What Is a Four Side Sealing Pouch Making Machine?
A four side sealing pouch making machine — also referred to as a 4-side seal bag maker, flat sachet machine, or quad seal pouch machine — is specialized flexible packaging equipment that seals all four edges of a flat film to produce hermetically closed pouches. Unlike three-side seal or back-seal configurations, the 4-side format encloses the product with equal seams on every side, delivering maximum barrier integrity and a premium finished appearance.
The Xuanhai four side sealing pouch machine is purpose-built for high-volume flexible packaging lines. Powered by a dual servo motor drive system and managed through an advanced PLC + HMI touchscreen interface, it produces uniform, airtight flat pouches — from compact single-serve sachets to larger industrial bags — with output rates reaching 100 pouches per minute.
Compatible with virtually all commercially available heat-sealable laminates — including BOPP/PE, PET/CPP, PET/aluminum foil/PE, and paper-based composites — this machine serves manufacturers across the food, pharmaceutical, cosmetic, agricultural, and chemical packaging sectors.
8 Engineering Features That Set This Machine Apart
Dual Servo Motor System
Independent servo motors for film feeding and bag cutting deliver ±0.5mm dimensional accuracy. Eliminates slippage and ensures registration on printed films.
PID Digital Temperature Control
Separate PID controllers for each sealing zone (top, bottom, left, right) stabilize heat within ±1°C — preventing burn-through on thin films and cold seals on thick laminates.
PLC + 7" HMI Touchscreen
Centralized parameter management: set bag dimensions, dwell time, cutting speed, temperature profiles, and production counters from a single intuitive interface.
High-Precision Photoelectric Sensor
Julong-brand edge alignment and registration sensor tracks print marks in real time, maintaining precise cutting alignment even at maximum speed on decorated films.
Constant Auto-Tension Control
Dancer-roller unwinding system with AC inverter maintains stable film tension across all running speeds, preventing wrinkling, stretching, or misalignment during long production runs.
Auto-Stop Safety System
Integrated sensors automatically halt production on film break, temperature deviation, or jam detection — protecting both the operator and the film material.
Pneumatic Punching & Notch Options
Optional pneumatic modules for tear notches, euro-slot holes, round punches, and static elimination. Rhythm can be pre-set as continuous, interval, or stop-mode.
Variable Frequency Drive (VFD)
Inverter-controlled main motor reduces energy consumption at lower speeds, extends component lifespan, and allows smooth ramp-up without mechanical shock.
How the 4-Side Seal Bag Making Process Works
The complete production cycle runs automatically from roll to finished pouch in six synchronized stages:
Film Unwinding & Tension Management
Laminated film unwinds from the roll through a dancer-controlled buffer system. Auto-tension maintains consistent feed speed regardless of roll diameter change.
Film Folding & Pouch Forming
The flat web is folded or guided into the correct orientation for the 4-side seal format. Guide rollers and edge alignment sensors ensure centerline accuracy.
Longitudinal (Side) Heat Sealing
Heated sealing bars create continuous vertical seams on both sides of the film. PID-controlled temperature prevents cold or overheated seals on all laminate types.
Cross (Top & Bottom) Sealing
Reciprocating horizontal sealing bars close the top and bottom of each individual pouch, completing the four-side hermetic seal. Adjustable dwell time accommodates different film structures.
Precision Cutting & Separation
Servo-driven cutting station separates individual pouches from the web with a clean, straight edge. Optional wavy-cut or shaped dies can be installed for premium presentations.
Discharge & Counting
Finished flat pouches are conveyed to the output collection area. An integrated electronic counter tracks total output and can trigger auto-stop at a pre-set batch quantity.
Full Specification Sheet
| Parameter | Specification | Notes |
|---|---|---|
| Model | SBF-350 (4-Side) | Custom models available |
| Production Speed | 60 – 100 pcs/min | Varies by bag length & film type |
| Max Bag Width | Up to 350 mm | 500mm model available |
| Bag Length Range | 60 – 600 mm | Adjustable via servo |
| Film Thickness | 40 – 120 μm | Single & multi-layer laminates |
| Compatible Films | BOPP, PET, CPP, PE, Nylon, Aluminum Foil | All heat-sealable composites |
| Max Film Roll Diameter | Ø 500 mm | Single roll unwinding |
| Sealing Method | Four-zone heat sealing (top, bottom, left, right) | PID per zone |
| Sealing Temperature | 0 – 300°C | ±1°C stability |
| Drive System | Dual servo motor | Independent feed & cut control |
| Control Interface | PLC + 7-inch HMI touchscreen | English & Chinese UI |
| Registration Sensor | Photoelectric (Julong) | Print-mark tracking |
| Power Consumption | ≈ 4.5 kW | VFD-optimized |
| Power Supply | 380V / 3-phase / 50Hz | 220V custom available |
| Machine Dimensions | 2400 × 800 × 1400 mm (L×W×H) | Approx. |
| Machine Weight | ≈ 800 kg | |
| Certification | CE |
* Specifications subject to variation based on custom configuration. Contact our technical team for exact parameters matching your production requirements.
