What is excess air in boiler?
There is a theoretical amount of fresh air that when mixed with a fixed amount of fuel, and burnt will result in perfect combustion. In this situation all of the fuel will have been properly burnt and all of the oxygen in the air will have been consumed.
How do I reduce the air in my boiler?
Boilers often operate at excess air levels higher than the optimum. Periodically monitor flue gas composition and tune your boilers to maintain excess air at optimum levels.
How does a fired heater work?
Fired heaters rely on the flow of process fluids through the tubes to keep tube and firebox temperature down. If the temperature of the process fluid leaving the heater falls the control system calls for more fuel to be fed to the burners.
What is fired heat?
Fired Heaters, often referred to as furnaces (direct fired heaters), are pieces of equipment often used in processing facilities to heat gases or liquids up to a desired temperature.
What is the difference between direct fired and indirect fired gas heaters?
Indirect-fired heaters use about 80 percent of the combustion gases to heat air. The heaters are larger than direct-fired heaters, making them more difficult to transport. The heater uses oil or gas, as well as electricity.
What does indirect fired mean?
“Indirect Fired” means that the air is heated “indirectly”; the burner is fired into a heat exchanger. The air is heated when it passes over the heat exchanger and thus, the by-products of combustion remain inside the heat exchanger and do not come into direct contact with the process air.
What is direct fired heater?
Direct fired heaters are similar to a gas barbecue grill or your gas stovetop. With propane or natural gas heating, units force air directly through the flame to heat the air. Some units do not require electricity. Lower rental costs – Direct Fired Heaters are less expensive. Lower Maintenance Costs – Easier to …
What is the difference between direct and indirect fire?
Direct fire refers to firing of a ranged weapon whose projectile is launched directly at a target within the line-of-sight of the user. As such, indirect-fire weapons can shoot over obstacles or friendly units and the weapons can be concealed from counter-battery fire.
What are the types of indirect fire?
Indirect fires are divided into two basic categories: observed and unobserved.
What is an 11 Charlie?
Updated November 11, 2017. In the Army, military occupational specialty (MOS) 11C, Indirect Fire Infantryman, is a member of a mortar squad, section or platoon. The mortar is an infantry unit’s most powerful weapon. And despite its name, the job of infantryman has been open to female soldiers since 2016.
Can artillery direct fire?
Fire may be directed by an artillery observer or another observer, including manned and unmanned aircraft pilots, or called onto map coordinates.
What are the 3 types of artillery?
Artillery – Cannons
- Guns – heavy weapons with long barrels to batter fortifications with shot at long range.
- Howitzers – shorter barreled guns with “chambers” in the bores for smaller powder charges.
- Mortars – short chambered pieces used for lobbing shells at great elevation into the fortifications of the enemy.
How accurate is artillery?
Artillery accuracy is measured in “Circular Error Probable”- for example, if you have a CEP of 100 meters, you can expect 50% of the shells to land within 100 meters of the target.
How does artillery kill?
There are three ways that artillery most often claims its victims. The most common is through fragmentation of the shell, when the metal casing is split into many smaller bits and hurled at high speed in all directions. Most artillery rounds are designed to create some kind of shrapnel when they explode.
Which country has the most artillery?
Table of countries by artillery
Can artillery destroy a tank?
Field artillery Even a non-penetrating shell could still disable a tank through dynamic shock, internal armor shattering or simply overturning the tank. Field guns, such as the Ordnance QF 25 pounder, were provided with armor-piercing shot for direct engagement of enemy tanks.
What is the kill radius of a 155mm?
For a typical US 155 artillery round such as the M-107 normal cavity round, it has a kill radius of approximately 50 meters and a casualty radius of 100 meters.
How loud is a 155mm howitzer?
According to a US Army Public Health Command report, a 155mm Howitzer can produce 181 decibel blast. That is more than 25 times louder than an average rock concert, while a jet engine takeoff is normally about 150 decibels.
Can you legally own a howitzer?
In general, yes! While state laws vary, it’s generally legal to own a anything that does not use “fixed ammunition”. (Note: This is a bit complex, do your own research), including old style cannons without anything special. They are legally nothing more than toasters.