Online Store
N

 

N.P.S.H.A: The net positive suction head available to prevent cavitation of the pump. It is defined as atmospheric pressure gage pressure static pressure -vapor pressure - friction loss in the suction piping.



N.P.S.H.R.-1-: Net positive suction head required to stop a pump from cavitating. The pump manufacturer gives this number to you. Since testing with cold fresh water generated the number, it can be lowered in some cases if you are pumping hot water or some hydrocarbons.



Nanofiltration: A membrane treatment process, which falls between reverse osmosis and ultrafiltration on the filtration/separation spectrum. The nanofiltration process can pass more water at lower pressure operations than reverse osmosis, can remove particles in the 300 to 1,000 molecular weight range such as humic acid and organic color bodies present in water, and can reject selected (typically polyvalent) salts. Nanofiltration may be used for selective removal of hardness ions in a process known as membrane softening.



Nascent Oxygen: A single oxygen atom, not yet bonded to anything. Extremely powerful oxidizer when harnessed.



Natural Rubber: Natural rubber is a mixture of organic compound polyisoprene and small amounts of other organic compounds as well as water. This material is classified as an elastomer (an elastic polymer). It is derived from latex, a milky colloid produced by some plants. The plants are ‘tapped’, that is, an incision made into the bark of the tree and the sticky, milk colored latex sap collected and refined into a usable rubber. Natural rubber is used extensively in many applications. It is normally very stretchy and flexible and extremely waterproof.



NBR: Nitrile butadiene rubber (NBR) is a synthetic rubber also known as Buna N or Nitrile. It is presently the seal industry's most widely used and economical elastomer, NBR  combines excellent resistance to petroleum-based oils and fuels, silicone greases, hydraulic fluids, water and alcohols, with a good balance of such desirable working properties as low compression set, high tensile strength, and high abrasion resistance.



NCAA: National Collegiate Athletic Association, The governing body for intercollegiate competition and the recording agent for college swimming records.



NEC: National Electric Code. A document listing various codes and regulations that counties and townships work off of to set their standards. Also used by NEMA.



Negative pressure: Less than atmospheric pressure.



Negative pressure-1-: Pressure that is less than the pressure in the external environment.



Negative Terminal (Electrode): The terminal of a battery from which electrons flow in the external circuit when the cell discharges.



NEMA: National Electric Manufacturers Association. Sets standards that must be adhere to by a manufacture if they want this rating. Some of the standards are bolt hole pattern, shaft length, bell housing size, etc.



NEMA: National Electrical Manufacturers Association - an organization that develops voluntary standards of performance.



NEMA Type 1: Enclosures constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts and to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt).



NEMA Type 2: Enclosures constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).



NEMA Type 3: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 3R: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 3RX: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that will be undamaged by the external formation of ice on the enclosure that provides an additional level of protection against corrosion; and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 3S: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and for which the external mechanism(s) remain operable when ice laden.



NEMA Type 3SX: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that provides an additional level of protection against corrosion; and for which the external mechanism(s) remain operable when ice laden.



NEMA Type 3X: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that provides an additional level of protection against corrosion and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 4: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow, splashing water, and hose directed water); and that will be undamaged by the external formation of ice on the enclosure.



NEMA  Type 4X: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow, splashing water, and hose directed water); that provides an additional level of protection against corrosion; and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 5: Enclosures constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and settling airborne dust, lint, fibers, and flyings); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).



NEMA  Type 6: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (hose directed water and the entry of water during occasional temporary submersion at a limited depth); and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 6P: Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (hose directed water and the entry of water during prolonged submersion at a limited depth); that provides an additional level of protection against corrosion and that will be undamaged by the external formation of ice on the enclosure.



NEMA Type 12: Enclosures constructed (without knockouts) for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and circulating dust, lint, fibers, and flyings); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).



NEMA Type 12K: Enclosures constructed (with knockouts) for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and circulating dust, lint, fibers, and flyings); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).



NEMA Type 13: Enclosures constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and circulating dust, lint, fibers, and flyings); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing); and to provide a degree of protection against the spraying, splashing, and seepage of oil and non-corrosive coolants.



NEOPRENE (CR): Neoprenes were one of the first synthetic rubbers developed. Neoprene is an all-purpose polymer with many desirable characteristics and features high resiliency with low compression set, flame resistance, and is animal and vegetable oil resistant. Neoprene is principally recommended for food and beverage service. Generally, neoprene is not affected by moderate chemicals, fats, greases, and many oils and solvents. Neoprene is attacked by strong oxidizing acids, most chlorinated solvents, esters, ketones, aromatic hydrocarbons, and hydraulic fluids. Neoprene has a moderate temperature range of -20°F to 160°F.



