Low Level Palletizer

A low level palletizer takes product at floor level, forms each layer close to the floor, and moves the layer or the pallet vertically to build the load. It is the simplest conventional design to integrate, because the infeed matches the height of standard line conveyors and most parts can be reached without climbing. This guide goes deeper into the machine itself: the floor-level infeed, how layers form low and are lifted, operator access, footprint, and the rate range in qualitative terms. For the general comparison with the elevated design, see the conventional palletizers guide, and for the other half of the pair, the high level palletizer guide. The palletizing systems overview shows where both fit.

How it works

The machine does its work at or near conveyor height, so the sequence looks different from an elevated design.

Cases arrive on a conveyor at about waist height. Several suppliers give a typical infeed height of about 30 to 36 inches, or 75 to 90 centimeters, similar to case sealers and line conveyors, so the machine can often connect to an existing run without a lift. One modular design lists an adjustable infeed height range far wider than that, so the figure is a typical value, not a rule.

On the infeed conveyor, cases are re-oriented as the pattern requires. A supplier of a floor-level machine describes the sequence this way: product is rotated for correct orientation before the row-formation area, and completed rows are pushed onto a layer-forming area, which may be a table depending on the design. Rows accumulate into a complete layer. Case size, count per row, and pattern matter most at this stage, and the machine may square or compress the layer here.

The complete layer then advances to a plate. Either the plate and layer travel up or down to align with the stationary pallet or the layer beneath, or a hoist raises the pallet platform to the plate. A manufacturer guide describes this vertical travel on every layer as what mechanically sets the low-level design apart, and as the main reason low level machines generally run at lower cycle rates. As the load grows taller, the travel distance per layer increases, which adds some cycle time on tall pallets.

An empty pallet is supplied from a magazine or by an operator, sheets are added if needed, and the finished pallet leaves on a discharge conveyor. One supplier notes that its discharge conveyor is elevated, with the load then moving on to storage or wrapping.

Types and configurations

Low level machines vary mainly in how the layer moves and how product is collected.

Layer lifted to a stationary pallet

In some designs the pallet stays in place at conveyor level and a platform lifts the formed layer from underneath to set it on the layer below. The footprint is mostly horizontal, and the pallet can be easy to reach for inspection or removal.

Pallet raised to the layer

A hoist raises the pallet platform to the layer-forming plate, then the plate withdraws and the load lowers. This mirrors the high-level motion, but the plate stays near the floor and the pallet travels a long way. Ask how the hoist handles a full pallet at the highest layer.

Row-by-row designs

Most low level machines handle a full layer at a time, but at least one modular design builds the load row by row. Its manufacturer says placing completed rows directly on the stacking plate keeps floor space small, and that the plate pulls out in two directions so the load is solid. The manufacturer also says that handling rows can reduce the need for intermediate sheets because case edges line up, which is a claim to test with your own case. Such designs may also place empty pallets and sheets using the same plate, which avoids a separate magazine.

Single and multi-infeed machines

A single infeed is simplest. Some low level machines accept more than one infeed, which can help a plant combine two lines in one footprint. Comparisons note that the horizontal layout of a low level machine can need more floor area than an elevated design, while compact models exist, so require a drawing for every design.

Rate, described qualitatively

Rate is the main limit, so read it carefully. A low level machine is generally intended for moderate throughput, which suits many single-line packaging operations but not the highest-speed beverage or snack lines. Suppliers describe the ceiling in different ways. One manufacturer guide states about 1 to 3 layers per minute for low-level machines, compared with about 5 to 10 for high-level ones. A separate comparison describes roughly 10 to 30 cases per minute, and one product page for a floor-level machine gives a specification of 10 to 20 cases per minute. These are not the same measure and do not apply to every design, so treat them as indications.

Three practical points follow. Cases per minute equals layers per minute times cases per layer, so a pattern with more cases per layer raises case rate at the same layer rate. A tall pallet adds travel per layer. And the rate should be stated for a specific case, pattern, and pallet height, and should include pallet changes. If the upstream line runs faster than the machine, product will accumulate and the line will stop, which is why the rate should be checked at the highest sustained line speed, not the average.

Specifications to evaluate

Package compatibility

Low level machines handle a broad range of packages, and that breadth is part of their appeal.

Corrugated cases and cartons are the standard use, and rigid cases at moderate rates form clean layers. Shrink packs and trays are common, subject to the grip and sliding behavior of the film. Some suppliers list bags among the handled products, and bag-specific low-level machines exist. Compression and layer squaring help, but test with the real bag at the real rate. One manufacturer lists buckets, crates, and jerrycans for its row-by-row design. Pails and irregular shapes are often better suited to robots, though specialty machines exist.

