The global PVC foam board market is experiencing sustained double-digit annual growth, driven by a three-way material substitution megatrend: furniture manufacturers replacing solid wood and MDF with lighter, moisture-proof PVC foam panels; construction contractors replacing plywood and gypsum board with rot-proof, termite-resistant foam sheets for exterior cladding and interior partitions; and advertising/display producers replacing acrylic and aluminum composite panels with lower-cost, directly-printable foam boards. At the center of this shift is Celuka technology — the only continuous extrusion process that produces a board with dense, paint-ready solid skins on both surfaces and a lightweight closed-cell foam core in a single pass, eliminating the cost and labor of post-extrusion lamination.
The Chenxing SJSZ Series PVC/WPC Foam Board Extrusion Line is purpose-engineered to capture this demand. Covering board widths from 915mm to 1560mm across four extruder models (SJSZ51/105 through SJSZ92/188), the line produces the full portfolio of high-margin foam board products:
| Application | Board Type | Typical Thickness | Target Market |
|---|---|---|---|
| Kitchen & bathroom cabinet doors | Celuka PVC foam board | 15-18mm | Furniture manufacturing |
| Wardrobe & furniture panels | Celuka WPC foam board | 12-18mm | Interior decoration |
| Outdoor building cladding | Celuka PVC foam board | 10-20mm | Construction |
| Office partitions & room dividers | Celuka hollow-design board | 18-25mm | Commercial interiors |
| Advertising signs & exhibition displays | Celuka / free-foam board | 3-10mm | Printing & signage |
| Carbon crystal rock plate | Celuka high-density board | 8-15mm | Premium decoration |
| Building formwork (reusable) | Free-foam PVC board | 12-18mm | Construction |
The line supports both Celuka (skin) and free-foam processes through interchangeable die lip sets and configurable downstream equipment:
| Aspect | Celuka (Skin Foam) | Free-Foam |
|---|---|---|
| Skin layer | Solid skin 0.3-0.8mm both surfaces | No solid skin |
| Surface finish | Glossy, paint-ready, smooth | Matte, slightly textured |
| Board density (g/cm³) | 0.45-0.85 | 0.35-0.55 |
| Flexural modulus (MPa) | 2,000-2,800 | 1,200-1,800 |
| Screw holding (15mm board) | ≥800N | 400-600N |
| Die type | Celuka die with internal torpedo | Free-foam die (no torpedo) |
| Calibration | 4-pair setting table required | Guide rollers + cooling conveyor |
| Finished board selling price | 40-60% premium | Baseline |
| Best applications | Furniture, cabinets, cladding, signage | Insulation, packaging, formwork, void fillers |
Strategic insight: Many successful buyers start with a Celuka-configured line and add a free-foam die set as a low-cost product line extension. The Celuka line commands the higher-margin decorative/furniture market while the free-foam option captures volume construction and packaging business — all from the same extruder investment.
Carbon crystal rock plate represents a fast-growing premium segment within the PVC foam board market. By incorporating mineral fillers and carbon-based pigments into the Celuka formulation, manufacturers produce boards with stone-like texture, superior hardness (Shore D ≥70), and enhanced fire resistance — positioning them as direct competitors to engineered quartz and sintered stone in vanity tops, wall panels, and high-end interior decoration. The Chenxing line's precise temperature control and high-torque extrusion make it fully capable of processing these mineral-filled, higher-viscosity formulations.
The SJSZ Series is not limited to standard flat boards. With modular downstream tooling changes, the same extruder produces:
Solid cabinet door panels (15-18mm Celuka, direct hinge mounting, no edge banding required)
Furniture boards (12-18mm, screw-holding ≥800N, compatible with cam-lock assembly)
Advertising/printing boards (3-10mm Celuka, surface accepts UV flatbed, screen, and solvent printing)
Hollow-design partition panels (18-25mm with internal rib structure, 40% lighter than solid)
Building formwork panels (12-18mm free-foam, 50+ reuses, replacement for plywood formwork)
WPC wood-composite boards (15-35% wood flour, natural wood-like feel for furniture and interior decor)
The line's 1220mm standard width (4 feet) aligns with global sheet material handling standards, and finished boards at 2440mm length (8 feet) fit standard container loading with zero wasted space — reducing per-unit shipping cost by approximately 8-12% versus non-standard sizes.
Contact Nicole at +8615951187228 (WhatsApp/WeChat) or ceo@cxsljx.com for a tailored quotation with production estimates based on your target board specifications.
The SJSZ Series covers four extruder models matched to different board widths and production volumes. The SJSZ80/156 (1220mm, 350-400 kg/h) is the production-optimized configuration for standard 4ft board export markets, while the SJSZ92/188 (1560mm, 450-550 kg/h) serves high-volume producers targeting wide-format applications.
