what is recoil pressure

Recoil pressure is the difference in pressure between two sides of an elastic structure. To get any hollow elastic structure to move from its resting volume, one side of the structure must be exposed to a higher pressure than the other. In respiratory physiology, recoil pressure is used with respect to the lung and the chest wall.

Full Answer

What is lung recoil pressure?

Lung elastic recoil pressure, or transpulmonary pressure (Pl), is the difference between the pressure inside the lungs (the alveolar pressure) and the pressure outside the lungs (the pleural pressure [Ppl): Pl = Palv − Ppl.

What is recoil pressure in welding?

The recoil pressure induced by the evaporation process occurring at the surface of a melt pool created by a laser beam impinging a metallic surface is the main mechanism of keyhole generation.

What is recoil in alveoli?

Lung recoil is the term used to describe the tendency of alveoli to rebound after being inflated. The primary determinant of lung recoil is surface tension, which is a force imposed by water molecules at the surface of liquids.

What is elastic recoil in the heart?

The pressure exerted on the arterial wall is returned to the blood when the artery returns to its normal size (elastic recoil)

What is LBM welding?

In laser welding (LBM) the joint is made either as a sequence of overlapped spot welds or as a continuous weld. Laser welding is used in the electronics, communications and aerospace industries, for the manufacture of medical and scientific equipment, joining small components.

Which laser is used in welding?

Types of lasers for laser weldingOscillation formSolid-stateYAG laserCW PulseYVO4PulseFiberYb fiberCW Q-switch Ultra-short pulseSemiconductorLD (laser diode) laserCW Pulse2 more rows

What do you mean by recoil?

Verb. recoil, shrink, flinch, wince, blench, quail mean to draw back in fear or distaste. recoil implies a start or movement away through shock, fear, or disgust. recoiled at the suggestion of stealing shrink suggests an instinctive recoil through sensitiveness, scrupulousness, or cowardice.

What causes lung recoil?

This phenomenon occurs because of the elastin in the elastic fibers in the connective tissue of the lungs, and because of the surface tension of the film of fluid that lines the alveoli. As water molecules pull together, they also pull on the alveolar walls causing the alveoli to recoil and become smaller.

Why do alveoli need to recoil?

Alveoli of the Lungs It takes some effort to breathe in because these tiny balloons must be inflated, but the elastic recoil of the tiny balloons assists us in the process of exhalation. If the elastic recoil of the alveoli is compromised, as in the case of emphysema, then it is difficult to exhale forcibly.

What does recoil mean in biology?

to pull back quickly1. to pull back quickly, such as towards a resting position upon removal of a strong opposing force. 2. (re´koil) a pulling back quickly. elastic recoil the ability of a stretched elastic object or organ, such as the lung or bladder, to return to its resting position.

How does elastic recoil function in breathing?

Lungs act as a spring-loaded bellows where muscle contractions expand the lung tissue and draw in air, while elastic recoil deflates the lungs when the muscles relax. The motion of the ribs and diaphragm transmits mechanical tension to the lungs across the pleurum, a layer of connective tissue.

What happens when the lungs recoil?

During quiet expiration, the cycle is reversed, the inspiratory muscles relax and the inward elastic recoil of the lungs results in deflation of the lungs. During deflation, the lungs and chest wall move as one unit. Airflow out of the lungs ceases when alveolar pressure equals atmospheric pressure (0 cm H2O).

What are the pressures for gas welding?

The fuel-gas pressure is 0.07 bar (1 psi - pound per square inch) or less. The oxygen pressure ranges between 0.7 to 2.8 bar (10 to 40 psi), depending on the size of the torch tip.

What is the safe working pressure of oxygen for cutting?

They shall have a minimum bursting pressure of 1,000 psig (6.8 MPa) and shall be protected by a safety relief device which will relieve at a maximum pressure of 500 psig (3.4 MPa).

What should acetylene pressure be?

