What Is Boiler Mounting?

Boiler mountings are mechanical devices that are considered necessary to operate the boiler smoothly & safely, which are usually mounted on surfaces of the boilers. These are the parts of the system that are mounted on the boiler’s own body for protection of the boiler and for complete control of the steam generation cycle. Machinery protects the boiler from damage to itself due to extremely high pressure, steam backflow, vacuum shell collapse, irregular steam pressure, low water, pumping backflow, and dry running.

1. Main Steam Stop Valve

It is usually applied to the highest part of the shell through the flanges. To control the flow of steams from the boilers to the main steam pipe. The steam produced in the boilers is provided by this valve to the ship’s system to completely shut off the steam when required. It is typically a non-return valve type installed directly at the steam location of the boiler shells. The body is made of cast irons, & the valve seat is made of gunmetal.

2. Auxiliary Steam Stop Valve

A separate steam line provided by the boilers for the small auxiliary system is supplied to most steam systems on ships through this valve. The valve is small in size and is generally a non-return type.

3. Safety Valve

Location It is attached to boiler mounting steam chests. Function To blow off steam to prevent explosions when the steam pressure inside the boiler exceeds the working pressure. Commonly used safety valves are spring-loaded safety valves. In case of unsafe excess pressures inside the boilers, a safety valve is used to release the excess pressure. Before installation, the lifting pressure of the valve is set & locked in the presence of surveyors so that it does not change later. In generals, safety valves are fitted in pairs.

4. Scum Blowdown Valves

Location: It is mounted in the crown plate of a boiler mounting furnace or firebox.

Functions: To extinguish a fire in a boiler furnace when the water level in the boiler falls to an unsafe limit, and thus the explosion caused by overheating of the furnace plate is avoided.

A shallow dish types systems equipped at ordinary water level enables floating impurities, oil foaming, etc., to float from the surface of the water.

5. Salinometer valve

Location: The sampling water cock system is usually equipped with a cooler in order so that water samples can be collected at any time for testing the feed water.

Functions: To test the salinity of the water.

6. Whistle Valve

If a steam whistle is applied to the ship, the steam is supplied directly from the boiler, in the form of a small non-return valve known as the whistle valve.

7. Soot Blower

Function: Required for soot blowing & pipe surface combustion products. It is operated by steams or compressed air.

8. Automatic Feed Water Regulator

Location: A device that is important and fit into the feed line

Functions: Automatic feed water regulator is one of the important boiler mountings to ensure a proper level of water under all load conditions. In boilers with high evaporation rates, several feed element water control systems are used.

9. Manhole

Function: The boiler consists of several manhole gates which enable inspection, cleaning, and maintenance of boiler tubes and internal components by the crew.

Location: Usually fitted in a gate steam drum and a water drum.

10. Mud box

Function: Earthen cans are used in boilers to collect mud (dirty impurities) from water drums.

Location: Fitted underwater drum.

11. TDS Sensor and Sample

Functions Most modern boilers are now equipped with this system for continuous monitoring of total dissolved solids in the boiler water. The sensor compares the actual value to the setpoint, and if the value is higher, then an audio-visual alarm is given. A manual blowdown introduces fresh feedwater into the system to reduce total dissolved solids content.

12. Water Level Gauge Glass

Location: This fitting can be seen in front of the boiler.

Function: This boiler mounting is fitted to indicate the water level inside the boiler. Gauge glasses are also fitted in pairs to manually monitor the water level inside the boiler tank. The construction of gauge glass is chosen based on the pressure of the boiler.

13. Air vent cock

Location: It is fitted in valve headers, boiler drums, etc.

Function: To protect the boiler from bursting when depressurized or when steam pressure increases internally.

The word explosion is the opposite of explosion. In this situation, the pressure inside the boiler will be sufficiently reduced by atmospheric pressure to prevent the shell from bending inward; this boiler mounting is required.

14. Feed Check Valves and Controls

Location: It is fitted in the shell slightly below the normal water level of the boiler. It is a non-return valve fitted into a screw spindle to control the lift.

Functions: To regulate the water supply, which is pumped into the boiler by a feed pump.

This valve controls the supply of steams as required & is installed after the stop valves in both main and aux steam lines. They are non-return valves that have visible signs of open and near position.

15. Pressure Gauge Connection

Location: It is fixed on the fronts of the boilers.

Functions: To measure the pressure of steam inside a steam boiler.

This pressure gauge can be installed in superheaters, boiler drums, and wherever necessary to read pressure readings. Commonly used pressure gauges are the Bourdon type.

16. Blowdown Valve

Location: Blowdown is an important boiler mounting, which is located below the boiler.

Work: To evacuate the boiler whenever necessary and to remove soil, scale, or sediment deposited on the bottom of the boiler.

It is used when the chloride level becomes too high for thorough cleaning of the boiler or for water treatment of the boiler.

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