From the boresight line flareouts electricity khan academy

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A flareback, in simple terms, is unspent propellant from electricity vampires the round that mixes with oxygen and creates a fireball from the breechblock after the round has been fired during case base ejection. A flareout is a secondary blast envelope at the muzzle end of the gun. While the gun is doing what it is supposed to do with a flareout, the situation is ideal for a flareout to become a flareback.

As the projectile travels down the gun tube, it passes the bore-evacuator holes. Propellant gases expand into the bore evacuator, storing pressure to aid in the evacuation of spent propellant gases. Pressure varies due to round type and atmospheric conditions. The first round can reach up to 200 pounds per square inch in the bore evacuator because of a secondary reaction with the air in the evacuator. Bore-evacuator holes are drilled at 30-degree angles toward the muzzle end of the gun tube to allow the flow of gases to exit.

Once shot exit occurs, rapidly expanding propellant gases create a blast envelope at the gun’s muzzle. Flareouts create a second blast envelope. This is an indication that not all gases are being spent at the proper time. While, in this case, the bore evacuator is working to expel all unspent gases, the fear is that a flareback may occur at anytime.

The bore evacuator asserts itself as gun-tube pressure drops and allows the gases to exit the muzzle end of the gun. Normally, that is the white puff of smoke you see at the end of firing. The gas vs diesel truck flareout is that white puff of smoke that has turned into a second blast gas city indiana envelope. The scavenging part of the system is the difference between low pressure from the breech opening to the bore-evacuator holes and high pressure from the bore-evacuator holes to the muzzle end of the gun, creating a partial vacuum.

Past unit-maintenance standard operating procedures would have us clean the bore evacuator and then slap a healthy coat of GAA, or “grease aircraft automotive,” on it. The thinking process behind this is it would prevent rust and be easier to clean after firing. This practice could potentially clog up the bore-evacuator holes, not allowing the bore evacuator to do its job. The proper way to maintain the bore evacuator is to use “cleaner lubricant and preservative” (CLP), National Stock Number (NSN) 9150-01-054-645. Using CLP provides rust protection while limiting the chance of the bore-evacuator holes becoming clogged.

“Tank gun tubes which have fired depleted uranium (DU) ammunition may have DU residue on the inside surfaces and the bore evacuator. This contamination may be both removable and fixed (remaining for the life of the tube). DU emits very low levels of radiation. Personnel cleaning the gun tube or bore evacuator must wear rubber/ latex gloves (even if the gloves have been worn, always wash hands after cleaning gun tube). Do not touch gloves to face or other parts electricity use in the us of body. Wash hands after removing gloves. Depress the gun tube as much as possible to prevent contaminated cleaning fluid from flowing into breech or crew compartment.

“Rags and cleaning fluid generated during maintenance on the bore evacuator or during the gun-tube cleaning process must be disposed of as low-level radioactive waste. Mop up all excess cleaning fluid with rags, and (double) bag all trash, including gloves, in two plastic bags. Ensure bag is tagged as containing radioactively contaminating material. Be sure the tag lists contents (gloves, rags, towels, etc.) and isotope (DU). Contact your local radiation-protection officer for disposal instructions.”

Once everything is disassembled (Figure 1), start with inspection of the bore evacuator itself. Check the bore evacuator for any type of damage (Figure 3). Check for any rub marks, dents, chips or cuts on any part of the 1940 gas station photos bore evacuator. Check around the angled seat ends (Figure 2) for any type of damage. Any damage to this area will not allow the seals to seat properly and will allow gases to leak out. The bore evacuator will not pressurize properly and may cause a loss of velocity of the shot or possible flareback. If gases are leaking, you may see black-powder marks around seal areas. This is a sign that seals or bore evacuator may be damaged.

After inspecting the bore evacuator, inspect the seals, which are called packing (Figure 4) in the TM. Check them for tears, cuts, gouges or deformation. Don’t stretch them out when removing and installing them la gastritis. Packing should be replaced semiannually in accordance with the TM 9-2350-264-1-3 mandatory-replacement-parts list, Page 0511-102, Table 2, Item 27. If new packing is required, notify field maintenance.

Next, move to the outside part of the gun tube, where the bore evacuator sits during normal operations (Figure 5). Inspect it for corrosion. If pitting exceeds .02 inches deep on unpainted, or .04 inches deep on painted surfaces, and covers 80 percent of the surface area, notify field maintenance. Check the bore-evacuator holes (Figure 6) to ensure they are not clogged. Pipe cleaners (NSN 9920-00-292-994) are the key to success. Use only CLP to clean and lubricate the surface and the hardware parts. You can use a light j gastroenterol coat of GAA (NSN 9150-00-145-026) on the packing.

Performing all maintenance and scheduling maintenance procedures in accordance with the proper TMs will keep the tank in operating condition. The checks are to find, correct or report problems. This will prevent shortcomings on the equipment you are assigned. Understanding the importance of maintaining your equipment will ensure the readiness of the equipment and the unit.