Compatible Packaging Films & Laminate Structures
The four side seal bag making machine is engineered to process virtually every commercially available flexible packaging substrate. Typical multi-layer film structures used for flat pouches include:
| Film Structure | Typical Application | Seal Temp. Range |
|---|---|---|
| BOPP / PE | Snack food, condiment sachets | 130 – 160°C |
| PET / CPP | Food vacuum, sample pouches | 140 – 170°C |
| PET / Al foil / PE | Coffee, pharmaceutical, pet food | 150 – 180°C |
| Nylon / PE | Wet food, high-barrier packaging | 145 – 175°C |
| Paper / PE composite | Eco-friendly consumer packaging | 120 – 150°C |
| BOPP / BOPP | Transparent display pouches | 125 – 155°C |
| Al foil / PE / PE | Medical sachets, mask pouches | 155 – 190°C |
Industries & Products Packaged with 4-Side Seal Pouches
The flat, hermetically sealed structure of a four-side seal pouch makes it ideal for single-serving, sample, or precise-dose products across a wide spectrum of industries:
Food & Beverage
Sugar sachets, seasoning pouches, instant coffee, sauce samples, granola portions
Pharmaceutical
Tablet blisters, powder sachets, oral rehydration salts, medicine unit-dose packs
Cosmetics & Personal Care
Face mask pouches, serum samples, shampoo sachets, wet wipes packaging
Agricultural
Seed packets, fertilizer sachets, pesticide single-use doses
Chemical & Industrial
Detergent pods, desiccant packets, adhesive samples, cleaning solutions
Pet Food
Single-serve wet food portions, supplement sachets, treat pouches
Four Side Seal vs. Three Side Seal vs. Back Seal: Which Is Right for You?
Choosing the correct pouch sealing format significantly impacts production cost, barrier performance, and shelf presence. Here is a direct comparison to guide your machine selection:
| Feature | Four Side Seal | Three Side Seal | Back (Center) Seal |
|---|---|---|---|
| Number of sealed edges | 4 edges | 3 edges | 1 back seam + 2 ends |
| Barrier integrity | ★★★ Excellent | ★★☆ Good | ★★☆ Good |
| Print surface (front & back) | ✔ Full print area both sides | ✔ Full print both sides | ✘ Back seam reduces space |
| Ideal pouch size | Small to medium (sachets to 350mm) | Small to large (up to 500mm) | Small cylindrical packs |
| Typical products | Sachets, single-serve, mask pouches | Snack bags, vacuum food bags | Coffee sticks, sugar straws |
| Film waste | Low (single web) | Low (single web) | Very low |
| Stand-up capability | ✘ Flat format | ✘ Flat format | ✘ Flat/cylindrical |
Bottom line: For brands requiring premium single-serve packaging with superior barrier protection and maximum printable surface area — particularly in pharmaceutical, cosmetic, and food sachet categories — the four side seal format is the preferred choice.
Four Side Sealing Pouch Machine — Buyer's FAQ
What is the minimum order quantity (MOQ) for this machine?
What film materials are compatible with the four side sealing pouch machine?
What production output speed can I expect?
Can the machine be integrated with an automatic filling line?
What optional accessories or add-ons are available?
How is after-sales service and spare parts supply handled?
What certifications does the machine carry?
35+ Years Manufacturing Flexible Packaging Machinery
Established in 1988 in Ruian, Zhejiang — China's recognized hub for packaging machinery manufacturing — Ruian Xuanhai Machine Co., Ltd. has built its reputation on three decades of uninterrupted production and continuous engineering improvement.
What Distinguishes Xuanhai from Competing Suppliers
Direct factory pricing: With no intermediary distributors, our ex-factory pricing is typically 25–35% below equivalent equipment sold through trading companies — without compromising component quality or build standards.
Component-level transparency: We specify the brand and model of every imported component — Panasonic servo drives, Julong sensors, Airtac pneumatics — so you can independently verify quality before purchase.
Long production verification: Every machine undergoes a minimum 72-hour continuous test run under load before dispatch. Run videos are recorded and shared with the buyer prior to shipment.
Global installation base: Xuanhai equipment is operating in production facilities across North America, Europe, Southeast Asia, the Middle East, and Africa. Our global network means local technical contacts are available in most major markets.
