Spirit level

The spirit level ( spirit level or scale Maurer ) is a tester for horizontal or vertical orientation of an object and consists of a combined dragonfly which is aligned with the measuring surfaces.

Originally the term level refers to a broader dragonfly, whose version is not substantially greater than this level and has a flat side. Because of the shortness of such a spirit level you can use it to check only single objects such as beams or stone blocks in horizontal position. To composite structures, such as being able to check, for example a wall or pavement, this water balance ( mostly hardwood ) was placed on a longer bar. The slope of a channel or paving can be determined by measurement or by experience with the download point of the dragonfly. Usual is a marker ( Pars ) left and right at the Dragonfly, which corresponds to a deviation of usually one degree.

Spirit level, bricklayers balance ( as a tool of the mason ), refers to a test instrument with one or two dragonflies ( more are possible), in a 30-200 cm long aluminum profile construction profile, wasserunempfindlichem, sturdy hardwood, cast aluminum, plastic or etc. are embedded with one or two measurement surfaces. This measurement surfaces can be milled and coated. In two vials they are perpendicular to each other installed so that it is possible to check both the horizontal and the vertical. There are also water balances with three dragonflies; the third level ( gradient of sewage pipes ) or 45 ° tilt angle is then provided for the testing of the 2 ° tilt. Also rotatable dragonflies that can be adjusted according to a scale to certain values ​​are partially available.

Levels with a length of more than 200 cm are rare and are often mistakenly called straightedge. Water balances can be tried also for the function of a directional Scheits at the cost of pollution and wear and tear, but are clearly different from this object by the presence of dragonflies. The profile for real leveling bars is typically about twice to three times as high as that of a spirit level.

Nowadays almost exclusively Maurer different length scales are manufactured with two dragonflies and these generalized called water balance.

Special designs

While the water level is actually a tool that is only for the installation of individual components, such as stones, bricks, pipes, beams and not the building surveying over large distances, there are other forms as the cord level, post spirit level or laser level.

The line level is a dragonfly with ducted two eyes, so that you this, can knot as a string in a string framework. Because of sag of a horizontal line and the wind and vibration susceptibility, this can only serve as general orientation. The cord water balance should depend as closely as possible in the middle and the cord can be kept very tight.

The spirit level in mechanical engineering is a special form of the normal spirit level, since accuracies in the range of up to 0.01 mm are required to 1 m in length.

The laser level has a laser whose beam offset in height by a few centimeters, radiates parallel to the sole of the water balance. A laser unit comprising laser diode, control electronics and a lens for directing and focusing the laser beam is installed in the profile of a spirit level. The laser beam is then adjusted to the measuring surface of the water balance. The accuracy of the laser spirit level depends largely on the individual accuracy and the interaction of the individual components dragonfly, Level Profile and laser unit. Cheap laser levels from the discounters have often poorer accuracy (more than 1 mm / m) or do not even own a precision specifier. In addition, poorly built and inadequately aligned laser units or dragonflies. To transfer a height, for example, a reference marker, there are laser levels with leveling, which can be placed on a tripod or other firm position. While an ordinary hose water level or a leveling device may be used only for two, a worker can transfer a level with laser already using a spirit level. The range of the laser beam depends strongly on the ambient brightness and wavelength of the laser diode. Good laser levels have under normal site conditions a range of 30-40 m. For longer ranges and accuracies or a leveling rotary laser should be used.

Measurement accuracy

The measurement accuracy is specified on the level mostly in mm / m, but also in degrees and can be confirmed by an official Prüfamt by Siegel. It only indicates the maximum measurement error for measuring a distance with the length of the respective level, and not for the verification of two points with a distance of a few cm, and even for a measurement with intermediate points, for example at a distance of 1 m with a level with 40 cm length.

The measurement accuracy depends on the quality of the dragonfly, the mounting accuracy, on the aluminum profile / wood body and the accuracy of the setting edge. You can be poor due to improper handling (impacts, pressures, extreme temperatures and particularly at Levels of wood by moisture or even wet ), incorrect storage, lack of care or due to aging.

Typical measurement accuracies in the normal position in the new state:

• 0.057 °, which corresponds to 1 mm / m
• 0.0285 °, which corresponds to 0.5 mm / m

Printed with a simple scale, a tubular level are also used for the direct measurement of gradients.

The correct function and accuracy of a level can be easily checked by being placed in two ways, mirrored at the dragonfly, on a surface. They must show each the same. If they do not, they say that the spirit level "changes ". This approach tested a control measurement with oppositely attached meter is also recommended for important Horizontierungen.

History

Even the ancient Egyptians used to build the pyramid base plate the water by attracted a rectangular moat surrounding the proposed site and these filled with water. Everything was above the water line between the channels was removed. In this way, accuracy of 2 cm were achieved.

In ancient times, an isosceles triangle was used as a plumb level, has received a Lot ( plumb line ) suspended. The sinker is at the center of the base of the triangle when it is in balance.

In 1661 Melchisedec Thevenot developed a first usable level with encapsulated liquid. This had two banana-shaped capsules and was relatively complicated to use. Soon they went on to use alcohol instead of water to increase the frost resistance. The present building with a single, minimally curved capsule emerged in the 1920s.

Other tools with a similar function

• The spirit level (channel balance) is a simple geodetic measuring instrument.
• With knives and slope inclinometers any angle to the horizontal can be measured.
• With the hose leveling a certain height can also be transmitted horizontally without visual relationship.
• The circular level is used for coarse alignment in two dimensions, for example in the construction of the tripod optical instruments, and consists of a glass vessel, which is milled spherical round up and top center above has one or two marking circles.