Views: 7 Author: Site Editor Publish Time: 2024-11-18 Origin: Site
In recent years, the soaring cost of packaging paper, coupled with the maturation of 3D mold printing technology, has provided pulp molding with another round of development opportunities.
This article addresses the current state of industrial packaging product design in the pulp molding industry and preliminarily proposes design specifications based on the unit structure of pulp molding products. These design specifications contribute to the standardization and normalization of pulp molding product design, and enhance the efficiency of pulp molding product design.
To standardize the design of pulp molding packaging padding, optimize product design, simplify the existing design process, and improve the packaging quality of China’s export products, this specification is formulated.
This specification applies to the design of pulp molding packaging padding for industrial products.
This specification is based on the database of typical structural unit of pulp molding products.
GB/T 453 Test method for tensile strength of paper and paperboard (constant rate of elongation method)
GB/T 453.1 Test method for thickness of paper and paperboard
GB/T 462 Test method for moisture content of paper and paperboard
GB/T 4857.1 Marking method for various parts of packaging and transport packages during testing
GB/T 4857.5 Drop test method for packaging and transport packages
GB/T 4857.7 Sinusoidal fixed-frequency vibration test method for packaging and transport packages
GB/T 4857.11 Horizontal impact test method for packaging and transport packages
GB 8168 Static compression test method for cushioning materials used in packaging
GB/T 10739 Standard atmospheric conditions for the treatment and testing of pulp, paper, and paperboard specimens
Wall Thickness: The average thickness of the side walls and supporting surfaces of pulp molding products.
Draft Angle: The angle between the side wall of the structural unit of the pulp molding product and its direction of demolding.
Cushioning Height: The minimum distance between the two load-bearing surfaces of the structural unit that bears the load.
Radius of Curvature: The radius of the curvature at the intersection of walls and at corners of the structural unit of pulp molding products.
Top and Bottom Padding Style: A packaging method that uses top and bottom surface padding when the packaged product is placed normally.
Front and Back Padding Style: A packaging method that uses front and back surface padding when the packaged product is placed normally.
Corner Padding Style: A packaging method that uses corner padding.
Overlap Padding Style: A packaging method that involves overlapping two or more pulp molding cushioning pads to form a single unit for packaging.
Positioning Dimensions: The size of the cushioning pad positioning module.
Supporting Area: The surface area of the cushioning pad that serves to bear the load and provide cushioning.
Requirements for Cushioning Pad Design
1. It must have good impact energy and vibration energy absorption to reduce the shock and vibration transmitted to the product.
2. It should disperse the stress acting on the product, protecting the product’s surface and protruding parts.
3. It should prevent the product from moving within the packaging container and from coming into contact with other products.
4. It must have good resistance to damage, environmental stability (stability in temperature and humidity), and physical compatibility (anti-static, etc.).
5. It should be recyclable and the waste should be easy to dispose of.
Product requirements
Product Dimensions:
The designed pulp molding products should not have significant dimensional deviations during the production process. The allowable range of dimensions for pulp molding products is as follows:
Dimensional Tolerance Range for Pulp Molding Products
Shape Dimensions (mm) Tolerance Range Length and Width ±2 Height ±1 Thickness ±0.2
Product appearance：
1. The surface of the product should be clean, dry, free of impurities, holes, damage, cracks, broken edges, stains, and other defects.
2. The front of heat-shaped products must not have cracks.
3. The front of paper products may have a mesh pattern, and the back may have slight wrinkles.
4. Products of the same batch should have uniform color and should not have obvious color differences.
5. The products should be odorless and must not be moldy.
Physical and Mechanical Properties of the Product:
The physical properties of the product refer to density, moisture content, thickness, etc., while mechanical properties refer to the material properties of the components of the paper-plastic products and the performance of the products.