Pressure control for oxyacetylene welding The adjustment of the pressure of the oxygen bottle must be set between 0.8 and 1.5 bar. The one for the acetylene bottle needs to be between 0.3 and 0.5 bar.

What pressure should oxygen and acetylene be set at?

Safe numbers are 40 psi for oxygen and 10 psi for acetylene, regardless of tip size. Simply adjust them until you get a neutral flame.

What is the difference between pleural pressure and pressure at the body surface?

All refer to the difference between the pleural pressure and the pressure at the body surface, which is atmospheric, and therefore zero. The recoil of the respiratory system, or PRS, is simply the recoil pressure of the lung plus the recoil pressure of the chest wall, which is Palv-Pbs. See Also:

What is recoil pressure?

Recoil pressure is the difference in pressure between two sides of an elastic structure. To get any hollow elastic structure to move from its resting volume, one side of the structure must be exposed to a higher pressure than the other.

Is palv or ppl positive?

While Palv and Ppl can be positive or negative, the recoil pressure of the lung is always be positive; that is, the alveolar pressure must always be greater than the pleural pressure. The greater the difference, the greater the recoil pressure, and the bigger the lung will be.

How should owners of vintage shotguns who are concerned about safeguarding their guns and protecting themselves proceed?

Given the above, how should owners of vintage shotguns who are concerned about safeguarding their guns and protecting themselves proceed? First, to combat recoil, always shoot light loads at velocities less than or equal to 1,200 fps. Second, to safeguard the barrels of vintage-type guns, adhere to one of the following tests of a gun’s integrity.

Why does a shotgun recoil?

Recoil is not a function of pressure but of the force caused by the acceleration of a load’s ejecta reacting backward through the weight and design of the shotgun to reach the shooter. Shooting heavy, fast loads in light guns exacerbates this problem. Shooting heavier shotguns with light, lower-velocity loads greatly reduces recoil and thus the stress on both the firearm and shooter.

What is the wear and tear agent on a shotgun?

The principal wearing and tearing agent on shotguns, especially light double guns designed for light loads, is not pressure; it’s recoil. Recoil is what stresses and breaks the metal parts of the action and trigger assembly, cracks the wood, loosens the fit of the barrels and whacks shooters in the face or shoulder.

Is it safe to shoot a shotgun without a nitro proof?

Always keep in mind that, to date, shooting so-called low-pressure (less than 7,000 psi) smokeless loads in a vintage shotgun without getting it CIP nitro proofed (or re-proofed) or SAAMI proofed beforehand is not a foolproof, safe practice. Failure to proof-test places the gun and shooter at risk. The record shows that sans nitro/smokeless proofing or re-proofing using current proof levels and procedures, vintage guns and/or their shooters do occasionally suffer the consequences.

Can you shoot smokeless loads in the UK?

Alternative 1: With a view to shooting modern smokeless loads, take the time and expense to have a vintage shotgun nitro proofed or re-proofed in the UK or Europe in accordance with CIP standards and procedures. Assuming the gun passes proof, be certain to know exactly at what pressure level it was proofed and exactly what the MAP is now for any smokeless-powder service loads approved by the proof house for use in it. Never shoot loads that exceed that MAP.

Can you shoot smokeless powder in a vintage shotgun?

One erroneous belief is that by merely shooting smokeless-powder loads that develop cha mber pressures no more than 7,000 psi, such loads can be safely shot in all vintage shotguns —Damascus-barreled or otherwise —made when only blackpowder loads existed and/or when smokeless powder was first coming on.

Is pressure a ballistic or internal concern?

Pressure, on the other hand, ultimately is an internal ballistic concern regarding primarily the strength of the barrel (s). This varies with the gauge, the strength of the metals used and the wall thickness of the barrel (s). It also goes to any metal fatigue or deterioration present inside the barrel (s) of an old firearm. But pressure is not any part of any equation used to calculate and express recoil.

