Inspection of wooden furniture
Competition in the furniture market is becoming increasingly fierce. "Customer satisfaction" has become the pursuit of furniture manufacturers. The importance of furniture quality inspection and control is obvious.
The inspection of furniture must consider many factors such as its function, appearance, safety, durability, materials, and environmental protection. It must not only meet people's requirements for product use value, but also meet people's needs for product aesthetics. From the perspective of customer needs, furniture products must not only pay attention to function and quality to ensure that the products purchased by consumers can be used normally within a certain period of time, but also meet people's requirements in shape, color, texture, etc.; and comply with human physiology, psychology and The rules of human body activities meet the requirements of safety, convenience, comfort and beauty. Now we will briefly explain the precautions for wooden furniture inspection from the aspects of functionality, appearance and safety.
1 Functions of Furniture
Furniture design and manufacturing are designed to serve people. Furniture products must meet people's needs and are the core of the product. That is to say, the furniture must achieve the use function and actively pursue the concept of "humanization".
1.1 Comfort
As household items, the design of furniture must be based on ergonomics to achieve the best match of the human-machine-environment system, which is the key to satisfying comfort. Basic requirements.
1.2 Durable
Products should meet physical and chemical performance requirements. The relevant physical and chemical properties mainly include: (1) Furniture can adapt to the climate environment where the product is used, especially the control of wood moisture content. The moisture content of solid wood furniture is generally 8% to 12%. (2) The mechanical properties of load-bearing parts meet relevant requirements. (3) The corrosion resistance of handles and other decorative hardware parts has passed the test. (4) The fabric meets relevant requirements, such as fireproof, waterproof, oilproof, antifouling, etc. (5) The rebound performance of back cushions and seat cushions.
1.3 Firmness
Fixed joints must be joined in a reliable way (Figure 1). Among them, the joining methods include: glue joining, tongue and groove joining, nail joining ("U" nails, gun nails, "S" nails, etc.), wood screw joining, and threaded joining. When joining, auxiliary backing is sometimes needed, such as triangular wood and connecting wood.
Mobile combination methods include loose-leaf, bumper beads, Ding clips, pull-out slide rails, etc. The mobile combination requires free movement and no noise. l.4 Sealing
The material splicing joints must be crack-proof, the splicing parts must be tightly joined, and the influence of the elasticity of the wood must be overcome (Figure 2). The following measures can be taken: (1) Add a straight process groove at the connection part, which is divided into "V" and "U" shapes. (2) The horizontal parts of the connection part are indented 1mm-3mm from the longitudinal parts, forming a step shape. (3) Large-format solid wood boards adopt edging and floating designs. (4) Rubber strips are embedded in the slots of large panels (such as door panels and bed panels). The pre-dyed width around the panels is greater than the depth of the slot, and the color is slightly lighter than the color plate.
Some parts of the product require light-shielding and dust-proof treatment. The doors of cabinets must be equipped with light-shielding strips; the bottom and middle layers of cabinet furniture must be equipped with dustproof boards to ensure that the inside of the door or drawers are clean.
1.5 Protection
Dressing cabinets, bedside tables, cupboards and other cabinets should have a velvet layer on the top and bottom of drawers to prevent damage to hard jewelry. The bottom of the upper building of stacked bookcases, dish racks, wardrobes, and combination racks must have flannel pads or similar materials to prevent damage to the lower building panels when moving. Paint residue and nails must be cleaned off the soles of the product to avoid damage to carpets and floors (Picture 3).
2 Appearance of Furniture
The entire set of furniture should be coordinated and balanced, and strive to have a unified style. Decoration techniques should conform to cultural tastes and artistic connotations; fancy decorations do not necessarily have to be gorgeous, and showing the beauty of natural forms can be beneficial. The artistry of furniture is mainly reflected in the shape, material, line type, decorative flowers, pillars, painting, etc.
2.1 Shape
Shape directly expresses the form of furniture and is greatly influenced by history and culture. Its choice directly affects the appearance and taste of the product.
