MH
MINGHUNG
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I. What is Plywood? |
Plywood is an engineered wood panel made from thin layers of wood veneer (plies) glued together with the grain of adjacent layers oriented at right angles to each other. This cross-graining technique significantly enhances its strength, dimensional stability, and resistance to cracking, shrinking, and warping.
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II. Structure & Manufacturing Process |
1. Cross-Laminated Structure: Odd number of plies (3-ply, 5-ply, etc.) are arranged with perpendicular grain directions. This neutralizes wood's natural tendency to expand and contract.
2. Symmetry: The stack is symmetric around the central ply to prevent bending.
3. Manufacturing Steps: Log Debarking -> Peeling into Veneers -> Drying -> Gluing (Applying adhesive) -> Layering (Cross-graining) -> Hot Pressing (Curing the glue under heat and pressure) -> Finishing (Cooling, Sanding, Cutting, Grading).
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III. Classification & Types |
1. By Moisture Resistance (Bond Type - MOST IMPORTANT)
MR (Moisture Resistant) / Interior Grade: Uses Urea-Formaldehyde (UF) glue. Resistant to occasional humidity and condensation. Ideal for kitchen cabinet carcasses, furniture, and interior applications. Cannot withstand prolonged wetting.
WBP (Weather and Boil Proof) / Exterior Grade: Uses Phenol-Formaldehyde (PF) glue. Highly resistant to water, weather, and boiling. Suitable for outdoor use, concrete formwork, and areas with direct water exposure.
2. By Surface Finish
Sanded: Smooth surface for painting or veneering.
Natural Wood Veneer: Surface finished with a thin layer of precious wood (e.g., Oak, Walnut), offering a natural aesthetic for high-end furniture and cabinet doors.
Melamine Faced: Surface laminated with a durable, decorative paper (wood grain or solid colors). Water-resistant, scratch-resistant, and easy to clean. Perfect for kitchen cabinet interiors.
PVC Laminated: Provides superior waterproofing for bathrooms and labs.
3. By Wood Species
Hardwood Plywood: Eucalyptus, Okoume, Birch (very strong), Poplar. Denser and stronger, used for furniture.
Softwood Plywood: Pine, Fir, Spruce. Lighter weight, often used in construction.
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IV. Grading Standard |
Grades (A, B, C, D) denote the quality of the face and back veneers based on natural features and defects (knots, splits, patches).
First Letter: Face veneer grade.
Second Letter: Back veneer grade.
Example: BB/CC Grade means both faces are B grade, and the back is C grade. This is a cost-effective choice for cabinet boxes that will be covered or painted.
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V. Specifications |
Common Thicknesses: 3mm, 5mm, 9mm, 12mm, 15mm, 18mm (Cabinet Standard), 25mm.
Common Sizes: 1220mm x 2440mm (4' x 8') is the standard sheet size.
Emission Standards: E0 (≤0.5mg/L formaldehyde), E1 (≤1.5mg/L) are common indoor standards. Higher standards include CARB P2 (USA) and F★★★★ (Japan).
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VI. Advantages |
1. High Strength & Stability: Cross-graining provides excellent strength-to-weight ratio.
2. Large Sheets & Workability: Easy to cut, nail, and shape with common tools.
3. Cost-Effective: More uniform and often less expensive than solid wood.
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VII. Main Applications |
Interior Decoration: Ceilings, partitions, wall panels, floor underlayment.
Furniture Manufacturing: Cabinets, wardrobes, desks, beds, tables.
Construction: Concrete formwork, roof sheathing, subflooring.
Transportation: Vehicle and ship interiors.
Packaging: Export crates and pallets.
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Machinery Equipment |
The entire production line can be divided into several major sections: Log Handling, Veneer Peeling Preparation, Veneer Drying and Processing, Glue Application and Layup, Hot Pressing, and Finishing & Sanding.
Phase One: Log Handling Section
The purpose of this phase is to prepare raw logs into standard blocks suitable for peeling.