How does recoiling affect the body?

Perception of recoil is related to the deceleration the body provides against a recoiling gun, deceleration being a force that slows the velocity of the recoiling mass. Force applied over a distance is energy. The force that the body feels, therefore, is dissipating the kinetic energy of the recoiling gun mass. A heavier gun, that is a gun with more mass, will manifest lower recoil kinetic energy, and, generally, result in a lessened perception of recoil. Therefore, although determining the recoiling energy that must be dissipated through a counter-recoiling force is arrived at by conservation of momentum, kinetic energy of recoil is what is actually being restrained and dissipated. The ballistics analyst discovers this recoil kinetic energy through analysis of projectile momentum.

What is counter recoil force?

The counter-recoil force is generally applied over a longer time period and adds forward momentum to the gun equal to the backward momentum supplied by the recoil force, in order to bring the gun to a halt.

How does recoiling work?

In heavier mounted guns, such as heavy machine guns or artillery pieces, recoil momentum is transferred to the Earth's surface through the platform on which the weapon is mounted. In order to bring the rearward moving gun to a halt, the momentum acquired by the gun is dissipated by a forward-acting counter-recoil force applied to the gun over a period of time after the projectile exits the muzzle. To apply this counter-recoiling force, modern mounted guns may employ recoil buffering comprising springs and hydraulic recoil mechanisms, similar to shock-absorbing suspension on automobiles. Early cannons used systems of ropes along with rolling or sliding friction to provide forces to slow the recoiling cannon to a stop. Recoil buffering allows the maximum counter-recoil force to be lowered so that strength limitations of the gun mount are not exceeded. Gun chamber pressures and projectile acceleration forces are tremendous, on the order of tens of thousands of pounds per square inch and tens of thousands of times the acceleration of gravity ( g's ), both necessary to launch the projectile at useful velocity during the very short travel distance of the barrel. However, the same pressures acting on the base of the projectile are acting on the rear face of the gun chamber, accelerating the gun rearward during firing. Practical weight gun mounts are typically not strong enough to withstand the maximum forces accelerating the projectile during the short time the projectile is in the barrel, typically only a few milliseconds. To mitigate these large recoil forces, recoil buffering mechanisms spread out the counter-recoiling force over a longer time, typically ten to a hundred times longer than the duration of the forces accelerating the projectile. This results in the required counter-recoiling force being proportionally lower, and easily absorbed by the gun mount. Modern cannons also employ muzzle brakes very effectively to redirect some of the propellant gasses rearward after projectile exit. This provides a counter-recoiling force to the barrel, allowing the buffering system and gun mount to be more efficiently designed at even lower weight.

What is Newton's law of momentum?

According to Newton's second law, the law of momentum -- changing the velocity of the mass changes its momentum , (mass multiplied by velocity). It is important to understand at this point that velocity is not simply speed. Velocity is the speed of a mass in a particular direction. In a very technical sense, speed is a scalar (mathematics), a magnitude, and velocity is a vector (physics), magnitude and direction. Newton's third law, known as conservation of momentum, recognizes that changes in the motion of a mass, brought about by the application of forces and accelerations, does not occur in isolation; that is, other bodies of mass are found to be involved in directing those forces and accelerations. Furthermore, if all the masses and velocities involved are accounted for, the vector sum, magnitude and direction, of the momentum of all the bodies involved does not change; hence, momentum of the system is conserved. This conservation of momentum is why gun recoil occurs in the opposite direction of bullet projection -- the mass times velocity of the projectile in the positive direction equals the mass times velocity of the gun in the negative direction. In summation, the total momentum of the system equals zero, surprisingly just as it did before the trigger was pulled. From a practical engineering perspective, therefore, through the mathematical application of conservation of momentum, it is possible to calculate a first approximation of a gun's recoil momentum and kinetic energy, and properly design recoil buffering systems to safely dissipate that momentum and energy, simply based on estimates of the projectile speed (and mass) coming out the barrel. To confirm analytical calculations and estimates, once a prototype gun is manufactured, the projectile and gun recoil energy and momentum can be directly measured using a ballistic pendulum and ballistic chronograph .

