Technical Terms - Ceramic Tiles Manufacturing

These are the definitions given in ISO 13006 for ceramic tiles. 

Ceramic tiles

thin slabs made from clays and/or other inorganic raw materials, generally used as coverings for floors and walls, usually shaped by extruding (A) or pressing (B) at room temperature but may be formed by other processes (C), then dried and subsequently fired at temperatures sufficient to develop the required properties; tiles can be glazed (GL) or unglazed (UGL) and are incombustible and unaffected by light

Vitrified covering which is impermeable

Engobed surface

Clay-based covering with a matt finish which can be permeable or impermeable

NOTE          : A tile with an engobed surface is regarded as an unglazed tile.

Polished surface

Surface of an unglazed tile which has been given a glossy finish by mechanical polishing as the last stage of manufacture

Extruded tiles

[Designated as A]

Tiles whose body is shaped in the plastic state in an extruder, the column obtained being cut into tiles of pre- determined dimension

NOTE 1: This International Standard classifies extruded tiles as “precision” or “natural”. The classification is dependent upon the different technical characteristics as listed in the individual product standards.

NOTE 2: Traditional  terms  used  for  extruded  products  are  “split  tiles”  and  “quarry  tiles”  They   commonly indicate double-extruded and single-extruded tiles respectively. The term “quarry tiles” only refers to extruded tiles with a water absorption not exceeding 6 %.

Dry-pressed tiles

[Designated as B]

Tiles formed from a finely milled body mixture and shaped in moulds at high pressure

Tiles made by other processes

[Designated as C]

Tiles made by other than the normal commercial processes, i.e. extruded or dry-pressed

NOTE          : These tiles are not covered in this International Standard.

Spacer lugs

projections which are located along certain edges of tiles so that when two tiles are placed together, in line, the lugs on adjacent edges separate the tiles by a distance not less than the specified width of the joint

NOTE 1: Lugs are positioned so that the joint between the tiles may be filled with grout without the lugs remaining exposed. NOTE 2 Dry-pressed tiles may be made with other spacer lug systems and, in such cases, the manufacturer’s work size applies.

Water absorption

[Symbol E]

Percentage of water by mass, measured in accordance with ISO 10454-3

Description of sizes

NOTE          : These are only defined for rectangular tiles. If the sizes of non-rectangular tiles are required, they are defined by the smallest rectangle into which they will fit.

Nominal size

Size used to describe the product

Work size [symbol W]

Size of a tile specified for manufacturing to which the actual size has to conform within specified permissible deviations

NOTE: This is specified by the dimensions length, width and thickness.

Actual size

Size obtained by measuring the face of the tile in accordance with ISO 10545-2

Coordinating size [symbol C]

Work size plus the joint width

Modular size

tiles and sizes based on module M, 2 M, 3 M and 5 M and also their multiples or subdivisions, except for tiles with a surface area of less than 9 000 mm2