Glossary – our knowledge from A to Z

A macrosection examination is carried out by grinding the workpiece specimen to a fine finish and then applying an etching solution to the surface. This reveals coarse structures, e.g. number and arrangement of weld runs in a weld seam, also defects, hardness zones in case-hardened parts or cast structures.

Metal active gas welding is a process in which an electric arc burns within a protective shield formed by active, incombustible gases. The electrode is fed from a reel; the torch can be guided manually or fully automatically by a welding robot. This type of welding is used for unalloyed steels.

A test used to establish defects on or near the surface of magnetic materials, primarily ferritic steel and ferritic iron.

This is used to hold two metal pieces at a certain angle so that they can be welded together, for example.

This is an iron ore with a high iron content. The iron and oxygen atoms are firmly bonded together in magnetite.

This is a control and coordination concept that supports the management and accountable positions during the targeted influencing of existing operational processes. The task is to monitor the economic efficiency in the company on behalf of the management but not to guarantee this.

This is the monitoring and assessment of deviations and changes and their economic consequences for the purpose of determining and asserting claims. In project business this element is found on both the contractual and client sides.

A chemical element that has been used in the production of glass since ancient times. Manganese can be used to increase the strength and toughness of a material.

This is a chemical compound of manganese and oxygen. During the production of glass manganese oxide is used to remove the yellow-green tinge caused by small quantities of iron silicates in the raw materials.

A pitched roof form with two different pitches on each side and the lower surfaces at a much steeper angle than the upper ones. This form allows the roof space to be better used. (US: gambrel roof)

A ferromagnetic metastable structure in metals which is formed from the original microstructure by a cooperative diffusionless, athermal, shear transformation.

A type of access platform of variable width for transporting persons and materials up to and also working at heights of about max. 60 m.

A special type of rolled glass with small embossed squares.

A special type of rolled glass with embossed longitudinal grooves.

A special type of rolled glass with small embossed elongated rectangles.

Material fatigue is the slow progression of a damaging process in a material exposed to environmental influences such as alternating mechanical loads, fluctuating temperatures, possibly the effect of a corrosive medium as well.

In this type of ventilation motor-driven fans with thermal cut-outs control the removal of excess heat. They draw the warm air to the highest point and then expel it. Cooler air enters at the base to replace this. Mesh screens over the inlets and outlets prevent the entry of insects and small animals.

This is a separating layer. We distinguish between impermeable, semi-permeable (or selectively permeable) membranes, and those that are permeable in one direction only (unidirectional) or in all directions (omnipermeable).

A technology employed for thin, lightweight plate and shell structures. The theory is based on the assumption that bending must be ruled out in such a thin structure because it causes unacceptable deformations. The structure can accommodate only shear stresses and direct tension or compression. In the case of a shell loaded in compression, or a tent structure loaded exclusively in tension, bending is eliminated by designing a suitable perimeter construction. These – in relation to their surface area – very thin membranes avoid such stresses by deforming or by dissipating any induced prestress.

This anchor benefits from a clamping or wedging effect that holds it in the drilled hole. This effect is achieved by driving a cone into an expanding sleeve, which forces the parts of the sleeve apart to make contact with the sides of the hole. Metal anchors have a higher load-carrying capacity and are more secure than those made from plastic because they can transfer considerably higher expansion forces to the sides of the hole and hence the material of the wall.

This type of lamp with a halogen filling belongs to the group of discharge lamps. The primary applications are the illumination of goods (“shopping light”), trade fair halls, building floodlighting, stadiums, production buildings and warehouses.

Louvres can be used to influence the distribution of light and shade within a building. Metal louvres allow the amount of daylight entering the interior to be regulated.

A three-ply composite panel with vibration-attenuating properties.

This is an unalloyed tempering steel type in which the quantities of, for example, vanadium and/or niobium or titanium added lie below the limiting values for alloyed steels.

Multi-pane insulating glass, which consists of at least two panes of glass that are separated by at least one cavity formed by the spacer.

Abbreviation for metal inert gas welding.