| Parameter | SJSZ51/105 | SJSZ65/132 | SJSZ80/156 | SJSZ92/188 |
|---|---|---|---|---|
| Screw Diameter (mm) | 51/105 | 65/132 | 80/156 | 92/188 |
| Screw Speed (r/min) | 1-38 | 1-37 | 1-37 | 1-35 |
| Main Motor (kW) | 18.5 | 37 | 75 | 110 |
| Barrel Heating (kW) | 22 | 35 | 55 | 75 |
| Output (kg/h) | 120-180 | 200-280 | 350-400 | 450-550 |
| Board Width (mm) | 915 | 1220 | 1220 | 1560 |
| Board Thickness (mm) | 3-12 | 3-18 | 5-20 | 8-30 |
| Foam Density (g/cm³) | 0.45-0.85 | 0.45-0.85 | 0.45-0.85 | 0.45-0.85 |
| Skin Density (g/cm³) | 1.3-1.4 | 1.3-1.4 | 1.3-1.4 | 1.3-1.4 |
| Haul-off Motor (kW) | 3.0 | 5.5 | 7.5 | 11.0 |
| Total Installed Power (kW) | ~60 | ~110 | ~180 | ~250 |
| Line Length (m) | 28-32 | 32-38 | 38-45 | 42-50 |
| Model | Recommended For | Typical Daily Output* | Investment Level |
|---|---|---|---|
| SJSZ51/105 | Startups, narrow board (915mm) for signage/packaging | ~3-4 tons | Entry |
| SJSZ65/132 | Small-medium factories, 1220mm boards, regional market | ~5-6 tons | Mid |
| SJSZ80/156 | Export-oriented standard 4ft board production | ~8-10 tons | Production |
| SJSZ92/188 | High-volume wide-format (1560mm) + thick board (up to 30mm) | ~11-13 tons | Industrial |
*Daily output at 24h continuous operation, 70% effective utilization, 12mm board density 0.6 g/cm³.
Screw geometry: Conical twin-screw design provides high shear and excellent plasticizing for PVC foam formulations. The 80/156 ratio (large feed end, small metering end) ensures stable melt pressure at the die.
Density range: Foam core density 0.45-0.85 g/cm³ is adjustable via foaming agent (AC) dosage and die temperature — lower density = lighter board + lower material cost; higher density = stronger board + better screw holding.
Skin density: The solid skin layer (1.3-1.4 g/cm³) is formed by the Celuka die's cooled torpedo, providing the structural strength for hinge/screw mounting.
Line length: Includes mixer, extruder, die, setting table, cooling bracket, cutting, and stacking — compact footprint for containerized factory setup.
Need help choosing the right model? Email ceo@cxsljx.com with your target board width, thickness, and daily output — Nicole will recommend the optimal configuration and provide a detailed quotation.
Every component in the Chenxing foam board line is spec'd for continuous 24/7 industrial production. The configurations below are based on the SJSZ80/156 1220mm model as the reference configuration. Smaller and larger models scale component dimensions proportionally.
The heart of the line — optimized specifically for PVC foam processing:
| Specification | SJSZ80/156 Value |
|---|---|
| Screw diameter | 80/156mm (metering/feed) |
| Screw speed range | 1-37 r/min |
| Effective barrel length | 1880mm |
| Screw material | 38CrMoAlA nitrided steel, surface hardness HV ≥840 |
| Barrel construction | Bimetallic liner (wear-resistant for AC foaming agent residue) |
| Main motor | Siemens Beide, 75kW |
| Speed control | ABB AC inverter |
| Temperature controller | Omron PID, multi-zone |
| Barrel heating | 55kW total, ceramic heater bands |
| Barrel cooling | Forced air, zoned |
| Screw temperature control | Oil-circulation internal cooling (prevents premature foaming inside barrel) |
| Vent zone | Vacuum pump, -0.06 MPa, removes moisture and volatiles |
| Gearbox | Hardened helical gear, NSK bearings |
| Output (1220×12mm board) | 350-400 kg/h |
Why conical twin-screw? PVC foam requires high compression ratio and controlled shear — the conical geometry naturally provides both. The large feed-end diameter accepts low-bulk-density dry blend powder, while the progressively decreasing diameter toward the metering zone builds the melt pressure needed for the Celuka die. Single-screw extruders cannot match this shear profile for PVC foam.
| Specification | Detail |
|---|---|
| Type | Screw volumetric feeder |
| Hopper | Stainless steel with bridge-breaking agitator |
| Drive | Variable speed, synchronized with extruder feed throat level sensor |
| Function | Delivers consistent PVC dry blend to extruder — prevents density variations caused by irregular feeding |
Inconsistent powder feed is the #1 cause of board density variation in foam extrusion. The bridge-breaking agitator prevents powder bridging and rat-holing in the hopper, while the level sensor feedback loop keeps the extruder feed throat at constant fill level.
| Unit | Specification |
|---|---|
| Hot mixer | SRL-Z 500/1000L, ABB inverter, 600-1200 rpm |
| Cooling mixer | SRL-W 1000/2000L, water-jacketed |
| Screw loader | Conveys cooled dry blend to extruder hopper |
Typical batch cycle for PVC Celuka foam formulation:
PVC resin (K-value 55-58) + CaCO₃ (5-15 phr) + Ca-Zn stabilizer (3-5 phr) + AC azodicarbonamide foaming agent (0.3-0.8 phr) + acrylic foam regulator (5-10 phr) + CPE impact modifier (4-8 phr) + TiO₂ (2-4 phr) + lubricants ↓ SRL-Z hot mixer: friction heating to 110-120°C ↓ Auto-discharge to SRL-W cooling mixer ↓ Cool to 40°C (below PVC glass transition, prevents agglomeration) ↓ Screw loader → extruder hopper
Batch capacity: 500-1000L per cycle, 8-12 batches/hour. The ABB inverter enables variable mixing speed — critical because the micro-dose foaming agent (0.3-0.8% by weight) must be uniformly dispersed across the entire batch. Inhomogeneous AC distribution causes surface pinholes and density variation in finished boards.