1. Log Debarker
Function: Removes the outer bark from the logs. Bark contains no fibers suitable for veneer, can wear down tools, and adversely affect glue bond quality.
Types: Ring debarkers, drum debarkers, etc.
2. Log Bucking Saw / Cross-Cut Saw
Function: Cuts long logs transversely into required-length blocks based on production plans and the presence of defects in the log. The length typically corresponds to the desired width of the plywood sheets (e.g., 1300mm, 2600mm).
3. Log Steaming Pond / Vat
Function: Subjects the log blocks to hydrothermal (steaming) treatment. This process softens the wood, increasing its plasticity and moisture content, which allows the blocks to be peeled into continuous, smooth, crack-free thin veneer sheets. This is a critical step for improving peel quality and yield.
Phase Two: Veneer Peeling Preparation Section
This is the core phase, transforming log blocks into thin veneer sheets.
4. Veneer Lathe
Function: One of the core machines of the production line. The prepared log block is mounted between two chucks and rotated at high speed. Simultaneously, a sharp peeling knife advances at a precise feed rate parallel to the axis of the block, peeling off a continuous sheet of veneer, much like a pencil sharpener.
Key Feature: Allows precise control of the veneer thickness (typically ranging from 0.1mm to 6mm or more).
5. Veneer Clipper
Function: Cuts the continuous ribbon of veneer into standardized sheets based on preset dimensions (length and width), removing defective sections (like splits, large knots) in the process, resulting in neat green (wet) veneer sheets.
Phase Three: Veneer Drying and Processing Section
Veneer exiting the lathe has a very high moisture content and must be dried.
6. Veneer Dryer
Function: Another core machine. Dries the veneer sheets by conveying them through a multi-level conveyor (mesh or roller) exposed to high-temperature hot air (typically provided by steam or thermal oil), rapidly reducing the moisture content from over 60% to the required process range of 8%-12%. Under-drying or over-drying negatively affects subsequent gluing quality.
7. Veneer Splicer
Function: Joins smaller dried veneer sheets or trimmed sheets into full-size sheets.
Types:
Tape Splicer: Uses paper or fiber tape applied to the back of the veneer to join sheets, primarily used for core layers.
Finger Joint Splicer: Mills finger joints into the edges of veneer sheets, applies glue, and presses them together. Creates a strong bond, can be used for face and back layers.
8. Veneer Patcher / Plugger
Function: Automatically repairs small defects in dried veneer sheets (e.g., small knots, holes). The machine routs out the defective area and automatically inserts a plug of healthy wood of the same shape, improving the veneer grade and material utilization.
Phase Four: Gluing and Layup Section
Applies glue to the veneer sheets and stacks them into panels.
9. Glue Spreader
Function: Applies adhesive (e.g., Urea-Formaldehyde UF, Phenol-Formaldehyde PF) evenly onto one or both sides of the veneer sheets via glue rollers. Glue spread amount can be precisely controlled, which is crucial for ensuring bond quality and managing production costs.
10. Layup Line / Assembly Line
Function: The glue-coated veneer sheets are stacked manually or automatically into a panel (mat) according to a predefined structure (number of piles, grain direction). Automated layup machines precisely align the layers, increasing production efficiency and layup quality.
Phase Five: Hot Pressing Section
This is the critical process where the laid-up mat is pressed into plywood.
11. Hot Press
Function: The heart of the production line, the most critical equipment. The assembled mats are loaded into a multi-opening hot press where they are subjected to predefined temperature, pressure, and time. The heat cures the glue, and the pressure bonds the veneer layers tightly together into a solid panel.
Key Parameters: Pressure, temperature, and time must be precisely controlled based on glue type, panel thickness, and number of layers.
Phase Six: Finishing Section
The pressed panels (known as rough panels) require processing to become finished products.
12. Cooling & Turning Rack
Function: Panels exiting the hot press are very hot. They need to be cooled to dissipate heat and moisture and relieve internal stresses to prevent warping. The turning rack separates the panels sheet by sheet to facilitate cooling.
