Monday, 25 November 2024

Surveying and Levelling : CHAIN SURVEYING : Practical 1

         Chain surveying is the type of surveying in which only linear measurements are taken in the

field. This type of surveying is done for surveys of small extent to describe the boundaries of plot

of land to locate the existing features on them. 

         It is the method of surveying in which the area is divided into network of triangles and the

sides of the various triangles are measured directly in the field with a chain or a tape and no

angular measurements are taken. 

        Chains are the measuring instrument used in surveying formed by the 100 links of 4mm

galvanized mild steel wire. These links are joined by 3 circular or oval wire rings. These rings

provide the flexibility to the chains. 

        Every aspect of the life requires some measuring units. Measurements are used to do the

work precisely and accurately. Let it be from kitchen to office, everywhere measurements are

used. So as in engineering calculation or measurements holds a very greater role in construction

or surveying or any other aspect. 

        There are various units of measurements such as meters, centimeters, feets, inches, acre,

yards and the list goes on. Same as units there are various instrument used in the measurements

of any entity. One of the instruments used in measurement are chains. 



Parts of Chains used in Surveying

        The chain consists of many small parts used for handling or reading the measurements. 

        Every aspect of the life requires some measuring units. Measurements are used to do the

work precisely and accurately. Let it be from kitchen to office, everywhere measurements are

used. So as in engineering calculation or measurements holds a very greater role in construction

or surveying or any other aspect. 

        There are various units of measurements such as meters, centimeters, feets, inches, acre,

yards and the list goes on. Same as units there are various instrument used in the measurements

of any entity. One of the instruments used in measurement are chains. 

Parts of Chains used in Surveying

       The chain consists of many small parts used for handling or reading the measurements. 

o At the ends chain is provided with brass handle with swivel joint so that it can be easy to roll or

unroll the chain without twisting and knots. 

o At every 10th link is provided with a tally of one teeth, 20th link with a tally of two teeth and soon till 40th link. This is provided for the easy reading of measurements. 

o At the center of the chain is provided with a circular talley used for easy reading. 






Types of Chains used in Surveying

Depending upon the length of the chain, these are divide into following types, 

1. Metric chains 

2. Steel band or Band chain 

3. Gunter’s chain or surveyor’s chain 

4. Engineer’s chain 

5. Revenue chain 

A. Metric chains

Metric chains are the most commonly used chain in India. These types of chains comes in many

lengths such as 5, 10, 20 and 30 meters. Most commonly used is 20m chain. Tallies are provided

at every 2m of the chain for quick reading. Every link of this type of chain is 0.2m. The total

length of the chain is marked on the brass handle at the ends. 

B. Steel band or Band chain

These types of chain consist of a long narrow strip of steel of uniform width of 12 to 16 mm and

thickness of 0.3 to 0.6 mm. this chain is divides by brass studs at every 20cm or instead of brass

studs, band chain may have graduated engraving as centimeter. 


For easy use and workability band chains are wound on steel crosses or metal reels from which

they can be easily unrolled. These steel bands are available in 20m and 30m length and the width

of about 12-16mm. 

C. Gunter’s chain or surveyor’s chain

Gunter chain comes in standard 66ft. These chain consists of 100links, each link being 0.66ft or

7.92inches. The length 66ft is selected because it is convenient in land measurements. 

10 square Gunter’s chains = 1 Acre 

10 Gunter chains = 1 Furlong 

80 Gunter chains = 1 mile 

D. Engineer’s chain

This chain comes in 100ft length. It consist of 100 links each link being 1ft long. At every 10

links a brass ring or tags are provided for indication of 10 links. Readings are taken in feet and

decimal. 

E. Revenue Chain

The standard size of this type of chain is 33ft. The number of links are 16, each link being 

2  ft. This chain is commonly used in cadastral survey. 

PRINCIPLE OF CHAIN SURVEYING 

 The principal of chain surveying is to divide the area into a number of triangles of

suitable sides.  

 As a triangles is the only simple plane of geometrical figure which can be plotted from

the lengths of the three sides even if the angels are not known. 

 A network of triangles (triangulation) is preferred to in chain surveying.

 If the area to be surveyed is triangular in shape and if the lengths and sequence of its 

three sides are recorded the plane of area can be easily drawn. 



 

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