| Specification | Detail |
|---|---|
| Material | Superior alloy steel |
| Working width | 1220mm |
| Product thickness range | 5-20mm |
| Heating zones | 9 zones, 5kW each (45kW total) |
| Temperature control | Mold temperature controller (ambient to 160°C) |
| Die lip temperature | 150-175°C (PID per zone) |
| Internal structure | Celuka-type with adjustable torpedo/mandrel |
| Flow channels | Hard-chrome plated, mirror-polished |
| Die lip gap | Precision-ground, 0.01mm tolerance |
| Lip interchange | Interchangeable lip sets for thickness changes without full die swap |
| Skin thickness control | Torpedo position adjustable (closer to lip = thinner skin, further = thicker skin) |
How the Celuka die works: Melt enters and flows around the internal torpedo. The outer melt streams contact the cooled die lips (150-175°C), instantly forming a solid skin layer (0.3-0.8mm thick). The core melt — still containing undecomposed AC foaming agent — exits the die, where the 170-200°C temperature triggers AC decomposition (releasing N₂ gas), causing 2-3× expansion into closed-cell foam.
Free-foam die option: A free-foaming die head (no torpedo, wider lip opening) is also available for producing lower-density boards (0.35-0.55 g/cm³) without solid skin. Many buyers purchase both die sets — Celuka for premium decorative boards, free-foam for volume construction applications.
| Specification | Detail |
|---|---|
| Setting plates | 4 pairs (8 plates total) |
| Working width | 1400mm |
| Plate surface | Polished chrome-plated |
| Cooling method | Water-cooled, temperature-controlled by chiller |
| Temperature: 1st pair | 30-50°C (polished, for skin gloss and smoothness) |
| Temperature: 2nd-4th pair | 25-35°C (progressive cooling) |
| Plate gap adjustment | Precision lead screws, adjustable to final board thickness |
| Vacuum system | Vacuum slots in plates for board dimensional control |
| Longitudinal shift | 0.75kW gear motor drive for centering alignment |
| Mounting | On rails for die approach/retraction during startup |
The setting table's temperature profile is the most critical process variable in Celuka production. The first pair of plates must be warm enough (30-50°C) to maintain the skin surface gloss, but cool enough to set the skin — too cold cracks the skin, too hot allows foam blow-out through the skin. Subsequent pairs progressively cool the board to approximately 40°C before it exits to the cooling roller table.
| Specification | Detail |
|---|---|
| Length | 6 meters |
| Roller material | Stainless steel, surface hardened |
| Roller type | Transition rollers, adjustable pitch |
| Cooling method | Ambient + forced air |
| Integrated function | Houses lengthways cutting edge unit (blade edge trimmer) |
The 6m cooling roller table extends cooling time beyond the setting table to ensure complete core stabilization — the board center must cool below 40°C before cutting to prevent post-cut dimensional drift and stacking warpage. Stainless steel rollers prevent rust contamination on white/light-colored boards.
| Specification | Detail |
|---|---|
| Roller type | Rubber-covered |
| Roller dimensions | Φ25mm × 1420mm |
| Steel pipe wall thickness | 16mm |
| Rubber coating thickness | 17.5mm |
| Drive type | Helical tooth gear drive |
| Motor power | 7.5kW |
| Speed control | AC inverter, synchronized with extruder output |
| Nip pressure | Pneumatically adjustable |
Nip pressure control is critical for foam board: excessive pressure crushes the foam core, creating thickness reduction and density variation; insufficient pressure causes roller slippage, leading to inconsistent board speed and corrugation marks. The pneumatic system maintains constant, calibrated pressure throughout the production run.
| Stage | Equipment | Function | Precision |
|---|---|---|---|
| Stage 1 | Lengthways cutting edge machine (blade type) | Trims irregular board edges to final width | ±0.5mm |
| Stage 2 | Lengthways cutting machine (slitter) | Optional: splits wide board into multiple narrow panels | ±1mm |
| Stage 3 | Transverse cutting machine (flying saw) | Cuts board to final length (2440mm standard) | ±1mm |
Stage 1 (blade edge trimmer): Installed directly on the cooling bracket. Trims both board edges simultaneously. Edge strips are collected and recycled back to the mixer — closed-loop waste recovery reduces raw material cost by 2-3%.
Stage 2 (lengthways slitter): Optional. Splits a 1220mm wide board into e.g. 3 × 400mm or 4 × 300mm panels in a single pass. Blade spacing adjustable.
Stage 3 (flying saw): Saw carriage moves with the board during the cut cycle, synchronized via encoder with line speed. Cuts to preset length (standard 2440mm / 8ft). Dust collection cyclone for clean workshop air.
All three stages are PLC-synchronized. Length and width presets are stored in recipe memory for rapid product changeover.
| Specification | Detail |
|---|---|
| Type | Pneumatic tilting stacker |
| Collecting table length | 6 meters |
| Function | Automatic board counting and stacking |
| Stacking height | Adjustable |
| Discharge | Pallet-ready for forklift handling |
The stacker counts finished boards, stacks them on pallets, and signals when a pallet is full for forklift pickup. The pneumatic tilting mechanism ensures boards land flat without edge damage.
| Specification | Detail |
|---|---|
| Cooling capacity | 15-30 kW (model-dependent) |
| Supply temperature range | 15-30°C |
| Circulation | Closed-loop recirculation |
| Water quality | Deionized or soft water recommended |
| Function | Supplies temperature-controlled water to setting plates and calibration table |
Consistent water temperature is essential for Celuka skin quality — temperature fluctuations of as little as ±3°C cause visible surface gloss variation across the board. The closed-loop chiller maintains ±1°C stability, eliminating the most common cause of surface defects in foam board production.
