Ingredients of Cement

INGREDIENT PERCENTAGE USE EXCESS LACK LIME 60-65 STRENGTH Unsound, disintegration of cement. Low strength, decrease setting time SILICA 17-25 STRENGTH High strength, increase setting time Low strength, decrease setting time ALUMINA 3-8 SETTING TIME Decrease setting time, decrease temperature of clinker Increase setting time IRON OXIDE 0.5-6 COLOUR Reddish color Low hardness MAGNESIA 0.1-3 COLOUR Yellowish color Low hardness GYPSUM 1-3 SETTING TIME Increases setting time Decreases setting time SULPHUR 1-3 SOUNDNESS Unsound Unsound ALKALI 0.1-1 Efflorescence

Read more

Differences between impulse and reaction turbine

IMPLUSE TURBINE REACTION TURBINE The potential energy of water is completely converted to kinetic energy while striking. The potential energy of water is partially converted to kinetic energy while striking. The pressure of jet striking is atmospheric. The pressure of jet striking is less than atmospheric It is not connected directly with pipe. It is connected directly with pipe. Ex: Pelton wheel turbine Ex: Francis Turbine Draft tube is not required. Draft tube is required in tailrace.

Read more

Difference between Flushing and Sluicing of Reservoir

Flushing Sluicing Flushing is done to remove sediment during high flood. Sluicing is done to remove sediment during plant operation. Intake structure aren’t operational during flushing as water level cannot be maintained. Intake structures can remain operational during sluicing as water level can be maintained. Outlet discharge is controlled by outlet structure. Outlet discharge is control by water level. Flushing has retrogressive erosion downstream. Retrogressive erosion doesn’t occur for sluicing. Flushing is done through bottom outlet. Sluicing outlet can be […]

Read more

Components of Tunnel

Chainage The length along the longitudinal direction of tunnel Crown The top portion of tunnel is crown. It can be circular,semi-circular or rectangular in shape. Side/Wall The side portion of tunnel. It is generally vertical. Bench The bottom part of tunnel left after the excavation of heading is said to be bench. Excavation of face in done in multiple step for large cross sectional area. Invert The lower portion of tunnel Portal The entrance of tunnel is portal. Heavy support […]

Read more