2.2 Materials
Different tree species have different furniture styles, such as the simplicity of pine, the boldness of oak, the nobility and elegance of cherry wood, and the stability of birch. In order to save the amount of precious wood, furniture manufacturing widely uses veneer (wood slice) veneer technology. The basic requirements for veneer parquet veneer are: (1) The front of the product (such as panels, panels, door panels, etc.) must be made of high-quality veneer.
(2) The veneer texture and color of the entire set of products must be basically consistent and the effect must be natural. Wood textures can be divided into mountain grains, straight grains, random grains, tree burl grains, swirl grains, tiger stripes, bird's eye grains, water ripples, fish scale grains, rib grains, etc. (Figure 4). The texture of mountain grain veneer has a certain direction. The direction of panel wood texture is from left to right, and the direction of door panel wood texture is from bottom to top, so as to appear unified and smooth. (3) For veneers with a decorative surface width less than 175mm~250mm (such as large mountain grain), the large mountain grain should use the entire veneer and cannot be spliced ??in the width direction, and the mountain grain is required to be in the center in the width direction (called the center flower). (4) The patterns on the veneers of matching parts (such as doors) should be symmetrical. Cabinets with multiple drawers on the front (such as dressers and chests of drawers) should have continuous wood grain between drawers. (5) It is better if the tree bark has many knobs (or small living joints), the texture is distorted and irregular, and there are no missing joints.
2.3 Deviations in shape, position and structural size
The installation of furniture product parts should be symmetrical and uniform. (1) Cabinet products require a horizontal error of ±1.5mm after assembly, and a diagonal error of ±3mm. For spliced ??panels (such as flip tables, dining tables with KD middle plates, etc.), the flatness error is allowed to be within ±0.4mm. (2) Each unit part of modular furniture such as modular cabinets and audio cabinets must be smoothly connected, with continuous patterns and lines. The units of combined furniture use elbows, and the connecting parts have decorative blocks (or strips). (3) The joints of product parts must be firm and tight, with the front joint gap not exceeding 0.4mm and the side joint gap not exceeding 0.8mm. (4) The shelves of cabinets (or horizontal cabinets) must be level, with an error of 1.5 mm. (5) There must be a uniform pull-out gap between retractable drawers, doors and cabinets; the range is between 1.5mm-2.4mm (Figure 5).
2.4 Surface decoration treatment
The adhesion, corrosion resistance and wear resistance of the product surface paint and protective film meet relevant requirements.
Principles for surface treatment of furniture: (1) During daily use by consumers, the parts that come into contact with skin and clothing must be smooth, without debris, burrs, nails and other protrusions, and maintain good touch feel. (2) All parts that consumers may see must be painted to meet the basic requirements of visual beauty. (3) The painting effect is consistent with the overall appearance style (Figure 6), showing comfort, warmth, nobility, luxury or nostalgia. Its texture, tone, transparency, gloss and wood grain expression are consistent with the original color. The boards are consistent, and the texture of the precious wood veneer can be clearly displayed on the front (also called "transparent"). Many customers are afraid of reddish or greenish colors. (4) The three-dimensional shape of the carving and carving parts is obvious, the bottom of the shovel is smooth, the transition is smooth, and there are no obvious knife marks or excess wood filaments. The rough-cut pine wood carvings express a rich country atmosphere. (5) After various surface materials are painted, their texture, color tone, transparency, gloss, antique damage and wood grain should be unified and coordinated. There should be no obvious traces of artificial artifacts. Antique painting strives to be natural, with clear levels of light and dark, and smooth color transitions, and multi-tonal "painted faces" are not allowed.
2.5 Packaging labels
The function of packaging labels is to remind or guide consumers on how to assemble and use products, to facilitate product storage, circulation, sales and customer service. A good logo image can increase consumers' desire to purchase and reduce customer complaints. The appearance and packaging logo should be made as simple, clear and generous as possible to create a visual image of reliable quality and meticulous workmanship for consumers.
