Summary
A ball transfer unit lets loads move in any direction with no power.
Learn how BTUs work, their types and uses in this complete guide.
A ball transfer unit (BTU) is a load-bearing device, fitted into a surface, that lets heavy objects be moved smoothly in any horizontal direction with minimal effort and no power. A large load ball sits on a bed of smaller support balls inside a housing, so an item placed on top can be pushed forwards, sideways, diagonally or rotated on the spot. Alwayse invented the ball transfer unit in Birmingham and today manufactures one of the world’s widest ranges — 150+ standard variants handling loads from a few kilograms up to 12,000kg.
If you have ever pushed a heavy box across a free-running surface in a warehouse, an airport cargo terminal or a factory assembly line, you have almost certainly used ball transfer units. This guide explains exactly what they are, how they work, the main types and materials, and where they are used — and links through to the right product range at each step.
How a ball transfer unit works
A ball transfer unit works on a simple principle: a single large load ball rests on a bed of many smaller support balls held inside a housing. The load ball can rotate freely in every direction because the support balls beneath it roll with it, so the friction of moving an object is reduced to a fraction of dragging it across a flat surface.
Because the movement is omnidirectional, a BTU has no fixed direction of travel — unlike a roller, which only turns on one axis. This is the defining advantage: an operator can guide a load to an exact position, change direction instantly, and rotate it in place, all by hand. No motor, electricity or hydraulics is required, which is why ball transfer units carry zero running cost and need no electrical infrastructure.
The main parts of a ball transfer unit
Every Alwayse ball transfer unit is built from the same core components, machined and assembled in Birmingham:
- Load ball — the large ball that contacts the item being moved. Available in carbon chrome steel, stainless steel or nylon depending on the application.
- Support balls — the bed of smaller balls the load ball rotates on, distributing the load and enabling smooth rotation.
- Housing — the body that holds everything together and provides the fixing method (flange, threaded stem, base plate and so on).
- Seal — a felt or synthetic wiper that keeps dust, swarf and moisture out of the bearing, protecting performance and service life.
Types of ball transfer unit
Alwayse organises its range by load capacity, mapped to three clear tiers so you can size a unit quickly:
| Load tier |
Per-unit capacity |
Typical use |
Browse |
| Light load |
0–100 kg |
Packaging, retail display, electronics, glass handling |
Light load |
| Medium load |
101–249 kg |
General logistics, packing stations, conveyor junctions |
Medium load |
| Heavy load |
250 kg + |
Air cargo, steel and plate handling, heavy assembly |
Heavy load |
Beyond load rating, specialist types include pneumatic pop-up units for switchable live/dead workstations, spring-loaded units for shock and impact, and miniature units for precision and cleanroom work. If no standard unit fits, Alwayse also designs custom ball transfer units.
Materials: steel, stainless and nylon
The load ball material is chosen for the environment and the surface being handled. Carbon chrome steel is the hard-wearing default for dry indoor use; stainless steel resists corrosion in wet, hygienic or outdoor settings; and nylon is soft and non-marking for delicate surfaces such as glass. The trade-offs are covered in full in our guide to ball transfer unit materials.
Mounting and fixing styles
How a unit is fixed determines installation, maintenance access and the finished surface. The five main styles are flanged, threaded stem, drop-in (press-fit), clamped and base fixing. Each is compared in our guide to ball transfer unit mounting types, with the matching fixing-method filters on the product hub.
Where ball transfer units are used
Ball transfer units appear in almost every industry that moves goods. Alwayse exports to more than 75 countries, supplying sectors from air cargo and logistics to glass processing, food and beverage and automotive and lean manufacturing. Common applications include ball transfer tables, air cargo ball decks, conveyor transfer points, machine tables and assembly workstations.
Why choose ball transfer units
- Omnidirectional movement — guide and rotate loads in any direction, not just one axis.
- No power required — zero energy cost, no motors, no electrical infrastructure, lower carbon footprint.
- Reduced manual handling injury — operators push instead of lift, cutting musculoskeletal risk.
- Long service life — precision-machined, lubricated-for-life units, 100% tested before dispatch.
- Proven at scale — handling up to 12,000kg, in service across 75+ countries since 1941.
Not sure which unit you need? Use the ball transfer unit search tool or the Brief Builder, or contact the Alwayse technical team on +44 (0)121 380 4700.
Frequently asked questions
What is a ball transfer unit used for?
A ball transfer unit is used to move heavy or awkward items smoothly in any direction across a surface, by hand and without power. They are fitted into ball tables, air cargo ball decks, conveyor transfer points, machine tables and assembly workstations across manufacturing and logistics.
How much weight can a ball transfer unit hold?
It depends on the unit. Alwayse ball transfer units span three tiers — light load (0–100kg), medium load (101–249kg) and heavy load (250kg and above) — with the heaviest-duty solutions handling loads up to 12,000kg when correctly specified.
Do ball transfer units need power?
No. Ball transfer units are entirely passive. Loads are moved by manual pushing or by gravity on an incline, so there is no electricity, no motor and no running cost.
Who invented the ball transfer unit?
Alwayse Engineering invented the ball transfer unit in Birmingham in 1941. The ‘all-ways’ directional movement gave the company its name, and Alwayse has manufactured BTUs in Birmingham ever since.