13. Double-Edger Trimming Saw
Function: Saws off the four irregular, compacted edges of the cooled panels to create neat rectangular sheets with smooth edges.
14. Sander
Function: Key equipment determining the final surface quality. Sands the top and bottom surfaces of the panel using coarse and fine abrasive belts to eliminate thickness variation, pre-cured layers, and minor imperfections, resulting in a smooth, flat surface of uniform thickness suitable for further processing (like laminating or painting).
15. Inspection & Packaging Station
Function: Workers grade and inspect the finished panels, apply labels, and then bundle and package them using strapping machines for storage in the finished goods warehouse.
Summary Flowchart
Logs → Debarker → Bucking Saw → Steaming Vat → Veneer Lathe → Veneer Clipper → Veneer Dryer → (Patcher/Splicer) → Glue Spreader → Layup Station → Hot Press → Cooling Rack → Trimming Saw → Sander → Inspection & Packaging → Finished Product Storage
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Moisture-Proof Kitchen Plywood: Standard Sizes & Thickness |
I. Standard Thickness
Metric Thickness |
Imperial Thickness (Approx.) |
Primary Applications |
3mm, 4mm |
1/8", 5/32" |
Cabinet backs and drawer bottoms. For non-load-bearing areas. |
6mm, 9mm |
1/4", 3/8" |
Drawer bottoms, cabinet backing, decorative panels, or light shelving. |
12mm |
1/2" |
A versatile thickness for cabinet side panels, shelves, and drawer fronts. |
15mm |
5/8" |
For stronger carcass construction, longer shelves, vanities, and countertop substrates. |
18mm |
3/4" |
The industry standard for high-quality cabinet carcasses, load-bearing shelves, countertop substrates, and heavy-duty drawers. This is the most popular choice. |
25mm, 30mm+ |
1", 1-1/4" |
For heavy-duty countertops (e.g., kitchen islands), bar tops, and custom furniture requiring extreme support. |
Summary: For kitchen cabinet carcasses (main structure), 18mm is the most common and preferred standard thickness globally.
II. Standard Sizes
1. Standard Size (Most Common)
1220 mm × 2440 mm (Equivalent to 4 feet × 8 feet)
2. Other Common Sizes
1525 mm × 2440 mm (approx. 5' x 8')
1220 mm × 2745 mm (approx. 4' x 9')
1525 mm × 3050 mm (approx. 5' x 10')
3. Custom Sizes
Most manufacturers offer custom cutting services for non-standard lengths and widths, subject to MOQ and additional charges.
|
Moisture-Proof Kitchen Plywood Advantage |
1. Superior Moisture & Mold Resistance
Crafted with high-quality wood veneer cores and bonded with eco-friendly Moisture-Resistant (MR) glue, significantly reducing the risk of water penetration and mold growth.
Specially treated to effectively resist dampness and steam in kitchen and bathroom environments, preventing swelling, cracking, or deformation.
2. Stable & Durable Structure
Multi-layered cross-grained construction ensures even distribution of internal stress, providing high strength and dimensional stability.
Excellent load-bearing capacity, resistant to bending and warping, offering sturdy support for countertops and doors for long-lasting durability.
3. Eco-Friendly & Healthy
Complies with international environmental standards (such as E1/E0 grade), featuring very low formaldehyde emissions, creating a healthy and safe living space for you and your family.
Uses wood sources from sustainably managed forests, making it a green choice.
4. Smooth Surface & Easy Workability
The surface is flat and smooth with consistent thickness, making it ideal for secondary processing like laminating, painting, and edge banding.
Easy to cut, drill, and edge, suitable for various customized designs and fine woodworking, improving production efficiency.
✅ Transform Your Production Now!
