Why Do Standard Multihead Weigher Packing Systems Vary So Much in Price?

Two quotations can describe almost the same system: a 14-head multihead weigher, an elevator, a platform and a packaging machine. The hopper capacity and advertised speed look similar, yet the prices are far apart.

Once you have matched the product, bag format, required output and equipment included, it is time to look at how each system is built.

A standard configuration still leaves many manufacturing decisions open: frame construction, steel thickness and grade, weighing components, machining, electrical assembly and testing. Each affects the manufacturer's cost, and several are difficult to judge from photographs or a short video.

When comparing a Smart Weigh proposal with another quotation, these are the details we suggest examining.

Machine Weight and Frame Stability

Start with the equipment's net weight, using the same scope of supply. A shipping weight that includes the crate and platform will tell you very little about the packaging machine itself.

Weight can indicate how much material has gone into the structure. The next question is where that material is used: the main frame, base, supporting members or external covers.

A multihead weigher needs a stable structure while nearby equipment is moving. External vibration transmitted through its supports can disturb the weight signal and increase the time needed for a stable reading. The Institute of Measurement and Control explains this relationship in its guide to dynamic weighing.

Frame stability also matters to the packaging machine. Film pulling, sealing and pouch handling involve repeated movement. Excessive frame deflection can affect alignment, although bag appearance also depends on film handling, gripper settings and sealing conditions.

Compare the frame sections, bracing, connections, feet and support platform. Adding weight to a cover does little to improve those features.

Steel Thickness Depends on the Part

A quotation stating “stainless steel construction” leaves another question unanswered: how much steel is actually used?

Ask about the thickness of the base, structural members, mechanism supports and outer panels separately. They do different jobs.

For comparable geometry and loading, an inadequately thin supporting part can deform more easily. A thin cover may suffer dents during handling. Those are different problems, with different consequences for the machine.

This matters when equipment travels by road, sea and road again before installation. Handling and installation create further opportunities for contact damage. Suitable crating, anchoring and transport supports also influence whether it arrives in good condition.

Thicker material adds cost, but thickness should follow the function of the part. Weigh hoppers, for example, have their own requirements for mass and response. A useful comparison identifies the material used in specific locations rather than asking for one thickness for the entire system.

Verify the Stainless Steel Grade

SUS201, SUS304 and SUS316 can have similar-looking surfaces. A polished photograph cannot establish which grade was used.

The grade affects suitability for the product, moisture exposure and cleaning environment. Also check whether a quotation specifies the material for product-contact parts, the frame, the enclosure or all of these.

At Smart Weigh, we check incoming stainless steel sheets to verify the specified SUS304 or SUS316 grade. This is a manufacturing step that a finished-machine photograph cannot show.

For a purchase comparison, ask for the material specification, supporting material documents and the supplier's verification method. Alloy identification uses composition differences to distinguish materials.

Select the grade for the actual operating environment. Using 316 in a demanding application may be justified; specifying it throughout a dry-product system needs its own justification.

Compare the Complete Weighing System

The head count and hopper volume describe only part of a multihead weigher.

Look further into the load cells, their capacity and mounting, the signal electronics, feeder control and hopper mechanisms. A load cell is the sensor that converts the applied load into a measurable signal. Its response and the way it is installed matter alongside its stated accuracy.

During operation, product enters a hopper, the weight signal settles, a combination is selected and the chosen hoppers discharge. The feeder settings, gate movement and control software must work together within that cycle.

Two hoppers with the same stated volume can also differ in shape, gate clearance and surface finish. Product remaining inside or taking longer to discharge changes how the system runs.

Ask for consecutive weight results at your required speed, including average overfill and packs outside the agreed limits. A display showing small weight increments, or a successful static calibration, provides only part of the evidence.

Small differences add up. At an output of 100,000 packs per day, an average extra fill of 0.5 g amounts to 50 kg of product daily. Use your own production figures to assess the value of tighter weight control.