Seven engineering advantages that differentiate the Chenxing SJSZ Series from commodity extrusion equipment. Each feature addresses a specific Celuka foam board production challenge.
The Celuka process creates a PVC foam board with dense, smooth solid skins (0.3-0.8mm, density 1.3-1.4 g/cm³) on both surfaces and a closed-cell foamed core (density 0.45-0.85 g/cm³) in a single continuous extrusion. The die's internal torpedo forces melt against cooled die lips, instantly forming the skin layer while the core — containing AC azodicarbonamide foaming agent — expands upon exiting the die.
Measurable benefits versus laminated or post-surfaced boards:
| Property | Celuka Single-Pass | Post-Laminated Board |
|---|---|---|
| Surface finish | Paint-ready, glossy | Requires sanding + primer |
| Production steps | 1 (extrusion only) | 3+ (extrude + sand + laminate) |
| Skin adhesion | Molecular bond (same material) | Adhesive bond (delamination risk) |
| Weight vs solid PVC | 30-50% lighter | Same or heavier |
| Thermal insulation (λ) | 0.04-0.07 W/m·K | ~0.17 W/m·K (solid) |
| Screw holding (15mm) | ≥800N | 600-800N (laminate dependent) |
No lamination, no secondary surfacing, no adhesive curing time — the board is ready for CNC routing, hinge mounting, and UV printing directly off the stacker.
At the core of the line: a 75kW Siemens Beide motor driving a 38CrMoAlA nitrided conical twin-screw pair through an ABB inverter and Omron PID temperature controller.
| Engineering Detail | Why It Matters |
|---|---|
| Screw nitriding to HV ≥840 | Resists abrasive wear from CaCO₃ filler and AC foaming agent decomposition residue |
| Bimetallic barrel liner | Extended service life with corrosive foaming formulations |
| Oil-circulation screw core cooling | Prevents premature foaming inside the barrel — AC decomposes at 170-200°C, barrel zones must stay below this |
| Vent zone with -0.06 MPa vacuum | Removes moisture and volatiles that cause surface defects and core voids |
| Screw speed 1-37 r/min | Broad operating window: slow for thick/heavy boards, fast for thin/light boards |
| Effective barrel length 1880mm | Long residence time for complete PVC gelation before die entry |
Proven daily output (1220×12mm board, density 0.6 g/cm³): At 350-400 kg/h, the line produces 16-19 boards/hour (1220×2440mm), equivalent to approximately 380-450 boards per 24 hours (~8.2-9.7 metric tons daily at 70% effective utilization).
The die is where Celuka board quality is made or lost. Chenxing's 1220mm wide superior alloy steel die features 9 independent heating zones (5kW each, 45kW total), each with its own PID loop — ensuring melt temperature uniformity within ±2°C across the full 1220mm width.
Die engineering specifications:
Material: Superior alloy steel, heat-treated, with hard-chrome plated and mirror-polished internal flow channels for minimal melt residence and easy purging during color/formulation changes
Die lip gap: Precision-ground to 0.01mm tolerance — uneven lip gap causes thickness variation and board curvature
Mold temperature controller: Ambient to 160°C range, maintains die lip at 150-175°C (the optimal window for skin formation without AC pre-decomposition)
Interchangeable lip sets: Switch between 5-20mm thickness range without removing the die from the extruder — reduces changeover time from hours to under 30 minutes
Adjustable torpedo position: Controls skin thickness: closer to lip = thinner skin (0.3mm) for printing boards, further = thicker skin (0.8mm) for furniture panels requiring maximum screw holding
Free-foam lip set: Available separately — converts the same extruder to free-foam production in one shift
The setting table performs two functions simultaneously: calibrates the board to final thickness with ±0.1mm precision, and sets the Celuka skin surface to a glossy, defect-free finish.
The graduated cooling profile:
| Plate Pair | Temperature | Function |
|---|---|---|
| 1st pair | 30-50°C | Sets skin gloss, prevents cracking |
| 2nd pair | 28-35°C | Sets board thickness, draws vacuum |
| 3rd pair | 25-32°C | Continues cooling, maintains flatness |
| 4th pair | 25-30°C | Final calibration, board exits at ~40°C |
The 1st pair's polished chrome-plated surface at 30-50°C is the critical process window: hot enough to keep the PVC skin surface above its glass transition temperature (permitting flow and gloss development), but cool enough to prevent the foaming core from blowing through the skin. This balance is what separates Celuka-quality boards from commodity foam sheets with visible surface defects.
Additional calibration features:
Vacuum slots in all plates draw the board firmly against the plate surface for consistent thickness
Precision lead screws adjust plate gap — calibrated once during setup, then locked
0.75kW gear motor provides longitudinal shift for centering the board between plates
Entire table rides on rails for quick die approach during startup and retraction for die cleaning
After the setting table, the board enters a 6-meter stainless steel roller conveyor for final cooling and edge finishing.
