What is a shelf company

Shelf glossary - technical terms for all types of storage shelves

Reading time: 5 minutes

Various types of storage racks such as heavy-duty racks, pallet racks and others are available for warehouse equipment and operating facilities for intralogistics as well as office, lounge and workshop rooms. In our glossary, we explain important specialist terms and technical terms that apply to all shelf types equally.


Unwinding mandrel

According to DGUV rule 108-007, stored round material must be secured against rolling out. A roll-off mandrel divides the cantilever arms of a cantilever rack.

Aisle width

In order to prevent accidents caused by collisions with industrial trucks, a certain safety distance from the storage rack must be maintained when maneuvering with forklifts or pallet trucks. The aisle width for forklifts and pallet trucks is also calculated from this.

Cultivation field

An add-on field can only be added to a basic field or an existing shelf. For each row of shelves, a basic field is required first, to which any number of add-on shelves can be added. It consists of a frame and several shelves or storage trays. In contrast to the basic field, it cannot be used individually.

Leaning ladder

This is a one-piece or two-piece step or rung ladder that can be placed on the shelf.


Storage racks are stiffened for a secure stand. The stiffening with tension crosses occurs mainly in shelving racks. The diagonal reinforcement with longitudinal bars, on the other hand, is mainly used for pallet racks.


The clasps (or hooks) are used for stiffening with longitudinal bars for hanging in the support profiles of the shelf.


Double sided

Double-sided shelves are free-standing and can be operated from both sides. The shelves lie on longitudinal bars that reinforce the shelf.

Double line

Double-row shelves are also free-standing and form a static unit thanks to the back-to-back assembly.


A spacer is used when assembling pallet racks to achieve an even distance between the racks.

Push-through protection

The safety device prevents stored goods from being pushed through too far when loading double-row shelves. Push-through locks are also used to secure single-row shelves.



Levels are the storage areas on top of each other per shelf field. In the case of pallet racks, some also include the floor level as storage space. At Jungheinrich PROFISHOP, however, only the tie-bar levels are counted for levels; the floor level does not count as a storage level in the technical data.

Corner bracket

Corner angles are used to stabilize and stiffen shelving systems in depth and width. The corner brackets are used for shelves with both screw and plug-in systems.

Single shelf line

In contrast to double-sided shelves, single shelf rows can only be operated from one side. They are often stiffened with cross braces and are ideal for wall installation.



Shelves serve as load handling devices for stored goods of all shapes and sizes and can therefore be used to store general cargo.

Compartment height

The compartment height is the distance between the floor and the top of the first shelf or between the top of one compartment and the top of the next shelf. The compartment height is also known as the buckling length. The compartment height has a significant influence on the bay load. The clear compartment height, on the other hand, is the compartment height from the top edge to the bottom edge of the next spar and is the height that is available in the compartment for storage.

Compartment load

The compartment load describes the maximum load-bearing capacity of the individual shelf compartment with suitable distribution of the weight on the shelf. If the compartment load is exceeded, individual shelves can collapse. The compartment load must be clearly visible on the shelf.

Field load

The bay load denotes the maximum weight that the entire rack can carry. The sum of the compartment loads on top of each other must not exceed the permissible bay load. The bay load is also influenced by the compartment height. The bay load can also be significantly less than the sum of the possible compartment loads - depending on the material and processing of the shelving racks. If the total bay load is exceeded, there is a risk of the entire shelf collapsing. The bay load must also be marked on the shelf.


Basic field

A shelf base field (or "base shelf") is always required at the beginning of a shelf row. It consists of 2 frames and at least one shelf. In contrast to the cultivation field, it can be used individually.



In the case of pallet racks, the front and rear bars form the storage level on which the pallets are placed. Depending on the compartment and bay load of the shelves, the bars can vary in strength and load-bearing capacity. With supports made of steel or wood, piece goods can also be stored on the spar construction without pallets.


Buckling length

See compartment height

Picking tray

A picking tray complements shelves with sloping shelves or roller strips. Individual goods removed from the shelf can be put together as required on the shelf.


Cantilever arms are the eponymous arms of cantilever racks. Round or very long goods such as strips of wood or pipes are stored on them and secured against rolling away with an unwinding mandrel. Depending on the shelf model, cantilever arms are permanently welded or screwed to the stand. In the latter case, the cantilever arms are adjustable in height.

Cross brace

Cross struts are used to diagonally stiffen storage racks.


Longitudinal bar

Longitudinal bars stiffen plug-in shelving diagonally and are mainly used to stabilize shelving units. They each have a clasp on the right and left and are used in plug-in shelving systems at certain intervals. They are used in shelving to enable removal from both sides, as the cross bracing is not required.



Storage racks can be assembled in a number of ways. Screw systems in which the individual shelf parts are mounted using screw connections are common. Shelf assembly using plug-in connections is particularly quick and easy. Many types of shelves are built with a combination of screw and plug connections. For wall shelves or storage shelves with certain shelf heights and load types, a wall or floor screw connection is also required.



In factories, pallets are used as both transport and storage space. They can be used to load and unload stored goods on forklifts or pallet trucks and store them in pallet racks.


Ram protection

If shelves are loaded or unloaded with forklift trucks, they must be provided with ram protection (also called "collision protection") in the corner areas and passages. The collision protection must be at least 300mm high and be able to absorb an energy of 400 Nm.

Shelving systems

The term shelving systems refers to a storage shelf that can be individually extended both in height and width by means of add-ons. The extension takes place through cultivation fields.

Shelf inspection / shelf inspection

Regular inspections by specialist staff are required for some types of shelving. When inspecting shelves that are subject to inspection, material damage, violations of labeling requirements or other defects can be identified and eliminated. The shelf inspection must also be documented.

Roller rails

Individual stored goods can be transported easily using roller strips in storage racks.


Screw / plug system

With this system, the stand construction of the shelf is mounted using screw connections. The individual shelves are then supplemented using a plug-in assembly.

Screw system

The shelves of the shelf are also screwed on here. This is done using angle profiles. Corner brackets are used for reinforcement.

Locking pin

The bars in pallet racks are secured with locking pins so that they cannot be accidentally lifted out when loading and unloading the rack.

Connector system

Shelves in the plug-in system consist of T-profile frames. The shelves are attached to the frame using shelf supports and their height can be varied at any time without the use of tools. This means that they can be flexibly adapted to the stored goods. The special folding of the T-profiles also allows a particularly high level of stability and load-bearing capacity.

Column profile

Column profiles are vertical supporting elements that are connected to a supporting frame with tension crosses or C-profiles. In the case of shelves with a screw system, the support profiles are erected with angle and corner profiles to form a load-bearing frame in which the shelves come to lie.


T-profile frame

See connector system

Load capacity

See compartment load and bay load


Cross members stiffen pallet and shelf racks horizontally and also serve as a support surface for shelves. Depending on the equipment, traverses are hung in the plug-in system using clasps or screwed to the support profile using a screw system.



Beams are used to increase the stability and load-bearing capacity of shelves and to prevent bending and breaking under high loads.


Angle support

Angle supports enable the safe storage of lattice box pallets. The feet of the lattice boxes are guided over the supports and placed on the rack rails.

Angle profiles

See screw system

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