Internal Moving Parts Deserve Attention

The PLC and motor brands usually receive plenty of attention. Bearings, shafts, guides, reducers, cams and belts can be just as important to the comparison, depending on the machine design.

Their specifications, machining and installation all contribute to cost. Shaft fits, alignment, clearances and lubrication need to suit the load and operating cycle. Holding those fits and alignments consistently requires manufacturing checks and assembly work.

A mechanism can move successfully during a brief demonstration while leaving questions about wear and repeatability over sustained production. Useful checks include the exact component models, movement consistency and the manufacturer's inspection records.

Ask how the frequently serviced parts are accessed and replaced, too. A bearing buried behind several assemblies can require more maintenance work than an accessible one. This is a practical design difference worth discussing before purchase.

Forming and Sealing Require Precise Assembly

On a vertical packaging machine, the forming collar, film-pulling arrangement and sealing assembly work together to produce the bag.

Forming surfaces, alignment and consistent film movement deserve attention. At the sealing jaws, the relevant details include face alignment, pressure distribution, heating and temperature measurement.

Seal quality depends on pressure, temperature, contact time and cooling conditions. A temperature controller alone cannot establish how well the entire assembly performs.

For a premade pouch packing machine, also examine how the grippers hold the pouch and how the mouth is presented to the sealing station. Uneven positioning can introduce wrinkles even when the temperature setting is correct.

These parts require machining, assembly adjustment and verification. Compare consecutive finished bags using the same product and packaging material. Check bag shape, seal consistency, trapped product and the appropriate seal-strength or leak-test results.

Welding and Finishing Add Manufacturing Work

Buying the correct stainless steel is one stage. Cutting, welding, finishing and cleaning it are further stages that require labour and inspection.

Look inside hoppers, underneath the platform and behind the visible panels. These areas can reveal sharp edges, unfinished joints, difficult-to-clean gaps and inconsistent workmanship.

Surface condition matters to corrosion resistance. Outokumpu's guidance on treatment after fabrication explains why welding oxides and contamination may require appropriate removal.

The finish should also suit the product. Some applications benefit from textured contact surfaces, while others need a different treatment to support product flow and cleaning.

Ask for close photographs of representative internal areas and an explanation of the finishing process. A brightly polished front panel offers limited information about these less visible details.

Electrical Assembly Goes Beyond Component Brands

Two systems can use the same PLC brand and still have different electrical construction.

Cable selection, terminal connections, shielding, grounding, cable restraint, cabinet ventilation and entry seals all need attention. The arrangement of sensitive weighing signals around power wiring is another detail to examine.

Clear wire identification and usable electrical drawings also affect how easily maintenance staff can trace a fault.

Control software deserves a demonstration. Ask what happens when product runs low, a pouch fails to open or the operator stops and restarts the system. Check whether the fault message helps the operator find the cause.

These details involve engineering and assembly time. Request the component models, cabinet photographs and drawings, and confirm which areas are suitable for the intended cleaning method.

Check What Was Tested Before Shipment

A standard system still needs its individual assemblies checked and its machines coordinated.

The elevator must supply product appropriately. The weigher must release a portion when the packaging machine is ready, and the product must clear the sealing area in time. On a pouch system, an unsuccessful bag-opening cycle should prevent product discharge.

Agree on a test using representative product and packaging material, with the weight, speed and acceptance limits recorded. Include normal running and relevant stop-and-restart conditions.

The value of testing lies in what was checked, what the results showed and whether identified problems were corrected and retested. A statement that the machine ran for several hours leaves those questions open.

Before dispatch, also clarify how the equipment is secured, which components need protection and whether any transport supports require removal during installation.

Ask for Evidence Behind the Price

Use a short comparison sheet to bring the discussion back to specific manufacturing choices.

A higher quotation should have an explanation you can verify. A lower quotation may also be suitable when its construction and tested performance meet your requirements. Give each supplier the same opportunity to explain the details.

For a Smart Weigh system, send your product information, target weight, bag dimensions, packaging material, required output and cleaning conditions. Discuss your project with our team, and use those requirements to compare the proposed configuration, construction and test conditions.