Why 6 meters matters: Foam board's insulating core retains heat long after the skins have set. If the board center exceeds 40°C when it reaches the cutting saw, it will continue expanding and contracting after cutting, causing ±2-3mm length variation and stacking warpage. The 6m cooling table provides sufficient residence time (approximately 60-90 seconds at 4-6 m/min line speed) for core temperature to stabilize below 40°C with ambient and forced-air cooling.
Integrated edge trimming: The blade-type lengthways cutting edge machine is mounted directly on the cooling bracket. It trims both irregular board edges to exact width (adjustable for 915-1220mm range) before the board reaches the cutting saw. Trimmed edge strips are collected via a vacuum system and returned to the mixer — a closed-loop recycling system that recovers 2-3% of raw material cost.
The stainless steel rollers are surface-hardened to prevent wear grooves that could mark board surfaces, and are mounted on adjustable pitch to support different board widths without allowing unsupported board sections to sag.
Boards exit the cooling table and enter a three-stage, PLC-synchronized cutting system:
Cooling Table → [Stage 1: Edge Trimmer] → [Stage 2: Slitter (optional)] → [Stage 3: Flying Saw] → Stacker
| Stage | Equipment | Function | Tolerance |
|---|---|---|---|
| 1 | Blade edge trimmer | Trims both edges to final width (1220mm) | ±0.5mm |
| 2 | Lengthways slitter | Splits wide board into narrow panels (optional) | ±1.0mm |
| 3 | Transverse flying saw | Cuts to final length (2440mm standard) | ±1.0mm |
Stage 2 flexibility: The lengthways slitter is optional equipment. When activated, it splits the 1220mm board into e.g. 3 × 400mm or 4 × 300mm panels — allowing one production run to serve multiple product SKUs. Blade spacing is adjustable, and the slitter can be bypassed entirely for full-width board production.
Stage 3 flying saw precision: The saw carriage uses an encoder to match line speed during the cut cycle, then rapidly returns to the start position. This "flying cut" mechanism eliminates the need to stop the line for each cut — critical for foam board, where stopping/starting causes visible transverse lines on the board surface. Built-in dust collection cyclone captures cutting debris for workshop cleanliness.
Recipe memory stores length and slitter presets for rapid product changeover: operator selects a recipe from the HMI, and all three stages automatically configure.
Foam board quality begins in the mixer. The SRL-Z hot mixer with ABB inverter drive provides variable mixing speed (600-1200 rpm) — enabling optimized shear for each formulation.
Why the mixer matters for foam board:
The AC azodicarbonamide foaming agent is dosed at only 0.3-0.8% by weight — meaning if the mixer cannot uniformly disperse this micro-dose across a 500-1000L batch, some boards will over-foam (large core voids, low density) while others under-foam (dense, heavy, high cost). Surface pinholes — the most common foam board defect — are almost always traced to uneven AC dispersion in the dry blend.
The automated batch cycle:
Step 1: Load PVC resin + CaCO₃ + stabilizer + processing aids into SRL-Z Step 2: ABB inverter ramps mixing speed 600→1200 rpm Step 3: Friction heating brings batch to 110-120°C (timed, not sensed — for consistency) Step 4: Auto-discharge gate opens → material drops to SRL-W cooling mixer Step 5: SRL-W water-jacketed mixer cools batch to 40°C Step 6: Screw loader conveys cooled dry blend to extruder hopper
Batch capacity 500-1000L, 8-12 batches per hour. The entire cycle is PLC-automated — operator loads raw materials, presses start, and the system handles heating, timing, discharge, cooling, and conveying to the extruder.
The Chenxing SJSZ Series supports two distinct production routes — Celuka skinning and free-foaming — through interchangeable die sets and configurable downstream equipment. Below are both complete workflows with process parameters.
This is the primary production route for premium decorative and structural boards. The Celuka process achieves a paint-ready surface with Shore D ≥65 hardness in a single continuous pass.
Standard PVC Celuka foam formulation (parts per hundred resin, phr):
| Ingredient | phr | Function |
|---|---|---|
| PVC resin (K-value 55-58) | 100 | Base polymer — lower K-value for better foamability |
| CaCO₃ filler | 5-15 | Cost reduction, rigidity, nucleation sites for foam cells |
| Ca-Zn stabilizer | 3-5 | Thermal stabilization, prevents PVC degradation at processing temperatures |
| AC azodicarbonamide foaming agent | 0.3-0.8 | Gas source — decomposes at 170-200°C, releasing N₂ |
| Acrylic foam regulator | 5-10 | Controls melt strength — prevents cell coalescence and foam collapse |
| CPE impact modifier | 4-8 | Impact resistance, especially for furniture applications |
| TiO₂ | 2-4 | Whiteness, UV resistance for outdoor applications |
| Lubricants (internal + external) | 1-3 | Melt flow control, metal release |
Mixing sequence (SRL-Z hot mixer → SRL-W cooling mixer):
Load PVC resin + stabilizer + lubricants → mix at low speed (600 rpm) for 1 minute
Add CaCO₃ + TiO₂ → increase to 1000 rpm, mix until 80°C
Add impact modifier + foam regulator → continue mixing
At 105°C, add AC foaming agent (added late to prevent premature decomposition)
Continue mixing to 110-120°C → auto-discharge to cooling mixer
SRL-W cooling mixer: cool to 40°C under agitation → discharge
Screw loader conveys cooled dry blend to extruder hopper
Critical control point: AC foaming agent must not exceed 120°C in the mixer. Premature decomposition in the mixer (not the die) produces gas that escapes before the melt forms — resulting in boards that fail to foam to target density.