Request Your Customized Quote & Technical Proposal:
Call +86 18769900191, +86 15805496117, +86 18954906501 or 【Live Chat】
Get a productivity upgrade plan within 24h
|
I. What is Plywood? |
Plywood is an engineered wood panel made from thin layers of wood veneer (plies) glued together with the grain of adjacent layers oriented at right angles to each other. This cross-graining technique significantly enhances its strength, dimensional stability, and resistance to cracking, shrinking, and warping.
|
II. Structure & Manufacturing Process |
1. Cross-Laminated Structure: Odd number of plies (3-ply, 5-ply, etc.) are arranged with perpendicular grain directions. This neutralizes wood's natural tendency to expand and contract.
2. Symmetry: The stack is symmetric around the central ply to prevent bending.
3. Manufacturing Steps: Log Debarking -> Peeling into Veneers -> Drying -> Gluing (Applying adhesive) -> Layering (Cross-graining) -> Hot Pressing (Curing the glue under heat and pressure) -> Finishing (Cooling, Sanding, Cutting, Grading).
|
III. Classification & Types |
1. By Moisture Resistance (Bond Type - MOST IMPORTANT)
MR (Moisture Resistant) / Interior Grade: Uses Urea-Formaldehyde (UF) glue. Resistant to occasional humidity and condensation. Ideal for kitchen cabinet carcasses, furniture, and interior applications. Cannot withstand prolonged wetting.
WBP (Weather and Boil Proof) / Exterior Grade: Uses Phenol-Formaldehyde (PF) glue. Highly resistant to water, weather, and boiling. Suitable for outdoor use, concrete formwork, and areas with direct water exposure.
2. By Surface Finish
Sanded: Smooth surface for painting or veneering.
Natural Wood Veneer: Surface finished with a thin layer of precious wood (e.g., Oak, Walnut), offering a natural aesthetic for high-end furniture and cabinet doors.
Melamine Faced: Surface laminated with a durable, decorative paper (wood grain or solid colors). Water-resistant, scratch-resistant, and easy to clean. Perfect for kitchen cabinet interiors.
PVC Laminated: Provides superior waterproofing for bathrooms and labs.
3. By Wood Species
Hardwood Plywood: Eucalyptus, Okoume, Birch (very strong), Poplar. Denser and stronger, used for furniture.
Softwood Plywood: Pine, Fir, Spruce. Lighter weight, often used in construction.
|
IV. Grading Standard |
Grades (A, B, C, D) denote the quality of the face and back veneers based on natural features and defects (knots, splits, patches).
First Letter: Face veneer grade.
Second Letter: Back veneer grade.
Example: BB/CC Grade means both faces are B grade, and the back is C grade. This is a cost-effective choice for cabinet boxes that will be covered or painted.
|
V. Specifications |
Common Thicknesses: 3mm, 5mm, 9mm, 12mm, 15mm, 18mm (Cabinet Standard), 25mm.
Common Sizes: 1220mm x 2440mm (4' x 8') is the standard sheet size.
Emission Standards: E0 (≤0.5mg/L formaldehyde), E1 (≤1.5mg/L) are common indoor standards. Higher standards include CARB P2 (USA) and F★★★★ (Japan).
|
VI. Advantages |
1. High Strength & Stability: Cross-graining provides excellent strength-to-weight ratio.
2. Large Sheets & Workability: Easy to cut, nail, and shape with common tools.
3. Cost-Effective: More uniform and often less expensive than solid wood.
|
VII. Main Applications |
Interior Decoration: Ceilings, partitions, wall panels, floor underlayment.
Furniture Manufacturing: Cabinets, wardrobes, desks, beds, tables.
Construction: Concrete formwork, roof sheathing, subflooring.
Transportation: Vehicle and ship interiors.
Packaging: Export crates and pallets.
|
Machinery Equipment |
The entire production line can be divided into several major sections: Log Handling, Veneer Peeling Preparation, Veneer Drying and Processing, Glue Application and Layup, Hot Pressing, and Finishing & Sanding.
Phase One: Log Handling Section
The purpose of this phase is to prepare raw logs into standard blocks suitable for peeling.
