Everything You Need to Know About linear weigher

Introduction: Why a linear weigher matters when you buy weighing equipment

A linear weigher is a precise automated weighing device widely used in packaging lines for medium-to-large products. If you are searching to buy linear weigher equipment or comparing linear weigher suppliers, this guide gives practical, commercial-focused information to help you choose the right machine and integrate it into your production. It also explains typical performance, use cases, and maintenance best practices to protect your return on investment.

What is a linear weigher and when to choose one

A linear weigher, sometimes called a linear combination weigher, uses multiple weighing channels arranged in a straight line to measure product weight and drop defined portions into packaging machines. Compared with multihead weighers, linear weighers are often chosen for heavier, larger, or awkwardly shaped items and for simpler line configurations. If your priority is cost-effective handling of chunky products or straightforward integration with vertical form-fill-seal (VFFS) systems, a linear weigher can be the right choice.

Common commercial keywords: buy linear weigher, linear weigher supplier, linear weigher for sale

When buyers search with commercial intent terms like buy linear weigher or linear weigher supplier, they are typically evaluating price, throughput, accuracy, and after-sales support. Prioritizing a supplier with strong customization capabilities and service—such as Kenwei—reduces risk during procurement and startup.

How a linear weigher works: key components and operation

Understanding the core mechanics helps when evaluating technical specifications and supplier proposals.

Main components and principle

A linear weigher consists of multiple linear weighing channels, each with a small hopper and a load cell, a PLC or controller that calculates the best combination of channels to reach the target weight, a product feeding system, and a discharge gate that releases the combined portion to a packaging machine. Modern units use high-precision load cells, servo or stepper-driven gates, and touchscreen HMI for settings and diagnostics.

Typical operation on a production line

Product is fed to the linear channels via vibratory or conveyor feeders. The controller continuously weighs each channel and computes combinations to match the target weight with minimal overfill. When the set weight is achieved, selected channels open simultaneously, dropping the portion into a bagger or filler. Integration points include sync signals to VFFS machines, rejection devices, and upstream feeders.

Performance metrics: speed, accuracy, and capacity

These are the primary criteria buyers compare when choosing a linear weigher for commercial lines.

Accuracy and typical ranges

Linear weighers offer precise portioning, though exact accuracy depends on product characteristics and model. Typical industrial linear weighers achieve accuracy ranges from about ±0.1 g for very small precision systems to ±1–2 g for heavier bulk items. For large particulate or irregular shapes, expect accuracy to be lower than for free-flowing powders.

Throughput and capacity

Throughput varies by product, head count, and target weight. Typical outputs for linear weighers range from about 10 to 120 portions per minute. Machines designed for bulky items may focus on heavier portions with lower cycle rates, while high-speed units optimized for smaller portions achieve higher rates. Always verify supplier test data for your specific product.

Key benefits of using a linear weigher for packaging

Highlighting benefits helps justify purchase decisions to procurement and operations teams.

Benefit 1: Better handling of large or fragile products

Linear weighers are gentler on large, fragile, or irregular items because they use straight-line channels and simpler drop mechanisms, reducing product damage compared with high-speed multihead systems.

Benefit 2: Cost-effective for specific product ranges

For medium production volumes and heavier portion sizes, linear weighers often cost less than multihead alternatives while delivering the required accuracy, making them attractive for mid-size manufacturers or product lines with intermittent runs.

Benefit 3: Easier integration and customization

The linear layout simplifies integration with existing conveyors, fillers, and baggers. Suppliers like Kenwei provide customized infeed solutions, discharge chutes, and control interfaces to match your packaging line configuration.

Common applications and industries using linear weighers

Linear weighers are versatile across food and non-food sectors. Commercial buyers should match machine features to their industry requirements.

Food sector: snacks, frozen food, meat, bakery

Common uses include weighing frozen vegetables, chicken pieces, dumplings, bakery items, and snacks where portion integrity matters. Stainless-steel construction and washdown-capable designs are standard for hygiene compliance.

Non-food: hardware, chemicals, pharmaceuticals

Linear weighers handle heavy or irregular hardware parts, pelletized chemicals, and some pharmaceutical items when portion sizes are large and gentle handling is required. Clean-room or containment adaptations are available for regulated industries.

How to choose the right linear weigher supplier

Selecting a reliable linear weigher manufacturer affects long-term uptime and total cost of ownership.