Check size limits. One supplier of a floor-level machine lists a product size range of 100 to 600 millimeters long and wide, and a payload range of 5 to 200 kilograms, for a single model. Another lists a different range for its modular design. These figures show how much the limits differ between machines, so ask for the limits of the specific model.

Integration upstream and downstream

Because the infeed sits at conveyor height, the machine usually connects directly to a case sealer, labeler, or check weigher, which is a main reason plants choose it. One supplier says it works well alongside case packers and sealers at the same height. The case conveyors page explains how cases move between those stations, and the accumulation conveyors page covers the buffer that keeps the packer running while a pallet changes. Since low level machines form layers on the floor, the accumulation area is often horizontal, and one comparison warns that it may take more floor space and have a limit on how much it can hold.

If the plant already uses overhead conveyors, product must come back down to the infeed height on a decline conveyor, which adds cost and complexity.

Downstream, the finished load leaves toward a stretch wrapper, labeler, or pallet conveyor. Check the discharge height and pallet buffer, because a slow wrapper can hold up a moderate-rate machine just as it does a faster one. Forklift traffic matters too: one supplier notes that forklift operators can watch the case infeed while handling pallets, which can be a benefit if the layout allows it.

For plants with lower ceilings and mixed products, see food packaging and pallet handling.

Footprint, utilities, controls, and safety

Low level machines fit within standard factory ceilings, with one guide giving about 4 to 6 meters, versus about 5 to 7 meters or more for high-level machines. Floor area depends on the design. A compact modular model lists a footprint of about 9 square meters, roughly 100 square feet, which shows what a small design can use. Always add pallet staging, magazines, accumulation, and forklift paths.

Suppliers say a major advantage is that most components can be reached from the floor, with no platform to climb for maintenance, changeovers, or jam clearing. That reduces downtime and can improve safety, but it does not remove the need for lockout procedures and guarded access to moving layer plates and lifts.

Expect electrical power and compressed air, so ask for the connected load and air use. A PLC and HMI manage the pattern and recipe. Ask how patterns are created, stored, and changed, and how the machine signals the packer and wrapper.

Layer plates, pallet lifts, and pallet exits are hazards even at floor level. Safeguarding commonly combines guards, interlocked doors, light curtains, and controlled-entry procedures. ISO 13849-1 defines performance levels for safety-related control functions, and a design with a robot adds ISO 10218 and ANSI/A3 R15.06. Editions change, so confirm which apply. A site risk assessment of the complete installation should set the safeguarding.

Cost factors

This guide does not state prices. Suppliers generally describe low level machines as less expensive than high-level equivalents, with lower installation cost where no elevated conveyor is needed, and the palletizer cost guide explains how to compare quotes. The main drivers are:

• Rate class and the number of infeeds
• Layer movement method and hoist capacity
• Layer squaring or compression features
• Pallet magazine and sheet handling
• Accumulation conveyors and any decline conveyor from overhead lines
• Guarding, light curtains, and controlled-entry access
• Controls platform, patterns, and integration with line equipment
• Wrapper interface and discharge conveyors
• Installation, commissioning, training, and spare parts

Because the rate ceiling is harder to raise later, include the cost of replacement or a second machine if line speed is expected to grow.

Selection checklist

• Measure the existing conveyor height and ceiling clearance.
• Define the sustained cases per minute at the highest line speed.
• List case sizes, weights, patterns, and pallet sizes and heights.
• Convert required cases per minute into layers per minute.
• Decide the number of infeeds and the accumulation space available.
• Request a layout drawing that includes pallet staging and forklift paths.
• Specify pallet and sheet handling.
• Confirm which service points can be reached from the floor.
• Request the safeguarding approach and the standards applied.
• Ask about the changeover method and time on the hardest change.
• Ask what happens if line speed grows.
• Request an acceptance test with production cases.

Common mistakes

• Assuming the rate will keep up with the line. Check the highest sustained rate, not the average.
• Ignoring tall pallets, since cycle time grows with the vertical travel.
• Forgetting accumulation. The layer-forming stage needs a buffer and floor space for it.
• Treating floor-level access as a safety case. Guarding and lockout still apply.
• Skipping the layout drawing. Floor use differs between designs, so verify.
• Overlooking existing overhead conveyors, since a decline conveyor adds cost.
• Underestimating changeover. Mechanical changes consume production time.
• Buying for today only. The rate ceiling can be hard to raise later.

Alternatives

A high level palletizer forms layers at an elevated infeed and generally reaches higher rates, fits plants with overhead conveyors and tall ceilings, and needs a lift and platforms. A robotic palletizer suits many SKUs, mixed shapes, and frequent pattern changes, and the robotic vs conventional palletizer guide sets out the comparison. The guide to choosing a palletizer helps weigh them against the same package list and rate, and the case palletizers page covers case handling that applies to every architecture. If the plant has low ceilings, floor-level conveyors, and moderate output, a low level machine is usually the first design to price.