Pallet conveyor (roller and chain conveyors for loaded pallets)

01

Start from the pallet and its heaviest load

The European Pallet Association specifies the EPAL Euro pallet as 1,200 × 800 mm and 144 mm high, weighing about 25 kg, with a safe working load of 1,500 kg; when laden pallets are stacked on a solid, even surface, the bottom pallet must carry no more than 5,500 kg. Its deck and bottom boards are 22 to 24 mm thick, and the bottom boards are chamfered on both long upper edges. [1]

EPAL lists faults that make a Euro pallet non-exchangeable, among them a missing board or block, blocks twisted more than 10 mm, and boards broken across or diagonally. [1] Editorial note: give the supplier every pallet type and condition the line will see, including plastic pallets, and ask how damaged pallets will be detected and rejected.

Give the supplier the pallet types, sizes and conveying direction, heaviest and lightest loads, load height and stability, throughput in pallets per hour, layout with transfers and turntables, accumulation needs, interfaces to palletiser or wrapper, environment (cold store, wash-down), and safety guarding.

02

Rate each module for load per metre and roller pitch

Interroll's PM 9711 chain-driven pallet roller conveyor is rated at a maximum of 1,000 kg/m or 1,200 kg per drive at 0.22 m/s, using 80 mm zinc-plated steel rollers with 3 mm walls at a pitch of 190.5 or 222.25 mm, a 0.07 kW in-roller pallet drive at 400 V and chain transmitted roller to roller so no chain tensioning is needed; conveying widths are 860, 1,060 and 1,295 mm. [2]

Its PM 9712 module instead drives a fixed number of idlers with a 24 V or 48 V RollerDrive through PolyVee belts, rated at 415 kg/m or 500 kg per drive at 0.2 or 0.28 m/s, with 60 mm rollers of 2 mm wall at a pitch of 90 to 120 mm. Both are specified for +5 to +45 °C non-condensing, with deep-freeze applications on request. [3]

Editorial calculation: a 1,200 mm Euro pallet conveyed lengthwise spans 1,200 / 190.5 ≈ 6.3 roller pitches, so at least 6 rollers are under it, or about 5 at 222.25 mm pitch. A fully rated 1,500 kg load on 1.2 m is 1,250 kg/m, above the 1,000 kg/m and 1,200 kg-per-drive ratings of the chain-driven module, and well above the 415 kg/m of the roller-drive module. [1] [2] [3] Use your heaviest real pallet, not the pallet's rated load, and check the drive rating as well as the per-metre rating.

03

Use drag chain where pallets will not ride on rollers

Roller modules need a pallet bottom that bridges the rollers. Hytrol, a US conveyor maker, describes its heavy-duty drag chain conveyors as dragging loads on chains, which suits items with uneven bottoms or loads that are difficult to move on roller conveyors. It lists load capacities up to 6,000 lbs, straight and curve versions, reversible options for bi-directional flow, handling of wet, dirty or oily products and use in high-temperature areas. Its transport models are the DC-62 and DC-63 and its accumulation models the DCEZD-62 and DCEZD-63, which use EZLogic accumulation control combining photo-electric sensing with discrete electronic logic without a PLC or pneumatic logic components. [4]

Editorial calculation: 6,000 lb is about 2,722 kg, which is above the 1,500 kg safe working load EPAL gives for a Euro pallet. [4] [1] Editorial note: Hytrol states its figure as a load capacity, not per metre, so ask the supplier whether it is per unit load, per section or per drive, and at what speed, before comparing it with the Interroll kg/m ratings. [4] [2]

04

End-of-line pallet lines, motorised-roller conveyors, and chain or roller systems with turntables

Listings include automated pallet conveyor lines and heavy-duty chain conveyors from an end-of-line packaging maker, pallet conveyors with motorised drive rollers, and pallet conveyor systems with dispensers, lifts and 90° turntable transfers. Ask each for the module load ratings, roller pitch and pallet types tested.

05

Rollers, in-roller or 24/48 V drive, chain or belt, frame, stops and turntables

Roller diameter and wall go with the module rating: 80 mm rollers with 3 mm walls on the 1,000 kg/m PM 9711, 60 mm with 2 mm walls on the 415 kg/m PM 9712. Transfers and turntables have no published detail in either datasheet. [2] [3]

06

Load per metre and per drive, pallet size, speed, voltage and width for a conveyor order

Load capacity is quoted two ways, per metre and per drive, and both limits apply; positioning accuracy, IP rating and module weight have no published value in the Interroll datasheets. [2] [3]

07

Send the pallet, load and layout data together

Paste it into your enquiry below or into an email to a maker, then replace every bracket.

Pallets: [types; sizes; direction; condition]
Load: [heaviest; lightest; height]
Throughput: [pallets per hour; accumulation]
Layout: [lengths; transfers; turntables; heights]
Interfaces: [palletiser; wrapper; store]
Environment: [temperature; wash-down; guarding]

See manufacturer records Send an enquiry through CNFX