Checklist for buyers: technical and commercial considerations

- Product testing: insist on in-kind product tests and documented trial data showing throughput and accuracy for your SKU.
- Customization: confirm the supplier can adapt feeders, hoppers, and discharge geometry.
- Build quality: look for food-grade stainless steel, IP65/IP66 washdown options, and hygienic design.
- Controls and interfaces: ensure compatibility with your PLC, VFFS, or bagmaker and remote diagnostics capability.
- Certifications and standards: check CE, ISO 9001, or relevant local certifications.
- After-sales service: evaluate local support, spare parts availability, and training offerings.
- Warranty and acceptance tests: negotiate factory acceptance testing (FAT) and on-site commissioning terms.

Installation, commissioning, and integration considerations

Proper installation and commissioning maximize performance and minimize startup delays on the packaging line.

Line layout and control integration

Plan the physical layout to maintain gentle product flow into the infeed and correct discharge alignment to the bagger or filler. Integrate control signals for start/stop, fault handling, and reject events. A synchronization module often reduces product spillage and ensures correct pouch filling.

Factory acceptance testing and training

Run FAT with your actual products and target settings. Require the supplier to provide operator and maintenance training, along with documentation and spare parts lists. Kenwei offers turnkey installation, commissioning, and user training to ensure rapid ramp-up.

Maintenance, hygiene, and longevity tips for linear weighers

Good maintenance extends useful life and preserves accuracy.

Daily and periodic maintenance tasks

Daily cleaning with appropriate detergents, visual inspection of load cells and gates, and clearing of product build-up is essential. Periodic calibration of load cells, firmware updates, and checking mechanical wear items such as gate seals and bearings should be scheduled per usage.

Hygiene and sanitary design

For food lines, select machines with sloped surfaces, minimal crevices, quick-release parts for washdown, and materials compliant with food safety standards to simplify cleaning and reduce contamination risk.

Why choose Kenwei as your linear weigher manufacturer and supplier

Kenwei is a leading manufacturer of multi-head weighers, linear weighers, metal detectors, and check weighers. With headquarters in Fusha High-tech Industrial Park, Zhongshan, Guangdong Province, Kenwei provides integrated automated weighing and packaging systems tailored to customer needs.

Kenwei commercial strengths: customization and global service

Kenwei emphasizes high-speed and high-precision machines and offers one-stop automated solutions including design, manufacturing, installation, commissioning, and after-sales service. The company holds a reputation for timely technical support and customized configurations, reducing the time to production for new lines. Visit https://www.kenweigroup.com/ for product catalogs and contact details.

Conclusion: making a confident purchase decision for a linear weigher

Choosing the right linear weigher requires evaluating your product characteristics, target throughput, accuracy needs, and integration requirements. Prioritize suppliers who provide in-kind product testing, robust after-sales support, and proven hygiene and build quality. A well-chosen linear weigher from a reputable manufacturer like Kenwei can lower packaging costs, reduce product damage, and improve line efficiency.

Frequently Asked Questions

What is the difference between a linear weigher and a multihead weigher?
A multihead weigher uses radial buckets arranged in a circular pattern for high-speed, small-to-medium products; a linear weigher uses straight-line channels and is better for larger, heavier, or irregular items and simpler integration.

How accurate is a typical linear weigher?
Accuracy depends on product and model. Typical ranges are ±0.1 g for small precision units up to ±1–2 g for heavier bulk portions. Always request supplier test data for your product.

What types of products are best suited to linear weighers?
Large or irregularly shaped foods (e.g., chicken pieces, dumplings), fragile items, and heavier hardware components are commonly handled by linear weighers.

Can a linear weigher integrate with my VFFS or pouch machine?
Yes. Most commercial linear weighers provide sync signals and mechanical interface options for VFFS, flow wrappers, and other packaging machines. Confirm compatibility during purchase.

How do I evaluate a linear weigher supplier?
Ask for in-kind product tests, FAT reports, references, details on warranty and spare parts, on-site commissioning services, and training offerings. Consider the supplier's global service footprint.

What maintenance is required for reliable operation?
Daily cleaning, regular calibration of load cells, inspection of gates and feeders, firmware updates, and scheduled replacement of wear parts. Suppliers often provide maintenance plans.

Does Kenwei offer customization for linear weighers?
Yes. Kenwei provides tailored infeed, discharge, control integration, and hygienic design options, plus turnkey installation and training to meet customer requirements.