How is recoil determined?

The nature of the recoil process is determined by the force of the expanding gases in the barrel upon the gun (recoil force), which is equal and opposite to the force upon the ejecta. It is also determined by the counter-recoil force applied to the gun (e.g. an operator's hand or shoulder, or a mount).

How does a muzzle reduce recoil?

Muzzle devices can reduce the recoil impulse by altering the pattern of gas expansion. For instance, muzzle brakes primarily works by diverting some of the gas ejecta towards the sides, increasing the lateral blast intensity (hence louder to the sides) but reducing the thrust from the forward-projection (thus less recoil). Similarly, recoil compensators divert the gas ejecta mostly upwards to counteract the muzzle rise. However, suppressors work on a different principle, not by vectoring the gas expansion laterally but instead by modulating the forward speed of the gas expansion. By using internal baffles, the gas is made to travel through a convoluted path before eventually released outside at the front of the suppressor, thus dissipating its energy over a larger area and a longer time. This reduces both the intensity of the blast (thus lower loudness) and the recoil generated (as for the same impulse, force is inversely proportional to time).

What is recoil in naval?

Recoil (often called knockback, kickback or simply kick) is the rearward thrust generated when a gun is being discharged. In technical terms, the recoil is a result of conservation of momentum, ...

How Much Recoil Is Too Much Recoil?

Just seeing a list of recoil numbers is helpful, but it can still be difficult to know what that feels like in reality. Hopefully, the following comparison of some of the most popular cartridges today will be helpful.

How much recoil does a 50BMG have?

The same is true with guns. Some people look at the recoil energy of a 50BMG and think they will be KILLED by 83.17 ft-lbs of free recoil energy; however, the 50BMG is a physically heavy gun (usually over 30 lbs), so the recoil moves slowly (also because of the muzzle brake). People who have actually shot a .50BMG usually report mild recoil similar to a .308 Winchester. The recoil VELOCITY number of the .50 BMG is similar to a .308. Just recognize that it’s going to push you a lot–even though it won’t be painful.

How to calculate recoil energy?

The formula for determining the free recoil energy of a firearm is (Rifle Weight in Pounds/64.34) * (Recoil Velocity in FPS^2). This formula relies on the formula for recoil velocity, which is simply (Bullet Weight In Grains * Muzzle Velocity in FPS + Powder Charge in Grains * Muzzle Velocity * 1.75)/ (7000 * Rifle Weight in Pounds).

How much recoil does a 7mm Remington have?

The 7mm Remington Mag generates significant recoil of 22.15 ft-lbs at 13.32 fps. Smaller-framed or young shooters generally consider the cartridge as having high recoil, but its recoil is manageable for experienced large-framed shooters to be able to shoot it regularly.

What is the importance of selecting a rifle and cartridge combination which does not produce too much recoil for the shoot?

Selecting a rifle and cartridge combination which does not produce too much recoil for the shooters is critical to being able to shoot accurately without developing a flinch.

How much recoil does a Winchester 243 have?

The.243 Winchester’s recoil produces 9.22 ft-lbs of energy at a recoil velocity of 8.48 fps. That amount of recoil is low enough that even youth shooters have no problem shooting the cartridge. It feels more like a sudden vibration than actual kick.

What is the recoil of a Remington 7mm?

The 7mm-08 Remington’s recoil produces 14.88 ft-lbs of energy at a velocity of 10.68 fps. Because of its mild recoil, it is often recommended as a good hunting cartridge for youth and small-framed shooters.

Overview

Recoil: momentum, energy and impulse

Perception of recoil

Mounted guns

See also

External links