Dry blend enters the SJSZ80/156 conical twin-screw extruder via the powder feeder. The screw progressively compresses, shears, and plasticizes the material through five barrel zones:
| Barrel Zone | Temperature (°C) | Function |
|---|---|---|
| Zone 1 (feed) | 150 | Preheating, initial compaction |
| Zone 2 (compression) | 165 | PVC gelation begins |
| Zone 3 (metering 1) | 175 | Full plasticizing, maximum shear |
| Zone 4 (metering 2) | 170 | Homogenization |
| Zone 5 (die end) | 165 | Slight cooling — prevents premature AC decomposition |
Additional extrusion parameters:
Screw oil circulation temperature: 140-150°C
Vent vacuum: -0.06 MPa
Melt temperature at die entry: 165-175°C
Melt pressure at die entry: 15-25 MPa
The slightly cooler Zone 5 is deliberate — it ensures the melt enters the die below AC decomposition temperature (170°C), so foaming occurs only after the skin has formed at the die lips.
The melt enters the Celuka die at 165-175°C and flows around the internal torpedo:
Outer melt streams contact the cooled die lips (150-160°C, maintained by mold temperature controller) — instantly solidifying into a 0.3-0.8mm skin on both surfaces
Core melt, still at 165-175°C with undecomposed AC, exits the die lips
Upon exiting, the core temperature reaches 170-200°C (from residual heat + shear heating), triggering AC decomposition
AC decomposes: H₂N-CO-N=N-CO-NH₂ → N₂↑ + CO↑ + NH₃↑ + solid residue
Released gases expand the core 2-3× the die lip opening, forming closed-cell foam structure
Board thickness jumps from die lip gap to final calibrated thickness as it enters the setting table
Skin thickness control: Torpedo position determines skin thickness — closer to lip reduces skin (0.3mm for printing boards), further from lip increases skin (0.8mm for furniture panels with high screw-holding requirements).
The expanded foam board immediately enters the 4-pair setting table (1400mm wide, water-cooled, polished chrome-plated plates):
| Plate Pair | Temperature | Function | Process Window Risk |
|---|---|---|---|
| 1st | 30-50°C | Sets skin gloss, prevents cracking | Too cold → skin cracks. Too hot → foam blows through skin |
| 2nd | 28-35°C | Calibrates thickness, vacuum on | Insufficient vacuum → thickness variation |
| 3rd | 25-32°C | Progressive cooling, maintains flatness | Uneven cooling → board curvature |
| 4th | 25-30°C | Final calibration | — |
Vacuum slots in each plate pair draw the board firmly against the plate surfaces, ensuring thickness precision of ±0.1mm. Board exits the setting table at approximately 40°C.
The board travels through the 6-meter stainless steel cooling roller table:
Ambient + forced air progressively cools the board to approximately 25°C
At approximately 3-4 meters along the table, the blade edge trimmer removes irregular board edges
Edge strips are collected and returned to the mixer for recycling
Final board width: 1220mm ±1mm
The 6-meter length provides 60-90 seconds of additional cooling at typical line speeds (4-6 m/min) — sufficient for the foam core center to stabilize below 40°C before cutting.
The cooled board enters the three-stage cutting system:
Transverse flying saw: Cuts board to 2440mm length (±1mm), synchronized with line speed via encoder
Optional lengthways slitter: Splits wide board into multiple narrow panels if required
Automatic stacker: Pneumatic tilting stacker counts and stacks finished boards on pallets
Quality control checkpoint (per batch sampling):
| Parameter | Standard | Test Method |
|---|---|---|
| Density | 0.45-0.85 g/cm³ (as specified) | ASTM D792 |
| Surface hardness | Shore D ≥65 | ASTM D2240 |
| Screw pull-out force | ≥800N (15mm board) | BS EN 320 equivalent |
| Dimensional (L×W) | ±1mm | Calibrated tape/caliper |
| Thickness | ±0.1mm | Micrometer |
| Flatness | ≤2mm/m | Straight edge + feeler gauge |
| Surface appearance | No pinholes, bubbles, color streaks | Visual inspection |
Finished pallets are wrapped in PE film for warehouse storage or container loading.
The free-foaming route uses the same extruder but with a different die set and simplified downstream equipment. It produces lower-density, lower-cost boards for non-decorative applications.
Key differences from Celuka route:
| Aspect | Celuka Route | Free-Foam Route |
|---|---|---|
| Die type | Celuka die with internal torpedo | Free-foam die (no torpedo) — wider lip opening |
| Skin formation | Solid skin 0.3-0.8mm via cooled die lips | No skin — board foams freely in all directions |
| Foam expansion | Controlled (core only) — 2-3× | Free in all directions — 3-5× |
| Achievable density | 0.45-0.85 g/cm³ | 0.35-0.55 g/cm³ |
| Surface finish | Glossy, smooth, paint-ready | Matte, slightly textured |
| Downstream | Setting table (4-pair) required | Simple guide rollers + extended cooling conveyor |
| Post-processing | None | Optional sanding/planing for smooth finish |
| Formulation differences | Higher foam regulator (5-10 phr) for melt strength | Lower foam regulator, higher AC (0.5-1.0 phr) |
Free-foam process steps (simplified):
Formulation: Same mixing process, adjusted AC dosage (0.5-1.0 phr vs 0.3-0.8)
Extrusion: Same SJSZ80/156, barrel temperatures 5-10°C higher to promote rapid foaming at die exit
Free-foam die: No torpedo — melt exits die and foams freely, expansion 3-5× die gap
Guide rollers + cooling: Board passes through guide rollers (not setting plates) on extended cooling conveyor — 10-12 meters for adequate cooling without calibration constraint
Optional sanding: For applications requiring smooth surface, a post-extrusion sanding/planing station is added
Cutting & stacking: Same three-stage cutting system
Typical free-foam applications:
Construction formwork panels (50+ reuses vs 5-8 for plywood)
Thermal insulation boards (λ = 0.04-0.06 W/m·K)
Protective packaging sheets
Non-visible structural cores for sandwich panels
Void fillers and spacers in construction
Production flexibility: Buyers who start with a Celuka configuration can add a free-foam die set and extended cooling conveyor later — converting the line to free-foam production in one shift. This dual-capability approach de-risks the investment by providing access to both premium (Celuka) and volume (free-foam) market segments from the same extruder.
