39results about How to "Improve overall strength-to-weight ratio" patented technology

The invention discloses a preparation method of an organic and inorganic wood composite material, relating to the preparation method of a composite material and solving the problems that the wood composite material prepared by the traditional method has poor durability and mechanical property. The method comprises the following steps of: firstly, pre-polymerizing a monomer; secondly, preparing dilute sol; thirdly, impregnating the wood with the dilute sol under the vacuum-pressurizing condition; and fourthly, heating the impregnated wet wood to obtain the organic and inorganic wood composite material. The organic and inorganic wood composite material has higher strength-to-weight ratio; and compared with the wood, the hardness, the wearing resistance, the bending strength, the elastic modulus, the parallel-to-grain compressive strength and other mechanical properties of the organic and inorganic wood composite material are improved by 5 times to maximum extent; and the dimensional stability and the antiseptic property of the organic and inorganic wood composite material are improved by over 50-70 percent. In addition, the duality test shows that the thermal stability and the weather resistance of the organic and inorganic wood composite material are remarkably improved.

The invention relates to the field of plywood preparation, in particular to a high-strength environment-friendly plywood and a manufacturing method thereof; including: veneer surface pretreatment, fiber cloth gluing and plywood preparation steps; the invention adds a layer of fiber in the middle of the composite board After modification, this kind of fiber cloth has excellent characteristics such as high strength-to-weight ratio, high temperature resistance, corrosion resistance, aging resistance, and fatigue resistance. It can effectively improve the physical strength of plywood, and not only maintain the excellent characteristics of the original materials, Complementary advantages can also be achieved, and the advantages of fiber cloth and wood materials can be fully utilized to improve the strength of plywood, forming a new type of high-strength plywood material with small variability, high strength-to-weight ratio, and aging resistance; the adhesive used in the present invention is The environmentally friendly adhesive does not contain free formaldehyde and has no formaldehyde release problem. It is a kind of plywood that can be safe and environmentally friendly. It can be safely used in home decoration, furniture manufacturing, load-bearing materials and other fields.

The invention belongs to the field of civil engineering and discloses a method for compound reinforcement of a wooden beam. The method is characterized in that at the bottom of the wooden beam (1), fiber cloth (3) is adhered, a base layer (5) is arranged, a bamboo board (2) is adhered and a round bolt (6) is screwed to achieve compound reinforcement of the wooden beam (1). In the method, the bamboo board (2) is used as a reinforcing material, meanwhile the fiber cloth (3) is mechanically anchored, the bonding effect of the bamboo board (2), the fiber cloth (3) and the wooden beam (1) is strengthened through fusion of the round bolt (6) with the bamboo board (2) and the wooden beam (1), and the thickness of epoxy resin glue (4) between the bamboo board (2) and the wooden beam (1) is ensured by arranging the base layer (5) embedded with a solid filling (51). By the adoption of the method, the probability of untimely damage due to bonding layer failure in the wooden beam bending process is reduced, the wooden beam is reinforced by adopting two low-carbon environmentally friendly materials, respective advantages of the two materials are fully played, the bearing capability of the wooden beam is improved, and an original style and features of an old historic building structure restored as the old are achieved.

The invention discloses a pressing die and a method of a C-shaped wooden structural material with the high strength-weight ratio. The pressing die comprises a base, a core rod, clamps, pressurizing blocks, wedge blocks and pressure releasing blocks, wherein the base is of a groove-shaped structure with a U-shaped section, the base is composed of a bottom plate and side walls located on the two sides of the bottom plate, a groove is formed in the bottom plate, the groove is used for placing the core rod and the C-shaped wooden structural material, the core rod is used for wrapping the C-shapedwooden structural material around the outer wall of the core rod, the clamps are used for pressing C-shaped material flanges and curled edges of the C-shaped wooden structural material, a plurality ofpressurizing holes are formed in the joint between the left clamp and the right clamp, the pressurizing blocks are block bodies which are matched with the pressurizing holes and are detachably placedin the pressurizing holes, the two wedge blocks are arranged between the side wall of one of the two sides of the base and the left clamp and the side wall of the other one of the two sides of the base and the right clamp correspondingly, and the plurality of pressure releasing blocks are used for pressurized unloading of the wedge blocks and detaching the die. According to the pressing die and the method, the C-shaped wooden structural material with low cost can be quickly manufactured.