1. Log Debarker
Function: Removes the outer bark from the logs. Bark contains no fibers suitable for veneer, can wear down tools, and adversely affect glue bond quality.
Types: Ring debarkers, drum debarkers, etc.
2. Log Bucking Saw / Cross-Cut Saw
Function: Cuts long logs transversely into required-length blocks based on production plans and the presence of defects in the log. The length typically corresponds to the desired width of the plywood sheets (e.g., 1300mm, 2600mm).
3. Log Steaming Pond / Vat
Function: Subjects the log blocks to hydrothermal (steaming) treatment. This process softens the wood, increasing its plasticity and moisture content, which allows the blocks to be peeled into continuous, smooth, crack-free thin veneer sheets. This is a critical step for improving peel quality and yield.
Phase Two: Veneer Peeling Preparation Section
This is the core phase, transforming log blocks into thin veneer sheets.
4. Veneer Lathe
Function: One of the core machines of the production line. The prepared log block is mounted between two chucks and rotated at high speed. Simultaneously, a sharp peeling knife advances at a precise feed rate parallel to the axis of the block, peeling off a continuous sheet of veneer, much like a pencil sharpener.
Key Feature: Allows precise control of the veneer thickness (typically ranging from 0.1mm to 6mm or more).
5. Veneer Clipper
Function: Cuts the continuous ribbon of veneer into standardized sheets based on preset dimensions (length and width), removing defective sections (like splits, large knots) in the process, resulting in neat green (wet) veneer sheets.
Phase Three: Veneer Drying and Processing Section
Veneer exiting the lathe has a very high moisture content and must be dried.
6. Veneer Dryer
Function: Another core machine. Dries the veneer sheets by conveying them through a multi-level conveyor (mesh or roller) exposed to high-temperature hot air (typically provided by steam or thermal oil), rapidly reducing the moisture content from over 60% to the required process range of 8%-12%. Under-drying or over-drying negatively affects subsequent gluing quality.
7. Veneer Splicer
Function: Joins smaller dried veneer sheets or trimmed sheets into full-size sheets.
Types:
Tape Splicer: Uses paper or fiber tape applied to the back of the veneer to join sheets, primarily used for core layers.
Finger Joint Splicer: Mills finger joints into the edges of veneer sheets, applies glue, and presses them together. Creates a strong bond, can be used for face and back layers.
8. Veneer Patcher / Plugger
Function: Automatically repairs small defects in dried veneer sheets (e.g., small knots, holes). The machine routs out the defective area and automatically inserts a plug of healthy wood of the same shape, improving the veneer grade and material utilization.
Phase Four: Gluing and Layup Section
Applies glue to the veneer sheets and stacks them into panels.
9. Glue Spreader
Function: Applies adhesive (e.g., Urea-Formaldehyde UF, Phenol-Formaldehyde PF) evenly onto one or both sides of the veneer sheets via glue rollers. Glue spread amount can be precisely controlled, which is crucial for ensuring bond quality and managing production costs.
10. Layup Line / Assembly Line
Function: The glue-coated veneer sheets are stacked manually or automatically into a panel (mat) according to a predefined structure (number of piles, grain direction). Automated layup machines precisely align the layers, increasing production efficiency and layup quality.
Phase Five: Hot Pressing Section
This is the critical process where the laid-up mat is pressed into plywood.
11. Hot Press
Function: The heart of the production line, the most critical equipment. The assembled mats are loaded into a multi-opening hot press where they are subjected to predefined temperature, pressure, and time. The heat cures the glue, and the pressure bonds the veneer layers tightly together into a solid panel.
Key Parameters: Pressure, temperature, and time must be precisely controlled based on glue type, panel thickness, and number of layers.
Phase Six: Finishing Section
The pressed panels (known as rough panels) require processing to become finished products.
12. Cooling & Turning Rack
Function: Panels exiting the hot press are very hot. They need to be cooled to dissipate heat and moisture and relieve internal stresses to prevent warping. The turning rack separates the panels sheet by sheet to facilitate cooling.