Packaging markings should be as follows: (1) There must be complete and correct marks on the outer box. Mark content usually includes: order number PO, product number ITEM, product trademark, product icon, product description, origin mark, quantity Q
T
Y, volume MEASURE, net weight N.W , gross weight G.W, handling and loading warning icons, production date, barcode and quality inspection batch number, etc. (2) Furniture labels, elevators, and maintenance instructions contain detailed usage precautions, including Chinese and English descriptions of materials, processes, structures, and styling design, as well as clear after-sales service content and consumer rights instructions. (3) The assembly diagram of the product should be clear and standardized, the assembly steps should be concise and easy to understand, and have instructions in Chinese and English. The assembled hardware accessories must be wrapped in a conspicuous colored (red or orange) plastic bag, and the colored plastic bag should be fixed on the rough parts of the product (such as the back panel, bed side panels, and the inside of the drawer surface). ), there should be no shaking or damage to avoid losing accessories and damaging the product surface.
(4) All single products must be labeled with product labels in hidden but accessible locations (such as the backboard of cabinets and the bottom of dining tables). Product label content: year, month and day of production, production factory, batch number, product number, place of origin, specific products also require additional barcodes, etc. 3 Safety of furniture and others
In the design and production of products, great attention must be paid to product safety. Eliminate the possibility of personal danger and damage to items during use.
3.1 Environmental protection requirements:
When furniture is used, volatile harmful gases such as free formaldehyde, benzene, and ammonia, as well as harmful substances such as heavy metals and radioactive rays, may be produced. Furniture has become one of the main sources of pollution in the indoor environment, among which free methane is the most prominent. my country's "Furniture Instructions for Use GB5296.6-2004" national mandatory standard clearly stipulates that the control indicators such as toxic and harmful substances in the materials and coatings used in furniture must be explained to consumers through packaging, hangtags, nameplates, labels, instructions, etc. be informed. The main sources of harmful substances in furniture are: wood preservatives, free benzene and lead in paint, free formaldehyde in rubber, and radioactive substances in some stones. In the production of furniture, green and environmentally friendly raw and auxiliary materials can be used; the artificial boards are faced and edge-sealed; special attention should be paid to sealing the back, bottom, top (dishboard) and other parts of the cabinet backboard that are easily overlooked with sealing paint.
3.2 Safety Requirements
All parts and components of furniture products must not crack or loosen during use (Figure 7).
The surface of the parts that consumers’ hands and bodies come into contact with must be smooth. The edges and corners of the product must be slightly chamfered or rounded, especially glass and mirrors, to avoid accidental injuries.
When designing products, it is not appropriate to have sharp shapes that protrude the whole when the height is less than 100mm. Pay special attention to coffee table products. There should be a load-bearing label on the glass shelf to ensure that it is used within the load-bearing range. Glass shelf packaging boxes and cartons must be printed with fragile signs. If there are nail types such as gun nails and code nails in the product package, instructions should be added to the assembly instructions.
When the bottom of the cabinet is extra wide (more than 700mm) or too long (more than 1750mm), add a supporting middle foot or similar structure. When the cabinet is extremely high, the rear frame must be reinforced with at least 3 pairs of triangular wood.
3.3 Requirements for protecting children’s safety
When inspecting furniture, you must consider whether it is safe for children to use.
For furniture with a height below 1000mm, dangerous materials such as ordinary glass should be used as much as possible. To prevent children from breaking the glass while playing and injuring others. Wooden doors or high-strength tempered glass are available.
Small parts such as round handles, hole plugs, wooden dowels, wheels, etc. are designed to be as strong as possible. If it is removable, instructions must be given for processing to prevent children from swallowing it.
3.5 Packaging safety test
Furniture packaging protects products from damage due to external effects (temperature, humidity, collision, static pressure, biological damage, etc.). In order to test the safety of the packaging The safety of the packaging must be tested. The testing standards include International Safe Transportation Association test standards 1A
& 1B (ISTA-Projec 1 A/B), 181 standards, etc. The test items are divided into pressure test, landing test, Vibration test and impact test, etc.