The invention discloses an external mounting type aviation electric pod. The external mounting type aviation electric pod comprises a pod core and a shell. The pod core is arranged in the shell. High-automation-degree operating design is adopted for the external mounting type aviation electric pod. All operation actions can be completed just through one pilot in a part-time job manner, and therefore the pod can be used for all aircraft with a single seat and multiple seats. Because no hydraulic and air compression systems are arranged, mechanical transmission parts are reduced by 80%, mechanical abrasion is greatly reduced, and the system is single and simplified; rolling of a winch and cable distributing and dragging winding and unwinding speed control precision can be improved, and therefore the fault rate is greatly decreased; and because a cable dragging automatic locking device is arranged, part of cable dragging force is transmitted to a pod body structure, loads on the winch are relieved, and using reliability is greatly improved. A more advanced thin-shell structure is adopted for a pod body, the ratio of strength to weight and the material utilizing rate are greatly increased.

The invention discloses a novel solid wood board and a processing method thereof, which comprises an upper board body and a lower board body which are uniformly and thinly cut from a board body, wherein the board body is composed of a plurality of boards with the same length and the same reference plane. The long regular octagonal prisms are arranged side by side and joined together to form; the bottom surfaces of the upper plate and the lower plate are hexagonal in shape, wherein the upper plate as the bottom layer is aligned with the lower plate as the top layer. After the sides are butted, they are pressed together, and a plurality of hollow structures are formed between the upper plate body and the lower plate body. The novel solid wood plank described in the present invention has a relatively stable plank structure, high strength-to-weight ratio, and the overall structure saves materials, so that the transportation cost is relatively low; and it has good heat insulation and sound insulation effects, less waste of leftover materials, and high wood utilization rate. high.

The invention provides an assembly type bamboo bridge. The assembly type bamboo bridge consists of bamboo longitudinal beams (1), bamboo transverse beams (2), bamboo panels (3), a transverse pre-stressing tendon (4) and a longitudinal pre-stressing tendon (16). All bamboos used by the assembly type bamboo bridge are soaked in a gum dipping tank which contains polyurethane resin and phenolic resin before being assembled, and boiled for 10-15 minutes at 100 DEG C-110 DEG C, wherein the volume ratio of the polyurethane resin to the phenolic resin is (2-2.5):1; and then, the bamboos are got out and dried, and a layer of waterborne polyurethane resin, a layer of polyurethane resin, a layer of waterborne polyurethane resin and a layer of resurcinolformaldehyde resin are uniformly coated on the outer surfaces of all bamboos in sequence. The assembly type bamboo bridge is large in structural strength, good in drawability, green and environment-friendly in used materials, standard in structural components, high in assembly degree, good in structural integrity, and capable of sufficiently bringing the advantages of the materials into play, and satisfying the normal use and durability needs of the bridge beam structure.

The invention discloses a method utilizing a two-step flat pressing process to produce hollow-core particleboards and composite boards. The method includes: producing single particleboards, and allowing each single particleboard to have a semicircular hole in a single face; coating modified polyvinyl acetate emulsion on a hollow-core face of each of two single particleboards, allowing the hollow-cores of the two single particleboards to be symmetrical, and then feeding the two signal particleboards into a cold pressing machine for cold pressing. By the method, the defects of direct flat pressing and extrusion methods are overcome, and the produced particleboards and composite boards are excellent in dynamic performance, low in formaldehyde emission, high in ratio of strength to weight and the like, can be used directly without applying veneers on surfaces, and is widely applicable to building and furniture industries. In addition, single-layer or multi-layer pressing machines are utilized, equipment cost is saved due to the fact that no new equipment needs to be purchased, and specific significance is provided for small and medium-sized artificial board enterprises.

The invention discloses a method for preparing hollow micro-nano carbon spheres by microwave assisted heating of lignin. Firstly, the lignin is placed in a microwave reactor, and then a carrier gas is passed through to remove the air therein; then the microwave reactor is turned on and kept loaded. The air flow rate is constant, and the temperature is raised to 350-550°C at a heating rate of 50-150°C / min, wherein the microwave power is 800-2000W; then the microwave power is adjusted to 300-800W, and the heating rate is 10-50°C / min. To 600-800°C, keep warm for 10-60 minutes; finally close the microwave reactor, keep the flow rate of the carrier gas constant, after cooling down to below 150°C, turn off the carrier gas, and the obtained solid product is hollow micro-nano carbon spheres. The invention will provide a new approach for high-value utilization of waste resource lignin, and is also expected to provide a new type of basic material for the field of carbon materials.