Celuka foam board features a solid, dense skin layer (0.3-0.8mm, density 1.3-1.4 g/cm³) on both surfaces with a foamed core (0.45-0.85 g/cm³). The skin provides a glossy, paint-ready surface that requires no post-processing — ideal for furniture panels, kitchen cabinet doors, bathroom partitions, advertising signs, and building formwork where surface aesthetics and screw-holding strength (≥800N for 15mm board) are critical. Free-foam board has no solid skin, producing a matte, textured surface at lower density (0.35-0.55 g/cm³) and lower cost. It suits thermal insulation, packaging, and non-visible structural applications. The Celuka-configured line costs approximately 20-30% more due to the complex die and setting table, but Celuka boards command 40-60% higher market prices. Many buyers start with a Celuka line and later add a free-foam die set for product diversification — the extruder remains the same; only the die and downstream setup change.
The SJSZ80/156 model produces standard 1220mm × 2440mm boards (4ft × 8ft) in thicknesses from 5-20mm. The SJSZ51/105 supports 915mm width (3-12mm), and the SJSZ92/188 extends to 1560mm width (8-30mm). For a 1220×2440×12mm board at density 0.6 g/cm³, board weight is approximately 21.5 kg. At the SJSZ80/156's rated 350-400 kg/h output: 16-19 boards per hour, approximately 380-450 boards per 24 hours, yielding 8.2-9.7 metric tons daily. For thicker 18mm boards: 11-13 boards per hour. Maximum practical daily output is ultimately limited by cooling capacity — the board center must cool below 40°C before stacking to prevent post-stack warping. The 6-meter cooling table plus ambient cooling is sufficient for up to 20mm boards at rated output. Beyond 20mm, line speed is reduced to allow additional cooling time.
WPC foam board incorporates wood flour (60-120 mesh, 15-35% by weight) into the PVC matrix, requiring six key formulation and process adjustments. (a) Wood flour must be pre-dried to moisture ≤1% at 100-110°C for 2-4 hours using a separate dryer — moisture exceeding 1% vaporizes during extrusion, causing surface blisters and core voids. (b) Increase AC foaming agent to 0.5-1.2 phr (versus 0.3-0.8 for pure PVC) because wood flour absorbs heat and suppresses AC decomposition. (c) Add coupling agent MAPE (maleic anhydride polyethylene) at 2-4% of wood flour weight for PVC-wood interfacial bonding — without it, flexural strength drops 30-40%. (d) Increase acrylic processing aid by 2-3 phr to compensate for higher melt viscosity from wood flour. (e) Reduce screw temperature by 5-10°C (maximum 180°C at die) to prevent wood charring. (f) Expect output at approximately 80-85% of pure PVC foam rate due to higher viscosity. WPC boards offer a more natural wood-like feel and superior screw holding, making them popular in furniture and interior decoration markets.
Export-grade PVC Celuka foam board is tested against the following parameters, verified by third-party reports (SGS/TUV) with each shipment. Density: 0.45-0.85 g/cm³ per product specification, measured by ASTM D792 water displacement method. Surface hardness: Shore D ≥65 for Celuka skin board (ASTM D2240). Screw pull-out force: ≥800N for 15mm thick board (BS EN 320 equivalent) — this is the critical parameter for furniture applications where hinges and handles are screwed directly into the board. Flexural strength: ≥18 MPa, flexural modulus ≥1800 MPa (ASTM D790 three-point bending). Flatness: ≤2mm deviation per meter length, measured with straight edge and feeler gauge — warping exceeding 2mm/m indicates insufficient cooling or residual internal stress from non-uniform foaming. Water absorption: ≤1.0% after 24-hour immersion (ASTM D570). Vicat softening temperature: ≥75°C (ASTM D1525). Fire rating: B1 or B2 classification (DIN 4102 / EN 13501-1), formulation-dependent with flame retardant additives. All test reports are provided.
