1、 Packaging and packaging requirements brief introduction packaging products are a train locomotive to export from China to South America.
2、 Packaging process and packaging forming process
2．1 Packaging molding will design the structural dimensions of the packing wooden box according to the equipment. The corresponding packaging materials will be selected and processed in a single piece according to the design requirements. For locomotive packaging, the base will be timely used with four sliding wood, two end logs, two long wood and base plate, column, diagonal brace, box plate and other components in the end plate of the separated side plate, and the beams, connecting beams, roof plates required by the top cover After processing and assembling, they are transported to the packaging workshop. Because the locomotive is very heavy, the substructure structure which only depends on the sliding wood and end wood is difficult to bear during lifting, so the steel wood composite structure is selected. The so-called steel wood composite structure is to set two 125px thick steel plates horizontally at the lifting position during loading and unloading. Each end of each steel plate is welded with a small vertical steel plate, and the small steel plate is equipped with lifting holes through steel cable. The middle of the two transverse steel plates are welded with several support blocks according to the bottom structure of the locomotive. Then four long sliding logs were fixed on two steel plates, and the cross-section size was 20cm × 24 cm. One end wood is fixed by bolts at both ends of sliding wood, and its cross-section size is 10 cm × 2ocm. Then, the board with width of 10 cm and thickness of 24 mm shall be nailed on the sliding wood as the base plate.
A long wood is fixed on the two long side edges of the base. Two long wood are located on the bottom plate, and the outer side and the bottom plate are flush. Their long end stops at the inside of the end wood, and just forms an outer frame with the end wood. The long wood is fixed by bolts, and the upper part is not all ordinary nuts, but the ring nut is used at intervals to provide a fastening place for the safety belt to be used. Similarly, ring nuts are used on the two intermediate bolts of the end logs. After that, the base is lifted and some narrow boards are nailed horizontally at a certain distance at the bottom of the sliding wood. The first is to prevent the bolt head extending out of the sliding wood from damaging the deck of the ship, etc., and the other is to further improve the overall strength of the base. Next, a bubble plastic film is laid on two transverse steel plate supports; then a layer of gas phase antirust film is laid on the whole floor; then on the anti rust film at the steel plate supporting locomotive, a layer of bubble plastic film is first laid, and then a plywood is placed on it, and several pieces of anti-skid rubber pad are placed on the adhesive board. Gas phase antirust film is a kind of special solid material mixed into plastic film. During storage and transportation, this kind of solid material will release a kind of gas molecule to cover the metal surface, form a protective layer, prevent the chemical reaction between oxygen and water and metal, and ensure that the mechanical and electrical equipment does not rust. It can also be heat sealed to block water vapor. Two layers of bubble plastic film can prevent the gas phase antirust film from damage of the steel frame and plywood below, which will affect the sealing and anti rust effect. Plywood can avoid the metal at the bottom of the locomotive and the steel frame on the base from hard hitting, causing damage or damage to the antirust film. The function of rubber pad is to increase friction coefficient, prevent locomotive from sliding and damage locomotive during transportation. The belt is fixed to the base with the belt and ring nut around the locomotive. The tension of the belt is 5kn. The movable accessories such as fire extinguishers in the car shall be fixed and a certain amount of desiccant bags shall be hung to prevent corrosion in the locomotive box. Finally, the above covered film and the gas phase antirust film are sealed and sealed, which can achieve better anti rust effect. Then wind loose gas phase antirust film with tape to minimize its volume and prevent other assembly accessories from scraping the film. The outer packing of locomotive adopts closed wooden box. The thick narrow board is used for the combination structure of frame wood and plywood. Each side is made up of 13 plywood of frame wood structure. Each component frame of the side plate is protruded left and right, which is convenient for the connection between small plywood. The whole side plate is nailed from the bottom to the top to half height, so as to facilitate the top cover installation. The top cover is a combination of four rectangular trees of 10 cm × 20 cm, which are bolted into two corner composite frame trees, and then the two frames are placed on both sides, and 18 beams distributed evenly are nailed on the top to form the frame structure of the top cover. The width of the frame is the width of the top cover, that is, the sum of the beam length and the width of the long wood. The top cover frame and 7 plywood used as top plates are hoisted to the top of locomotive by crane, and the top cover frame and column are nailed into one. Next, nail the side plate and the rest of the upper part of the end plate together, then nail all the top plates to the top cover frame together, and seal all the top cover together. So far, the whole locomotive packing box has been formed.
2.2 the packaging process of packaging auxiliary process also includes the following auxiliary processes. First, a layer of sun proof plastic film is laid on the top cover of the packing box, and the edge of the plastic film is about 2O cm lower than the upper part of the end plate and the side plate. The plastic film is fixed on the end plate and side plate of the wooden box with special tools. The film has excellent mechanical properties and is not easy to tear, and can play a good role in rain prevention. Then, the iron guard shall be nailed at the lifting position of upper edge and bottom edge of the packing box, and the marks for lifting shall be marked. Finally, the end plate side plate shall be printed with signs such as upward, moisture proof, center of gravity, package contract number, etc., and the product name, package size, weight, destination, etc. shall be indicated. The export transportation package of the locomotive is completed.
3、 The strength problem should be considered in the design and checking of wooden packing box. The steel plate used in locomotive packaging needs to bear the weight of the whole packing box and the impact force generated during lifting. Before that, the manufacturer has calculated and checked it according to the requirements. For ordinary wooden packing box, its calculation and checking calculation can be divided into base, end plate, side plate and top cover. The most important thing about the base is the skids. The number of skids is usually determined by the width of the packing box. German standard stipulates that two skids are used under 100 cm in width, and at least three skids must be used if the width is more than 180 cm, and the distance between each two skids shall not exceed 8O cm. The dimensions of the sliding and sleeper must be calculated, that is, the allowable bending strength shall be used to check whether the selected section size is enough to bear the external force during lifting. The shear strength and compressive strength of the sliding wood are often checked and calculated in Germany. This refers to the force of the sliding wood when the lower part of the sliding wood is subjected to the force from the chain cable upward, while the upper part of the sliding wood is under the pressure transmitted by the packing material through the sleeper. If the cross-section size and strength of the skid is not enough, the sliding wood will be damaged, which will affect the strength of the whole packing box. The results of calculation cannot exceed the allowable pressure strength, and the allowable experience value for pine is 0.2kn / cm2. In the same way, it can be checked whether the end face and side will break or collapse during stacking, and the pressure of the top cover when it is lifted horizontally by the chain cable or stacking.
