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Step-by-Step Guide to Dumpy Level Surveying

The dumpy level is an instrument of surveying which has been used for the level survey for measuring the heights of the objects. The dumpy level surveying has been set to an accurate horizontal plane. This helps to allow the precise measurement of the heights that have to be taken while using the measuring staff. The measurement staff is similar to the ruler, which has been set upon the point that the surveyor wants to measure. Most of the measurement staff has been extended to around 5 meters, which allows a good range of height for measurement. The dumpy level surveying has been used on different construction sites, archeological digs, engineering projects and other fields.

Equipment required for Dumpy Level Surveying

Various equipment has been required for the operations of the Dumpy Level Surveying, which are as follows:

Telescope

Telescope has been fixed to the vertical spindle of the dumpy level which helps to allow the rotation along with the vertical spindle. Different parts of the telescope are used for different purposes in the dumpy level surveying. The eye pieces have been used to observe the distant objects. This part contains a magnifying glass which helps to take accurate readings. The objective lens has been located at the other end of the telescope which contains concave and convex lenses for providing an inverted image. Diaphragm has been positioned in the front of the eye piece which contains cross hairs for getting the precise observations. The focusing screw of the telescope helps to adjust the focus the image and the ray shade of the telescope helps to prevent the sunlight or other types of light rays which disturbs the line of the sight.

Compass

The compass helps to determine the magnetic bearing of the line along with a pointer set to zero facing the north line.

Bubble Tubes

Two bubble tubes are present in the dumpy level surveying which helps to check the level of instruments.

Vertical Spindle

This equipment of the dumpy level surveying has been located at the center of the instrument which helps to allow the telescope to rotate horizontally.

Tribrach

This equipment is parallel to the levelling head, which helps to ensure the horizontal level of the instrument.

Foot Screws

The foot screw helps to regulate the position of the tribrach as well as helps to allow the instrument to be levelled through adjusting the tribrach plate.

Leveling Head

This equipment contains two parallel triangular plates along with grooves which help to support the leveling.

Tripod

This equipment of the dumpy level surveying helps to support the entire levelling instrument along with its three adjustable legs.

Using procedures of Dumpy Level Surveying

Three processes have been involved in using the dumpy level surveying, which are as follows:

Setting up the instrument of the dumpy level

The instrument has been fixed to the tripod stand with the help of the cramp screw. After that, the legs of the tripod have spread and the instrument has been positioned at the convenient height which helps to initiate the levelling process. This process begins by setting the two legs of the tripod in the ground at a point and fixing the bubble in the bubble tube through adjusting the third leg of the tripod.

The levelling procedures

Foot screws or levelig screws has been inovolved in leveling the instruemnts. In this conext, telescope has been aligned parallel to any leveling screws and centering the bubbles within the bubble tube. After that, the telescope has rotates 90 degree and the third screws has been adjusted until the bubble centers. This procedure has been repeated until the bubble consistently stays at the middle.

Focusing the telescope used in the dumpy level

In this process, the focus of the telescope has been achieved by adjusting the focusing screw and the eyepiece. The eyepiece has been aligned until the crosshair of the diaphragm has been visible clearly. A white paper can be used for eliminating the parallax error which helps to achieve a sharp vision of the crosshairs.

The focusing screws has been also adjusted to achieve a clear image of the staff or objective. While the crosshair bisects the objective along with a clear vision, the focusing process has been completed. After performing these adjustments, the telescope has been rotated towards the line of the staff which helps to take level measurements at different levels.

Applications of Dumpy Level Surveying

There are numerous applications of the Dumpy Level Surveying in the construction site, which are as follows:

• The Dumpy Level Surveying has been used for determining the elevation differences of different points in the surveying procedure.
• The Dumpy Level Surveying also helps to measure the distances between the points of the same elevations.
• The Dumpy Level Surveying has been used by the surveyors for establishing a level surface on the land, which has been used for various applications.
• The Dumpy Level Surveying has been widely used in the civil engineering projects for the development of roads, railways, pipelines, and drainage structures.
• The fixed telescope along with the vertical spindle of the Dumpy Level Surveying helps to allow for the efficient horizontal rotation in the meantime of the surveying tasks.
• The Dumpy Level Surveying along with its integrated compass, helps to determine the magnetic bearing of the surveyed lines.
• The tribrach plates and foot screws of the Dumpy Level Surveying helps to allow the precise levelling of the instrument on the varied terrains.
• The bubble tubes of the Dumpy Level Surveying also help to ensure that the dumpy level has been levelled properly for the accurate measurement of the survey.
• The telescope used in the Dumpy Level Surveying also helps to observe the distant objects along with the line of sight.