The SJSZ80/156 complete line — including high-speed mixer, cooling mixer, screw loader, powder feeder, extruder, Celuka die, 4-pair setting table, 6m cooling table, three-stage cutting system, stacker, and industrial chiller — is priced per configuration (please inquire for current quotation — varies with options and local duties). Typical payback period: 12-18 months at 70% capacity utilization. Operating cost for a standard 1220×2440×12mm board (~21.5 kg): PVC resin approximately 900/ton, 75% of formula), CaCO₃ filler ~2.15, electricity ~0.15/kWh), direct labor ~15/hr ÷ 60 boards/hr), packaging ~20.65 per board. Market selling price for PVC Celuka foam board 1220×2440×12mm: $28-38 per board depending on regional market conditions — yielding gross margins of 26-46%. Secondary value-add services (UV printing, CNC cutting, edge banding, lamination) further increase margin per board. For a detailed ROI calculation tailored to your local raw material costs, labor rates, and electricity tariffs, please contact Nicole at ceo@cxsljx.com.
Zhangjiagang Chenxing Machinery Co., Ltd. is a specialized plastics extrusion equipment manufacturer based in Zhangjiagang City, Jiangsu Province — China's premier hub for plastics machinery manufacturing, where over 60% of the country's extrusion lines are produced. Choosing Chenxing means partnering with a factory-direct manufacturer, not a trading intermediary — giving you direct engineering access, competitive factory pricing, and faster after-sales response.
Chenxing manufactures the full spectrum of plastic extrusion equipment, enabling single-source procurement and unified after-sales support for multi-line factories:
| Category | Products | Link |
|---|---|---|
| Pipe extrusion | PVC Pipe Extrusion Line | PE/PPR/PVC pipe lines, 16-630mm |
| Profile extrusion | PVC Roof Tile Extrusion Line | Roof tiles, wall panels, WPC profiles |
| Board extrusion | PVC/WPC Foam Board Line (this page) | Celuka + free-foam, 915-1560mm |
| Compounding | Plastic Pelletizer Machine | Single/twin-screw pelletizing lines |
| Recycling | Shredder Extruder Recycling | Post-industrial and post-consumer recycling lines |
| Auxiliary equipment | Auxiliary Machines | Heating Mixer, Hopper Dryer, Vacuum Loader, Chiller, Pipe Coiler |
| Single-screw | Single Screw Extruder, High-Output SSE | PE/PP extrusion |
See all products: Product Category | Application solutions: Solutions
Every Chenxing extrusion line ships with CE, SGS, and ISO certification documentation. Additional destination-market certifications (SASO, SONCAP, etc.) can be arranged upon request. Third-party inspection (SGS/Bureau Veritas/TUV) is welcomed and routinely accommodated — inspectors are provided full access to the production workshop and testing area.
Each machine purchase includes on-site installation and commissioning by a Chenxing engineer dispatched to your factory:
Engineer arrives at your facility with the machine shipment
Supervises mechanical installation, electrical connection, and utility hookup
Conducts trial production runs on your actual formulation
Trains your operators on startup, shutdown, troubleshooting, and daily maintenance
Remains on-site until your team achieves independent production at rated output
1-year comprehensive warranty on all mechanical and electrical components
1-year supply of wear-out spare parts included free of charge (screw tips, heater bands, seals, bearings, cutting blades)
Lifetime technical support via phone, video call, or on-site visit
Remote diagnostics: For issues that can be resolved remotely, our engineers guide your team via video call — no travel delay
On-site repair: If remote troubleshooting cannot resolve the issue within the warranty period, an engineer is dispatched to your factory at our cost
Zhangjiagang Chenxing operates from a modern manufacturing facility in Jingfeng Town Sanxing Industry Park, Zhangjiagang City. The factory is equipped with CNC machining centers, large-bed lathes, and a dedicated assembly and testing area where each extrusion line undergoes a full dry-run test with your specified formulation (or a standard formula) before disassembly and crating for shipment.
Every inquiry receives a personalized response from Nicole, our international sales manager, within 12 business hours. Here's what to expect:
Email ceo@cxsljx.com or message +8615951187228 (WhatsApp/WeChat) with the following details — as much or as little as you know:
- Target board width (915 / 1220 / 1560mm) - Target board thickness range (e.g., 5-20mm) - Desired daily output (tons/day or boards/day) - Application (furniture / construction / advertising / WPC) - Celuka (premium) or free-foam (economy)? - Your local: voltage/frequency, raw material availability, labor rate
Nicole will prepare:
Recommended model (SJSZ51/105 through SJSZ92/188) with justification
Complete equipment list with specifications
Detailed price quotation (FOB/CIF to your port)
Estimated shipping dimensions and container count
Production lead time
Payment terms (30% T/T deposit, 70% before shipment; L/C at sight; Trade Assurance)
Visit Zhangjiagang: Walk the production floor, see your machine in assembly, and run a trial on your actual formulation
Video inspection: If travel isn't feasible, we conduct a live video walkthrough of your completed machine running a production test
Third-party inspection: We welcome SGS, Bureau Veritas, or TUV inspectors at any stage
Machine is manufactured to your specifications (6-8 weeks standard lead time)
Pre-shipment inspection and test run
Container loading and sea/rail freight to your destination
Chenxing engineer dispatched to your factory for installation, commissioning, and operator training
Your team achieves independent production at rated output — typically within 3-5 days after power-on
Ready to start? Contact Nicole now:
| Channel | Detail |
|---|---|
| ceo@cxsljx.com | |
| Phone WhatsApp WeChat | +8615951187228 |
| Website | chenxingmachinery.com |
| Product Catalog | chenxingmachinery.com/product-category |
| Company Profile | chenxingmachinery.com/aboutus |
Inquiry response time: Within 12 business hours. For urgent inquiries, WhatsApp message typically receives a reply within 2 hours during China business hours (UTC+8, 8:00-18:00).