Requirements for Physical and Mechanical Properties of the Product
Category Unit Performance Requirements Physical Properties Mass Deviation % ≤ ±5% Moisture Content % ≤ 14% Tensile Strength kN/m Tensile Strength ≥ 7 kN/m, Elongation ≥ 7% Elongation % Mechanical Properties Moisture Resistance Test % ≥ 50% Vibration Test The packaged item must not have functional damage, and the surface must be free of scratches. Drop Test When packaging electronic products, the product must not shed fibers. Compression Test The compression strength must be greater than the stacking strength, and the deformation amount must be ≤ 20mm.
All external factors that packaging items come into contact with during the circulation process are known as circulation environment factors. These factors are the main external causes of damage to packaging items. The environmental factors that affect the design of pulp molding cushioning pads can be mainly categorized into the following three types:
1. Physical and Mechanical Factors, which primarily refer to the impact and vibration during transportation, as well as stacking in storage and other external factors. Before designing pulp molding cushioning pads, it is advisable to fully understand the handling equipment, handling height, transportation methods and means during the transportation process, as well as the number of stacking layers in storage. Vibration can cause the surface fibers of the pulp molding cushioning pads to fall off and scratch the surface of the packaged products, and adjustments should be made based on the characteristics of different products.
2. Biochemical Factors, which include the influence of natural conditions such as temperature, humidity, rain, radiation, harmful gases, and microorganisms. Among these, humidity during transportation and storage has the greatest impact on pulp molding cushioning pads, posing a risk of the cushioning pads becoming damp and losing their effectiveness.
3. Human Factors, mainly referring to rough handling. The drop impact caused during the handling process is the most severe in terms of damaging packaging items and is a primary consideration.
The packaged product is the subject of study in the design of pulp molding products. Before conducting structural design, it is necessary to clarify the main properties related to the design, which include the shape, weight, size, fragility value, vulnerable parts, accessories, and their dimensions of the packaged product. Additionally, it is essential to understand the customer’s design requirements.
Depending on the production raw materials and their proportions, pulp molding materials mainly include five types: papermaking stock, waste corrugated cardboard, waste newspaper, paper trimmings, and a mixture of corrugated paper and newspaper. The performance of pulp molding materials depends on factors such as the raw material ratio, production process, and production equipment. Companies can obtain performance parameters by testing their own produced products.
Based on the nature of the packaged product and specific design requirements such as cost, select the appropriate pulp molding material.
1. For small and lightweight electronic products with low cushioning performance requirements and high appearance requirements, materials with softer properties such as waste newspaper and stock can be chosen.
2. For medium and heavy-duty or valuable electronic products with higher requirements for strength and cushioning performance, select mixed materials of corrugated paper and newspaper with different proportions based on the nature of the specific product.
Design of Pulp Molding Cushioning Pads
Development of Design Plans: In addition to fully understanding the circulation environment of the packaging items, the nature of the packaged products, and selecting appropriate pulp molding materials, it is also necessary to understand the customer’s design requirements and the size of the outer packaging box of the packaged products. Based on these factors, several feasible plans should be formulated.
1. Top and Bottom Padding Style. Limited by the outer packaging box, this packaging method has a smaller cushioning area and requires a high level of structural design, but the padding size is small, resulting in a lower production cost. For products with a larger width, it is possible to consider using the corner padding method on the top and bottom surfaces for packaging.
2. Front and Back Padding Style. Compared to the top and bottom padding style, the front and back padding style offers a larger protective area, with more structural design options and a lower design difficulty. However, the padding size is smaller, resulting in a higher production cost. For products with a smaller thickness, this packaging method approaches full coverage packaging.
3. Overlap Padding Style. This packaging form is based on the previous two styles and is suitable not only for products that require higher strength and cushioning but also for packaging where the distance between the product’s cushioning support surface and the inner surface of the outer packaging box is greater.
4. Combined Padding Style. For heavy or valuable electronic products, the use of pulp molding materials alone may not meet the cushioning design requirements. Additional corrugated cardboard structural components or honeycomb cardboard can be added as auxiliary materials. For the appearance protection of the packaged product, it is possible to consider fitting the product with a plastic film or corrugated cardboard structural components; to prevent the fibers of the pulp molding material from adhering to the product, it is advisable to fit the product with a plastic film.
● Information Source: Paper Packaging Industry, Packaging Zone
