How We Designed a Filling Line for a Customer's Viscous Product
In This Guide
Explore the engineering considerations behind the ZS-FAL180G6 viscous-product filling line, from servo piston dosing to capping, induction sealing and labeling. Use the section links below to review equipment specifications, line balancing and testing requirements.
Designing a filling line for a viscous product requires more than choosing a machine with the right filling volume. Product flow characteristics, dosing consistency, container compatibility, closure requirements, and production capacity all influence the final configuration.
For manufacturers producing lotions, creams, detergents, pastes, and other viscous materials, these factors must be considered together to create a coordinated packaging process.
In this ZONESUN engineering case, we examine how a multi-stage filling and packaging line can be configured around a viscous product application. The ZONESUN ZS-FAL180G6 integrates six-head servo piston filling, automatic cap feeding and capping, induction sealing, and round bottle labeling into one packaging solution.
The following sections explain the engineering considerations behind this configuration and how each stage contributes to the overall workflow.
1. Understanding the Requirements of a Viscous Product
The first step in designing a filling line is understanding the material being handled and the packaging requirements.
Viscous products behave differently from water-like liquids. Depending on their formulation, they may flow slowly, cling to filling nozzles, form strings during dispensing, or require a controlled feeding process to maintain consistent dosing.
Before selecting equipment, manufacturers should evaluate several factors.
Product viscosity and flow behavior
The product's flow characteristics influence the filling mechanism, nozzle dimensions, and dispensing speed. Some lotions flow relatively easily, while thicker creams and pastes may require a positive-displacement filling system.
Filling volume
The required dose determines the appropriate metering range. The machine must accommodate the target volume while maintaining the required filling consistency.
Container dimensions
Bottle diameter, height, opening size, and material affect filling nozzle positioning, cap handling, and labeling accuracy.
Closure and sealing requirements
Some products require screw capping alone, while others need an additional inner seal to support package integrity. The closure system must match the actual bottle and cap design.
Production capacity
The filling, capping, sealing, and labeling stages must operate at compatible speeds. The production target should be evaluated across the complete line rather than from the filling machine alone.
These requirements establish the basis for selecting and configuring the equipment.
2. Selecting a Six-Head Servo Piston Filling System
For this application, the ZONESUN ZS-FAL180G6 uses the ZS-YT6T-6PX servo filling machine, equipped with six filling heads and a servo piston pump system.
Product dosing is performed through piston-driven displacement. This filling method is commonly used for compatible lotions, creams, pastes, and other viscous products because it provides controlled dispensing without relying solely on gravity.
The six-head configuration allows multiple containers to be filled during the same operating cycle, helping support higher output than a comparable single-head setup.
Key Filling Specifications
- Filling heads: 6, customizable
- Filling range: 100–1,000 mL, customizable
- Listed filling speed: Approximately 30–70 bottles/min, depending on material and bottle size
- Filling accuracy: ±1%
- Pump type: Servo piston pump
- Power: 2 kW
- Air pressure: 0.5–0.8 MPa
These are the listed specifications for the filling machine, not a guaranteed sustained output for every complete production line.
Actual performance depends on the product's flow behavior, target dose, container dimensions, nozzle configuration, and the operating speeds of the downstream machines.
Why Product Testing Matters
Even when two products have similar viscosities, their filling behavior can differ because of formulation, temperature, entrained air, and other material characteristics.
A filling test can help determine whether the selected nozzle diameter, dispensing speed, and piston settings are appropriate for the application.
For products that tend to drip or form strings, an anti-drip nozzle can also be customized where suitable.
The objective is to establish a stable filling process before finalizing the line configuration.
3. Integrating Automatic Cap Feeding and Capping
After filling, containers move to the closure section.
The ZS-FAL180G6 configuration includes a cap feeding system and a servo capping machine. The cap feeding equipment is designed to position compatible caps for subsequent application, reducing the need for manual cap placement.
The servo capping unit supports controlled cap application. Its configuration must be matched to the bottle neck, cap dimensions, and closure type.
Listed specifications for the capping machine include:
- Suitable bottle height: 50–300 mm
- Suitable bottle diameter: 30–120 mm
- Suitable cap diameter: 20–60 mm
- Listed working speed: Approximately 40 bottles/min
These dimensions and speeds should be verified against the customer's actual packaging samples.
Cap feeding capacity can also depend on cap geometry and the feeding arrangement. The complete line should therefore be tested with the intended caps rather than assuming that the filling section's maximum speed will automatically apply to the capping section.
4. Adding Induction Sealing for Package Integrity
For applications that require an inner foil seal, the production line can incorporate the ZS-FK6000 water-cooled induction sealing machine.
Induction sealing uses electromagnetic energy to heat a compatible foil liner and bond it to the container opening under suitable operating conditions.
When the bottle, liner, and closure are compatible, this process can help create a sealed package and reduce the risk of leakage during handling and distribution.
The listed equipment specifications include:
- Sealing speed: Approximately 0–80 bottles/min
- Sealing diameter: 15–60 mm, customizable
- Suitable bottle materials: Compatible plastic and glass bottles
- Cooling method: Water cooling
- Power: 3.6 kW
The sealing system is not suitable for every bottle and closure combination. The product page specifies limitations for metal bottles, metal caps, and glass caps.
Before production, the bottle material, cap structure, foil liner, and sealing conditions must be checked together. Sealing performance should be verified using the intended packaging components.
5. Connecting the Round Bottle Labeling System
Once the containers have been filled, capped, and sealed, labeling provides product identification and supports a consistent presentation on the production line.