An aluminium cover strip with perforated and serrated fixing legs and an elastic seal made from synthetic rubber.

A residue or layer of oxide that forms on the surface of steel during annealing, rolling or forging. Mill scale consists of several layers of oxide with different chemical compositions.

A production line consisting of one or more roll stands and all the associated feeding, handling and cutting plant.

This metalworking process is used to produce flat surfaces or contours. The milling cutter exits the workpiece and the cooling after every revolution and the cutting action of the cutting teeth. This intermittent cutting action leads to fluctuating cutting forces and temperatures at the cutting teeth.

These are inorganic fibres with a natural or artificial origin. Mineral fibres can frequently be used for textile applications, e.g. for mineral wool or for weaving asbestos.

This term is frequently used for watch crystals in order to differentiate ordinary glass from the much softer synthetic glass materials and the very much harder synthetic sapphire.

This is an incombustible insulating material made from either glass wool or rock wool.

A small mobile crane for internal and external deployment with non-damaging outriggers and rubber tracks. Such cranes are used on muddy ground, steep slopes and wherever space is tight (e.g. in interiors) or where a low plant weight (e.g. on marble floors) is essential.

This is a surface that reflects light and therefore shows an image of anything in front of the mirror. A reflection in a flat mirror reproduces both lengths and angles accurately, but the image is handed, i.e. left and right are reversed. Traditional mirrors are these days made from sheet glass coated with aluminium.

A type of edge working used on glass and mirrors, especially thick materials.

The two parts to be joined at the corner are cut at an angle.

A glass edge sloped at the appropriate angle. Mitres can be honed or polished.

This output wave form simulates a sine wave and consists of a flat plateau of positive voltage which drops abruptly to zero briefly, then drops again to a flat plateau of negative voltage, then back to zero briefly before returning to the positive voltage. It is sometimes erroneously called a square wave.

The division of a whole unit into regular parts known as modules.

An optical phenomenon that can occur in the form of a wavy, rippled or circular pattern under certain lighting conditions. The Moiré effect can also occur when patterned panes of glass are laid on top of each other and the patterns are not concurrent.

The important aspects in moisture control are to protect the window against the infiltration of rain from the outside and to prevent condensation on the inside and at the junctions with the adjoining components.

Considerable quantities of water vapour are transported in air flowing from warm to cold zones as well as by way of diffusion. This is particularly noticeable at joints and gaps, where water can collect at the colder places.

This is a desiccant used in the spacers of insulating glass which ensures dehumidification of the cavity between the panes. A molecular sieve has a limited moisture absorption capacity and so the lifetime of an insulating glass unit is finite. Also known as drying agent.

A chemical element. A molybdenum content of 0.2% improves the through-hardening of steels and at the same time prevents temper embrittlement. Owing to its microstructure-stabilising effect at high temperatures, molybdenum is used in materials designed for high operating temperatures.

Single homogeneous pane configuration (in contrast to a composite pane configuration such as laminated safety glass).

A roof form with only one sloping surface. The lower edge is the eaves, the upper edge the ridge. Also known as lean-to roof.

This type of glass is produced by passing the glass mass between two rollers while it is still fluid. These emboss a high-precision geometrical or other motif in the glass.

One application of a moulding is to separate various levels or transitions between materials, e.g. junction between floor and wall, soffit and wall.

In buildings and structures a movement joint is a gap between two components or materials. The purpose of a movement joint is to interrupt components and therefore prevent stress-induced cracking.

A silicone-free synthetic material that can guarantee a hydrophilic function for the entire glass surface right up to the sealed joint. MS polymers consist of polypropylene oxide with silane end-groups.

In this type of construction several bays of the façade, one above the other, are not separated by seals but instead the post and rails are interconnected via open rebates at the sides. Any water that collects drains from the rails to the posts and to the outside at the base of each post.

This type of glass complies with thermal insulation, sound insulation and also anti-intruder requirements.

This is a type of insulating glass that consists of two or three panes. There is a hermetically sealed cavity between each pair of panes which is filled with a noble gas such as argon or krypton.

Term occasionally used for laminated safety glass.