NEOPRENE (CR): Neoprenes were one of the first synthetic rubbers developed. Neoprene is an all-purpose polymer with many desirable characteristics and features high resiliency with low compression set, flame resistance, and is animal and vegetable oil resistant. Neoprene is principally recommended for food and beverage service. Generally, neoprene is not affected by moderate chemicals, fats, greases, and many oils and solvents. Neoprene is attacked by strong oxidizing acids, most chlorinated solvents, esters, ketones, aromatic hydrocarbons, and hydraulic fluids. Neoprene has a moderate temperature range of -20°F to 160°F.



Nephelometric turbidity unit (NTU): unit of measure for the turbidity of water. Essentially, a measure of the cloudiness of water as measured by a nephelometer. Turbidity is based on the amount of light that is reflected off particles in the water.



Net Positive Suction Head (N.P.S.H.): the head in feet of water absolute as measured or calculated at the pump suction flange, less the vapor pressure (converted to feet of water absolute) of the fluid.



Net Positive Suction Head (N.P.S.H)-1-: Positive flow of water to the suction port of the pump.



Net Positive Suction Head Available (N.P.S.H.A.): Net positive suction head available. The head or specific energy at the pump suction flange less the vapor pressure head of the fluid.



Net Positive Suction Head Available: NPSHA, the amount of head available to the pump to overcome the NPSHR. NPSHA should be a larger number than NPSHR. NPSHA is affected by atmospheric pressure changes, altitude, pipe and fitting sizes, and elevation to the liquid being pumped.



Net Positive Suction Head Required (N.P.S.H.R.): Net positive suction head required. The manufacturers estimate on the NPSH required for the pump at a specific flow, total head, speed and impeller diameter. This is determined my measurement.



Net Positive Suction Head Required: NPSHR, the amount of head required by the pump to keep the liquid being pumped in a liquid state. The only way NPSHR can be changed is by changing the pumps' rotational speed or its impeller diameter.



Net Positive Suction Head: NPSH, static pressure on the suction side of a pump, must be high enough to prevent the water entering the impeller from boiling. There are two types of NPSH-NPSHR and NPSHA.



Neutralization: The addition of either an acid to a base or a base to an acid to produce a more nearly neutral solution. The use of alkaline or basic materials to neutralize acidity of some water is common practice in water processing to prevent corrosion of metallic home plumbing.



Neutrons: A component of an atom. Neutrons have no charge at all.



Newton: A metric unit of force. Kilogram x gravity.



Newtonian fluid: A fluid that does not change viscosity as it is agitated.



Newtonian fluid-1-:  A fluid whose viscosity is constant and independent of the rate of shear (strain). For Newtonian fluids, there is a linear relationship between the rate of shear and the tangential stress between layers.



Newtonian: a fluid whose viscosity does not change with the amount of strain it is subjected to.



NGVD of 1929: National Geodetic Vertical Datum of 1929. A geodetic datum derived from a general adjustment of the first order level nets of the United States and Canada. It was formerly called "Sea Level Datum of 1929" or "mean sea level" in the USGS series of reports. Although the datum was derived from the average sea level over a period of many years at 26 tide stations along the Atlantic, Gulf of Mexico, and Pacific Coasts, it does not necessarily represent local mean sea level at any particular place.



NGVD: National Geodetic Vertical Datum. (1) As corrected in 1929, a vertical control measure used as a reference for establishing varying elevations. (2) Elevation datum plane previously used by the Federal Emergency Management Agency (FEMA) for the determination of flood elevations. FEMA current uses the North American Vertical Datum Plane.



NiCad Battery: The most common type of secondary cell/battery, which uses nickel hydroxide as the positive electrode, cadmium/cadmium hydroxide as the negative electrode and potassium hydroxide as the electrolyte.



Nickel - Plated Ductile Iron:  Nickel coatings have received wide acceptance for use in chemical processing. These coatings have very high tensile strength, 50 to 225 ksi. To some extent, the hardness of a material is indicative of its resistance to abrasion and wear characteristics. Nickel plating is widely specified as a disc coating for butterfly valves.



NICKEL-PLATED DUCTILE IRON: Nickel coatings have received wide acceptance for use in chemical processing. To some extent, the hardness of a material is indicative of its resistance to abrasion and wear characteristics. Nickel plating is widely specified as a disc coating for butterfly valves.