13. Double-Edger Trimming Saw
Function: Saws off the four irregular, compacted edges of the cooled panels to create neat rectangular sheets with smooth edges.
14. Sander
Function: Key equipment determining the final surface quality. Sands the top and bottom surfaces of the panel using coarse and fine abrasive belts to eliminate thickness variation, pre-cured layers, and minor imperfections, resulting in a smooth, flat surface of uniform thickness suitable for further processing (like laminating or painting).
15. Inspection & Packaging Station
Function: Workers grade and inspect the finished panels, apply labels, and then bundle and package them using strapping machines for storage in the finished goods warehouse.
Summary Flowchart
Logs → Debarker → Bucking Saw → Steaming Vat → Veneer Lathe → Veneer Clipper → Veneer Dryer → (Patcher/Splicer) → Glue Spreader → Layup Station → Hot Press → Cooling Rack → Trimming Saw → Sander → Inspection & Packaging → Finished Product Storage
|
Moisture-Proof Kitchen Plywood: Standard Sizes & Thickness |
I. Standard Thickness
Metric Thickness |
Imperial Thickness (Approx.) |
Primary Applications |
3mm, 4mm |
1/8", 5/32" |
Cabinet backs and drawer bottoms. For non-load-bearing areas. |
6mm, 9mm |
1/4", 3/8" |
Drawer bottoms, cabinet backing, decorative panels, or light shelving. |
12mm |
1/2" |
A versatile thickness for cabinet side panels, shelves, and drawer fronts. |
15mm |
5/8" |
For stronger carcass construction, longer shelves, vanities, and countertop substrates. |
18mm |
3/4" |
The industry standard for high-quality cabinet carcasses, load-bearing shelves, countertop substrates, and heavy-duty drawers. This is the most popular choice. |
25mm, 30mm+ |
1", 1-1/4" |
For heavy-duty countertops (e.g., kitchen islands), bar tops, and custom furniture requiring extreme support. |
Summary: For kitchen cabinet carcasses (main structure), 18mm is the most common and preferred standard thickness globally.
II. Standard Sizes
1. Standard Size (Most Common)
1220 mm × 2440 mm (Equivalent to 4 feet × 8 feet)
2. Other Common Sizes
1525 mm × 2440 mm (approx. 5' x 8')
1220 mm × 2745 mm (approx. 4' x 9')
1525 mm × 3050 mm (approx. 5' x 10')
3. Custom Sizes
Most manufacturers offer custom cutting services for non-standard lengths and widths, subject to MOQ and additional charges.
|
Moisture-Proof Kitchen Plywood Advantage |
1. Superior Moisture & Mold Resistance
Crafted with high-quality wood veneer cores and bonded with eco-friendly Moisture-Resistant (MR) glue, significantly reducing the risk of water penetration and mold growth.
Specially treated to effectively resist dampness and steam in kitchen and bathroom environments, preventing swelling, cracking, or deformation.
2. Stable & Durable Structure
Multi-layered cross-grained construction ensures even distribution of internal stress, providing high strength and dimensional stability.
Excellent load-bearing capacity, resistant to bending and warping, offering sturdy support for countertops and doors for long-lasting durability.
3. Eco-Friendly & Healthy
Complies with international environmental standards (such as E1/E0 grade), featuring very low formaldehyde emissions, creating a healthy and safe living space for you and your family.
Uses wood sources from sustainably managed forests, making it a green choice.
4. Smooth Surface & Easy Workability
The surface is flat and smooth with consistent thickness, making it ideal for secondary processing like laminating, painting, and edge banding.
Easy to cut, drill, and edge, suitable for various customized designs and fine woodworking, improving production efficiency.
✅ Transform Your Production Now!
Request Your Customized Quote & Technical Proposal:
Call +86 18769900191, +86 15805496117, +86 18954906501 or 【Live Chat】
Get a productivity upgrade plan within 24h
