Why stone/aggregate spread in sub-station yard and how its procedure of spreading in substation yard.

1) For reducing step potential and touch potential during short circuit in sub-station yard metal/ aggregate spreading is most important.

2) Reducing grass/shrubs /bushes growth in sub - station yard 

3) Improvement and Aesthetic view of sub station yard  

        Procedure of metal spreading in electric sub-station yard

1) Removing all exiting grass/ shrubs/bushes with it's roots in sub-station yard.

2) Collect existing old metal in sub-station yard.and keep in proper stacking 

3) Screening of existing metal with sieve and remove all dust, grease, plastic waste, roots of plant from old  metal also wherever necessary wash the existing metal and stack in proper.

4) After collection of metal in yard,filling uneven space with murum and keep yard proper level position. with help of level tube and leveling instrument. 

 

5) Now spread stone dust 25 mm to 50 mm thick as per yard condition.also compact the stone dust and fill the voids in murum and check level.

 

6) After spreading stone dust tarpaulin /plastic paper ( 150 to 200 GSM ) spread in yard with proper size.

                 

7) Spread 25mm to 40mm size metal /aggregate in two layer i.e 40 mm size one layer and 25 mm size  one layer total thickness is 65 mm.

8)After above layer Spread 12mm to 20mm size metal /aggregate in two layer i.e 20 mm size one layer and 12mm size  one layer total thickness is 35 mm.

9) Completion of all layer spray genetic herbicide on sub station yard .