1. Purpose of this standard
To ensure the quality of the company cabinets products, to carry out quality control on the raw materials of the medium density fiberboard, this specification is specially formulated
2. The scope of application of this standard
It is suitable for the incoming inspection of melamine sheets for cabinets.
3. Reference Standard
GB/T 11718--1999 "Medium density fiberboard"
GB/T 18884--2002 "Home Kitchen Equipment"
4. Classification of medium density fiberboard:
4.1 Indoor type medium density fiberboard, suitable for dry environment.
4.2 Indoor moisture-proof medium-density fiberboard, suitable for humid environments.
4.3 outdoor mdf, suitable for outdoor use.
The general raw materials used in cabinets are indoor and indoor moisture-proof medium-density fiberboard.
5. Medium Density Fiberboard Terminology
5.1 Medium density fiberboard:
It uses wood fiber or other plant fibers as raw materials, and applies urea-formaldehyde resin or other synthetic resins. Under the piece, a sheet of pressed material. Other suitable additives can also be added to improve the characteristics of the board.
5.2 Indoor MDF:
Does not have a medium density fiberboard that is not subjected to short-term water immersion or high humidity.
5.3 Indoor moisture-proof medium density fiberboard:
Medium density fiberboard with short-term water immersion or high humidity.
5.4 Outdoor MDF:
Medium density fiberboard that can withstand the aging effect of climatic conditions, water immersion or the damp heat of water vapor in a ventilated place.
5.5 Local softness:
Local looseness caused by poor paving or poor bonding.
5.6 Corner defects:
Defects caused by damage to the four corners or edges of the board.
6 Inspection requirements
6.1 Appearance quality requirements and size requirements:
Note: Appearance quality inspection is under natural light or approximate natural light within the range of 300-600LX illuminance (for example, 40W fluorescent lamp), and the viewing distance is 700mm-1000mm. The inspection will be carried out by two people, and most of the same conclusions will be the inspection results.
Main inspectio--n items | skills requirement | Testing method | validation tools | ||
| 1 | Appe-arane qualit-y | Partiy soft | Not allowed | Sensory test | Visual inspection |
Cornr defect | Not allowed | Sensory test | Visual inspection | ||
| Oily | Not allowed | Sensory test | Visual inspection | ||
dark spots | Not allowed | Sensory test | Visual inspection | ||
Stratifi-d bubbli-g | Not allowed | Sensory test | Visual inspection | ||
| 2 | Thickness deviation | ±0. 20mm | Use a vernier caliper to meas-ure 8 points at the four corners 25 mm inward of the four sides of the board and 25 mm inward from the middle of the four sides of the board, and take the arithmetic average (note: the thickness of each measurement point in each board must not exceed its average土0.15mm) | calipers | |
| 3 | Length and width deviation | +5mm | Use a steel tape to measure the length on both sides of the board width, and measur-e the width on both sides of the board length, take the maximum value. | steel band tape | |
| 4 | Diagonal difference | ≤6 mm | Measure the length of the two diagonals of the board with a steel tape, and calculate the difference between the two diagonals | steel band tape | |
| 5 | Edge not straightness | ≤1.5mm/m | Align the side of the steel tape with the two corners on the same side of the board, use a straightedge to measure the maximum deviation between the side of the board and the steel tape, and measure all four sides of the board. | steel band tap Steel rulere | |
| 6 | Warpage (Warpage value) | 1、1m≤diagona ≤2m≤1 mm 2、2m<diagona ≤3 mm 3、diagona> 3m, ≤4 mm ≤3m | Place the MDF with the concave surface up on the horizontal surface, connect the two diagonal corners of the board with the sides of a steel tape (or thin steel wire rope), and use a steel ruler to measure the ratio of the maxi-mum chord height (warpage value) to the diagonal length That is the degree of warpage. | steel band tap Steel rulere | |
6.2 The supplier must provide the MDF physical and mechanical performance test report, including internal bonding strength, static bending strength, screw holding force, water absorption thickness expansion rate, moisture content, density, and the test results comply with GB/T11718-1999 indoor type, the requirements of the physical and mechanical properties of the board. It must also include the detection of free formaldehyde emission, and the test result meets the sanitation and environmental protection requirements specified in GB/T18884--- 2002, that is, the free formaldehyde emission of wood-based panels is ≤9mg/100g.
6.3 The company's other special requirements for MDF shall be indicated in the purchase contract.
7 Inspection rules
The company adopts sampling method for inspection of MDF
7.1 Appearance quality sampling rules
Batch range | Number of samples | Qualified number | Number of unqualified judgments | Sampl qualified number |
| 51-90 | 13 | 1 | 2 | 12 |
| 91-150 | 20 | 2 | 3 | 18 |
| 151-280 | 32 | 3 | 4 | 29 |
| 281-500 | 50 | 5 | 6 | 45 |
| 501-1200 | 80 | 7 | 8 | 73 |
| 1201-3200 | 125 | 10 | 11 | 115 |
| 3201-10000 | 200 | 14 | 15 | 186 |
| 10001-35000 | 315 | 21 | 22 | 294 |
7.2 Specification and size inspection rules
Batch range | Number of samples | Qualified number | Number of unqualified judgments | Sampl qualified number |
| 51-90 | 5 | 1 | 2 | 4 |
| 91-150 | 8 | 1 | 2 | 7 |
| 151-280 | 13 | 2 | 3 | 11 |
| 281-500 | 13 | 2 | 3 | 11 |
| 501-1200 | 20 | 3 | 4 | 17 |
| 1201-3200 | 32 | 5 | 6 | 27 |
| 3201-10000 | 32 | 5 | 6 | 27 |
| 10001-35000 | 50 | 7 | 8 | 43 |
7.3 The inspection of the physical and mechanical properties of MDF shall be subject to the inspection report provided by the supplier (for nail holding force and static bending strength performance, the quality inspector can check under the company’s existing conditions or based on experience). The physical and mechanical properties of wood-based panels are not up to standard and are responsible for the consequences that affect product quality.
7.4 For the special requirements specified in the purchase contract, the quality inspector shall inspect according to the contract.
7.5 Comprehensive judgment: 7.1, 7.2, 7.3, 7.4 are judged as qualified when all items meet the requirements.
8 Marking, packaging, transportation and storage
8.1 Marking
The product should be stamped with a mark indicating the type, grade, production date and inspector code.
8.2 Packaging
Products should be properly packaged according to different types, specifications and grades. Each package shall indicate the label of the manufacturer’s name, product name, trademark, specifications, number of grades and product standard number.
8.3 Transportation and storage
The product should be protected from moisture, rain, sun and deformation during transportation and storage.
Additional note: This standard is proposed by the Quality Department.