The ZS-FAL180G6 includes the ZS-TB260R round bottle labeling machine. Its three-roller labeling structure is designed for compatible round containers and can support single-side, double-side, and wraparound labeling configurations.
Listed specifications include:
- Labeling capacity: Approximately 25–50 bottles/min, depending on bottle size
- Labeling accuracy: ±1.0 mm
- Suitable bottle diameter: 30–100 mm
- Suitable bottle height: 30–200 mm
- Label length: 20–300 mm, customizable
- Label height: 12–130 mm, customizable
Bottle dimensions, label material, label position, and container surface conditions should be checked before selecting the final setup.
Labeling speed also needs to be coordinated with the preceding operations. A line's practical output is determined by the complete process, not by adding together the maximum speeds listed for individual machines.
6. How the Complete Filling Line Works
The ZS-FAL180G6 combines multiple packaging stages into a coordinated production workflow.
The configuration can be summarized as follows:
Stage 1 — Bottle feeding
The bottle sorting machine supplies containers to the production line. Its listed operating speed is approximately 20–80 bottles/min, depending on the bottle configuration.
Stage 2 — Six-head filling
The servo piston filling machine dispenses the specified quantity of product into the containers.
Stage 3 — Cap feeding and capping
Compatible caps are automatically supplied and applied to the filled containers.
Stage 4 — Induction sealing
Where required, the induction sealing unit applies a compatible foil liner seal.
Stage 5 — Round bottle labeling
The labeling machine applies the selected label format to the finished containers.
Stage 6 — Finished product discharge
Labeled containers are discharged for subsequent inspection, collection, or downstream packaging.
This configuration brings filling, capping, sealing, and labeling together in one production system. Additional equipment can be considered if the project requires inspection, carton forming, or automatic case packing.
7. Matching Equipment Speeds Across the Line
One important consideration when designing a multi-stage filling line is the relationship between the rated speeds of individual machines.
For example, the filling machine may have a listed speed of 30–70 bottles/min, while the capping machine is listed at approximately 40 bottles/min and the labeling machine at approximately 25–50 bottles/min.
These figures represent the individual machines' stated capacities under applicable conditions. They do not establish a guaranteed line-wide production rate.
The final operating speed depends on the actual product, bottle size, cap design, labeling requirements, transfer timing, and any buffer capacity between machines.
During project planning, the equipment configuration should be reviewed as a complete system. Where necessary, machine settings, conveyor arrangements, or individual station configurations can be adjusted to support a compatible production workflow.
This approach helps establish realistic output expectations before the equipment is commissioned.
8. Testing and Verifying the Final Configuration
Before a customized filling line is approved for production, testing should focus on the actual product and packaging components.
The verification process may include:
- Filling consistency: Check the dispensed quantity across repeated filling cycles.
- Nozzle performance: Observe dripping, stringing, and residue around container openings.
- Cap application: Confirm stable cap placement and appropriate closure performance.
- Induction sealing: Verify seal formation using the intended bottle, cap, and foil liner.
- Labeling quality: Check label position, alignment, and adhesion.
- Integrated operation: Confirm that the different stations transfer containers smoothly and operate at compatible speeds.
The acceptance criteria should be established according to the customer's product specifications and production requirements.
Where adjustments are necessary, the filling parameters, nozzle arrangement, closure settings, or labeling configuration should be reviewed before regular production begins.
9. A Configurable Filling and Packaging Solution from ZONESUN
The ZONESUN ZS-FAL180G6 illustrates how several packaging operations can be combined into a single production line for compatible viscous products.
Its configuration includes six-head servo piston filling, automatic cap feeding and capping, induction sealing, and round bottle labeling. Filling range, nozzle quantity, and selected machine configurations can be customized according to the application.
The appropriate setup depends on the product's flow behavior, filling volume, bottle dimensions, cap design, sealing requirements, label format, and target production capacity.
For manufacturers planning a similar project, preparing product and packaging samples can help the engineering team evaluate equipment compatibility and determine the configuration needed for the intended production process.
Planning a filling line for a viscous product?
Contact ZONESUN to discuss your product characteristics, filling volume, container specifications, and production target.
Explore the ZONESUN ZS-FAL180G6 Automatic Paste Filling, Capping and Labeling Packaging Line for more equipment details.
Frequently Asked Questions
Is the ZS-FAL180G6 suitable for thick creams and pastes?
The line uses a servo piston filling system, a technology commonly considered for compatible creams, pastes, lotions, and other viscous materials. Final suitability depends on the actual product characteristics and filling requirements.
What is the filling range of the ZS-FAL180G6?
The listed filling range is 100–1,000 mL, with customization available. The required dose should be confirmed when configuring the machine.
Can the line handle different bottle sizes?
The equipment has defined bottle and label size ranges, and selected configurations can be customized. Actual bottles should be evaluated to confirm compatibility with the filling, capping, sealing, and labeling sections.
Does the line include induction sealing?
Yes. The listed configuration includes a water-cooled induction sealing machine. The bottle, cap, and foil liner must be compatible with the selected sealing process.
Can the line be customized for a specific production capacity?
Selected equipment configurations can be customized. The target capacity should be evaluated across the complete line because the filling, capping, sealing, and labeling stages may have different operating speeds.
What information should I provide when requesting a quotation?
Provide the product type, viscosity or flow characteristics, filling volume, bottle dimensions, cap type, sealing requirements, label specifications, and target output. Product and packaging samples can help verify the suitability of the proposed configuration.
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