The pressure applied to the plastic during screw recovery. By increasing back pressure, mixing and plasticating are improved; however, screw recovery rates are reduced.

Increased pressure in the exhaust system that hampers the free flow of the exhaust gases.

A pressure developed when a moving liquid or gaseous mass passes through a restriction. "Backpressure" often refers to the pressure generated within the exhaust system from internal restrictions from tubing and tubing bends, mufflers, catalytic converters, tailpipes, or even turbochargers.

Resistance to flow in a system.

Pressure formed by the restriction of flow of either liquid or gas.

the measure of the pressure on the downstream side of a flowmeter.

The pressure on the low-pressure side of a refrigeration system (also known as suction pressure). Ball Bearings- bearings are grease lubricated. Most are sealed and do not need any lubrication service. Some, however, come with grease cups and can be lubricated with a grease gun. Motors that use ball bearings when new are supplied with enough grease in the bearings to lubricate them for a number of months. A small amount of grease should be added every tow-three months. Use a high grade grease on fully enclosed motors. Too much grease may cause the bearings to overheat.

The pressure resulting from restriction of full natural flow of oil or gas.

Pressure that resists the flow of fluid in a piping system.

A pressure that can cause water to backflow into the water supply when a user's waste water system is at a higher pressure than the public system.

The measurement of resistance to the forward flow of materials created by friction and viscosity of the material. Often discussed in relation to injection and extrusion molding.

Resistance to air flow; usually stated in inches H2O or PSI.

Back pressure is the plague of an inefficient exhaust system. When spent gases cannot flow freely through the pipes because of restrictions, they cause gaseous gridlock in your engine that goes all the way up to the cylinder. Since the gases cannot escape at the proper velocity, your engine has to work harder without yielding greater power. In effect, you lose horsepower, torque and fuel economy.

An induced resistance to flow through a system or the pressure within a system caused by fluid friction.

The resistivity of molten plastic material to forward flow.

Resistance to flow, normally expressed in pounds per square inch (psi).

Any condition that could create pressure in the discharge (outlet or downstream) side of the piping system that is greater than that in the supply (inlet or upstream) side of the system. Examples: pressure caused by gravity due to elevation differences; a pump installed in the system; or steam and/or air pressure.

Resistance to flow in the system.

The viscosity resistance of a material to continued flow when a mould is closing. In extrusion, the resistance to the forward flow of molten material.

The absolute pressure level as measured four pipe diameters downstream from the turbine flowmeter under operating conditions, expressed in pascals

Resistance of an exhaust system to the passage of exhaust gases. This can have an adverse effect on performance, fuel economy, and emissions. Excessive back pressure may be caused by a clogged catalytic converter, or a dented or crimped pipe.

1. In plumbing, a higher air pressure at the sewer side of the trap than on the fixture side of the trap; water can, under certain conditions, be forced out of the trap in the wrong direction towards the fixture. 2. In a refrigerating system, the pressure on the low side of the system, also called suction pressure or low-side pressure.

A phrase used to describe the pressure required to force fluid at a determined flow rate along a system's flow path, typically expressed in psi, bar, atm, or MPa.

Pressure against which a fluid is flowing. May be composed of friction in pipes, restrictions in pipes, valves, pressure in vessels to which fluid is flowing, hydrostatic head, or other resistance to fluid flow.

Pressure which creates resistance against a flow of water.

The resistance to the flow of exhaust gases through the exhaust system. By rerouting the exhaust gases for noise suppression, a muffler causes back pressure, but a straight pipe alone causes only minimal back pressure. Some engines require back pressure, so that removing the exhaust system will cause internal damage.

The pressure created by gravity at the base of a column of water. See Head Pressure.

Backpressure usually refers to the pressure exerted on a moving fluid by obstructions or tight bends in the confinement vessel along which it is moving, such as piping or air vents, against its direction of flow. For example, an automotive exhaust muffler with a particularly high number of twists, bends, turns and right angles could be described as having particularly high backpressure http://auto.howstuffworks.com/muffler5.htm. Back Pressure in the exhaust sense of the term, is usually termed as being a "bad thing" for performance, however in the ever increasing vigilance of the law, back pressure can be regulated to keep exhaust noise down using systems from simple butterfly valves to fully computer controlled units sensing pressure in the exhaust pipe itself.