in the pipeline increases with the increase of the number of structural layers,and the pressure time also increases.The internal water pressure of the pipeline with 6,8,10 and 12 structural layers is2.05 MPa,2.56 MPa,3.08 MPa,3.68 MPa.(5)in this paper for composite laminated plate after processing,the interface of psychro-thermal cycles of hot and cold cycle after processing of composite laminated plate interface between the layers of SEM,one study found that a small amount of hot and cold cycle will not affect the composite laminated plate interface,only cycle number increased to 30 times,after psychro-thermal cycles interface will appear tiny crack.(6)This paper analyzes the law of the influence of hot and cold cycles on the shear strength and laminar shear strength of wood-based pipes.Through the experimental study,it is found that the shear strength of the interface layer of composite laminates increases first,then decreases,and reaches the maximum value when the hot and cold cycles reach 20 times.After 30 cycles,the interfacial shear strength of the composite is 22.6 MPa.With the increase of the number of hot and cold cycles,the bending strength of composite laminates increases first and then decreases.After 30cycles of hot and cold,the bending strength of the composite remains as high as 131.4 MPa.