Nitrate: An anion comprised of one nitrogen atom and three oxygen atoms. Nitrates are considered toxic in hemodialysis water and are also harmful to infants when consumed orally. Plant nutrient and fertilizer that enters water supply sources from fertilizers, animal feed lots, manures, sewage, septic systems, industrial wastewaters, sanitary landfills, and garbage dumps are nitrates.



NITRILE (NBR) — (BUNA-N): Is a general purpose oil-resistant polymer known as nitrile rubber. Nitrile is a copolymer of butadiene and acrylonitrile and has a moderate temperature range of -20°F to 180°F. Nitrile has good solvent, oil, water, and hydraulic fluid resistance. It displays good compression set, abrasion resistance and tensile strength. Nitrile should not be used in highly polar solvents such as acetone and methyl ethyl ketone, nor should it be used in chlorinated hydrocarbons, ozone or nitro hydrocarbons.



NITRILE (NBR):  (BUNA-N) is a general purpose oil-resistant polymer known as nitrile rubber. Nitrile is a copolymer of butadiene and acrylonitrile and has a moderate temperature range of -20°F to 180°F. Nitrile has good solvent, oil, water, and hydraulic fluid resistance. It displays good compression set, abrasion resistance and tensile strength. Nitrile should not be used in highly polar solvents such as acetone and methyl ethyl ketone, nor should it be used in chlorinated hydrocarbons, ozone or nitro hydrocarbons.



Nitrile:  Nitrile is a synthetic rubber also known as Buna N or NBR. It is presently the seal industry's most widely used and economical elastomer, Nitrile  combines excellent resistance to petroleum-based oils and fuels, silicone greases, hydraulic fluids, water and alcohols, with a good balance of such desirable working properties as low compression set, high tensile strength, and high abrasion resistance.



Nitrogen: When combined with chlorine, nitrogen creates chloramines, which do not belong in our pool. Nitrogen can be found in many swimmer wastes (perspiration, suntan oil, hair tonics, etc.) or be introduced by other means.



Nominal Filter Rating: Filter rating indicating the approximate size particle, the majority of which will not pass through the filter. It is generally interpreted as meaning 85 percent of the particles of the size equal to the nominal filter rating will be retained by the filter.



Nominal Voltage: The average terminal voltage of a cell or battery during its discharge.



Non lubricant: The fluid that will not maintain a film thickness of at least one micron at its operating temperature and load. A concern with mechanical sealing..



Non-aqueous Batteries: Cells that do not contain water, such as those with molten salts or organic electrolytes.



Non-Chlorine Shock: A granular form of potassium permonosulfate, used to oxidize materials such as microorganisms, contaminants or chloramines.



Non-point source (NPS) pollution: Pollution discharged over a wide land area, not from one specific location. These are forms of diffuse pollution caused by sediment, nutrients, organic and toxic substances originating from land-use activities, which are carried to lakes and streams by surface runoff. Non-point source pollution is contamination that occurs when rainwater, snowmelt, or irrigation washes off plowed fields, city streets, or suburban backyards. As this runoff moves across the land surface, it picks up soil particles and pollutants, such as nutrients and pesticides.



Nonswimming Area: Any portion of a pool, spa or hot tub where water depth, offset ledges or similar irregularities would prevent normal swimming activities.



Non-Transient, Non-Community Water System: A water system which supplies water to 25 or more of the same people at least six months per year in places other than their residences. Some examples are schools, factories, office buildings, and hospitals which have their own water systems.



Nozzle: An ejector part/device that increases the velocity of the liquid flowing through it by creating a partial vacuum at it's throat. Atmospheric pressure causes the increase in velocity.



Nozzle-1-: The part of the sprinkler where the water sprays out.



NPS Discharge: Nonpoint Source pollution: nutrients,. sediments, toxic substances, and pathogens that degrade waterways. NPS occurs mainly through storm water runoff.



NPT: Refers to the "National Pipe Thread" standard measurement. Outlet/Discharge The opening through which the water exits the pump.



NPT-1-: Refers to the National Pipe Thread standard measurement.



NSF: National Science Foundation: a U.S. government-funded agency which provides fundamental research and education in all the non-medical fields of science and engineering.



NTU: Nephelometric Turbidity Unit: An instrumental means of measuring water clarity based upon the intensity of light scattered by suspended individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in air.



Nucleus: Can have as many as seven layers or orbits of electrons moving around it.