A gravity roller conveyor is often the least complicated part of a warehouse line: no motor, no control panel and no power supply. It also causes a surprising number of flow problems when the slope, roller pitch or load base is wrong. Here is what to check before specifying one.
How a gravity roller conveyor moves a load
There is no drive. Rollers spin freely in a frame, and the load moves because the frame is set at a slight fall or because an operator gives it a push. Starting friction, bearing condition and the flatness of the carton base all affect whether a box keeps rolling or stops halfway along a run.
This makes gravity sections well suited to cartons, totes, crates and pallets with a firm, flat underside. Bags, soft packages, small loose parts and items with feet or rails need a continuous belt surface instead.
Roller conveyor belt: a search term worth clarifying
The phrase roller conveyor belt is used for three different things online. It can mean a belt conveyor, where product rides on a continuous belt; it can mean a belt-driven roller conveyor, where O-rings or a line shaft turn the rollers that still support the load; or it can refer to a spare belt used inside a powered roller drive.
If the goods have a soft or irregular base, a belt conveyor is the technology to look for. If the goods are rigid cartons but need controlled movement, a belt-driven powered roller line is the usual answer. Stating the load and the base condition in an enquiry avoids a quotation built around the wrong interpretation.
Slope, pitch and frame: three layout rules
Pitch follows the smallest load: keep at least three rollers under it at all times, and reduce the gap for short or light cartons. Slope is set by trial with a loaded carton, since a fall that is too steep lets heavy boxes accelerate into the next section while a shallow fall leaves light boxes stationary.
Effective width is normally the widest load plus a small clearance each side, with adjustable guides where sizes vary. Check working height at both ends, support leg spacing and whether castors or adjustable feet are needed. On long runs, break the line into powered and gravity zones instead of increasing the fall.
Where gravity sections fit, and where they do not
Gravity lines work well as buffer zones, short transfers, loading bay links, temporary or seasonal lines, and flexible expandable sections that can be moved and reshaped. They are quiet, simple to extend and need no electrical installation.
They are a poor fit where flow must be timed, where cartons need zero-pressure accumulation, where the line climbs, or where a scanner or sealer needs a consistent presentation speed. A common mixed layout uses powered zones at controlled points and gravity sections as low-cost buffers between them.
A buying checklist before you order
Confirm the full range of load sizes and weights, the base material, items per hour, straight length, curve or telescopic sections, working height, available fall, floor condition, wet or washdown exposure, and whether the frame must be mobile. Ask for roller diameter, pitch, tube material, bearing type and frame finish in writing.
For export orders, also confirm packing method, section labelling, assembly instructions and a spare roller set matched to the frame width. JINDA supplies gravity sections, powered sections and replacement rollers built to the same dimensions, so a later extension matches the original line.
Browse the roller conveyor range or send a sketch of your layout for a configuration review.
