Dead weight safety valves are safety valves used to release the excess steam when the pressure of steam inside the boiler exceeds the rated pressure. This valve consists of a vertical cast iron pipe through which steam pressure acts. The steam pressure of the valve acts in the upward direction and is balanced by the force of the dead weights. The total dead weights of the valve include the sum of the weights like, weight of the valve, weight of weight carrier and cover plate. The merits of this valve are its simplicity in design, satisfactory performance during operation as well as it can be easily tampered from the pressure adjustment view-point. These dead weight safety valves are used for low pressure, low capacity, stationary boilers of Cornish and Lancashire types.