Glossary

The NE Series Nylon Insert Lock Nut — also referred to as a Nylok™ Nut, Stop Nut, Plastic Insert Lock Nut, Regular Series Nylon Lock Nut, Non-Metallic Insert Nut, Polyamide Lock Nut, or Nylon Insert Hex Nut — is a nut with many identities but designed with one purpose. The Nylon Insert Hex Nut is a top-lock style with an elastic nylon ring.

Near net forming is a manufacturing method where a fastener is forged or shaped very close to its final dimensions, reducing the amount of machining and finishing needed. Unlike traditional machining, which starts with a block of material and cuts away large amounts of excess, near net forming uses processes like cold heading, hot forging, or precision casting to produce a fastener that already resembles the finished product.

This approach improves efficiency, lowers material waste, and enhances strength since the forming process aligns the grain structure with the fastener’s shape. As a result, near net forming is widely used in producing bolts, screws, and aerospace-grade fasteners where performance, cost savings, and reliability are critical.

A Newton meter (N·m) is the SI (International System of Units) measurement for torque, which is the rotational equivalent of force. It represents how much rotational force (moment) is applied around an axis, such as when tightening a bolt or turning a wrench.

By definition, one Newton meter is the torque produced by a force of one Newton acting perpendicularly at a distance of one meter from the axis of rotation. In equation form, torque (τ) is expressed as:

τ = F × r

where:

- τ = torque (in Newton meters, N·m)

- F = force applied (in Newtons, N)

- r = perpendicular distance from the axis of rotation (in meters, m)

For example, if you apply a force of 10 Newtons at the end of a 0.5-meter-long wrench, the torque you generate is:

τ = 10 N × 0.5 m = 5N\cdotpm

This means you’re applying a twisting moment of 5 Newton meters about the bolt’s axis.

In everyday terms, torque describes how much twisting force you’re applying. A higher torque value means a stronger rotational effect—tightening a bolt more firmly, turning a motor shaft harder, or accelerating a wheel faster.

To visualize the relationship:

- A Newton (N) measures linear force (how hard you push or pull).

- A Newton meter (N·m) measures rotational force (how hard you twist).

Torque is also commonly expressed in pound-feet (lb·ft) or inch-pounds (in·lb) in imperial systems. The approximate conversions are:

- 1 N·m ≈ 0.738 lb·ft

- 1 lb·ft ≈ 1.356 N·m

In engineering, N·m is the standard unit for specifying tightening torque for bolts, nuts, and fasteners, ensuring the proper clamping force without over- or under-tightening.

Nickel is a hard, silvery-white metallic element with the chemical symbol Ni and atomic number 28. It is a transition metal known for its strength, ductility, and excellent resistance to corrosion and oxidation, even at high temperatures. Nickel plays a crucial role in modern metallurgy and manufacturing—particularly in the production of stainless steels, high-performance alloys, and protective coatings.

In its pure form, nickel is tough, malleable, and magnetic at room temperature. It has a high melting point of 1,455°C (2,651°F), making it suitable for demanding applications such as jet engines, turbines, and heat exchangers. The metal forms a protective oxide layer on its surface when exposed to air, which helps prevent further corrosion—a property that makes it especially valuable in harsh or marine environments.

Nickel is most commonly used as an alloying element. The majority of the world’s nickel production—over 65%—is used to make stainless steel, where it combines with chromium and iron to increase corrosion resistance, toughness, and strength. It’s also a key component in nickel-based superalloys, which maintain strength and stability under extreme heat and stress, making them essential for aerospace, energy, and chemical processing industries. Other common nickel alloys include Monel (nickel-copper), Inconel (nickel-chromium), and Nichrome (nickel-chromium resistance wire).

Nickel also serves as a protective coating in nickel plating—a process that deposits a thin layer of nickel onto steel or other metals to improve wear resistance, corrosion protection, and appearance. This technique is used in fasteners, tools, electrical components, and decorative hardware.

Beyond metallurgy, nickel has important electrical and chemical uses. It’s used in batteries—particularly nickel-cadmium (NiCd), nickel-metal hydride (NiMH), and increasingly in nickel-rich lithium-ion batteries for electric vehicles. It’s also used in catalysts, coins, magnets, and electronic components.

Nickel occurs naturally in minerals such as pentlandite (Fe,Ni)₉S₈, garnierite, and laterites, with major deposits found in Indonesia, the Philippines, Russia, Canada, and Australia. Extraction involves both smelting of sulfide ores and hydrometallurgical processes for laterite ores.

Niobium (chemical symbol Nb) is a lustrous, gray transition metal known for its high strength, ductility, and excellent resistance to corrosion and high temperatures. It has an atomic number of 41 and lies directly above tantalum (Ta) in Group 5 of the periodic table, which explains why the two elements share very similar physical and chemical properties. In fact, niobium and tantalum often occur together in nature and must be carefully separated during processing.

Niobium has a melting point of about 2,468°C (4,474°F), making it one of the refractory metals—metals that can withstand extremely high temperatures without deforming. It forms a thin, stable oxide layer (Nb₂O₅) on its surface that gives it excellent resistance to oxidation and corrosion, even in harsh environments. This property, combined with its low thermal expansion and high melting point, makes it ideal for demanding structural and electronic applications.

One of niobium’s most important uses is as an alloying element in steels and superalloys. When added to stainless steel or high-strength low-alloy (HSLA) steels in small amounts (usually less than 0.1%), niobium refines grain structure and improves strength, toughness, and weldability. These niobium-bearing steels are widely used in pipelines, automotive frames, bridges, and skyscrapers. In superalloys, niobium increases high-temperature strength and creep resistance, making it essential for jet engine components, gas turbines, and rocket nozzles.

Niobium is also a key material in advanced technologies. In electronics, it’s used to produce niobium capacitors, which function similarly to tantalum capacitors but are less expensive. In the field of superconductivity, niobium-based alloys (like Nb-Ti and Nb₃Sn) are used to make superconducting magnets for MRI machines, particle accelerators, and fusion reactors, because niobium remains superconductive at relatively high magnetic fields and low temperatures.

The metal is naturally found in minerals such as columbite (also known as niobite) and pyrochlore, which are its primary commercial sources. Much of the world’s niobium supply comes from Brazil, which dominates global production, followed by Canada and a few other countries.

Nitrile O-rings (also known as Buna-N O-rings) are elastomeric sealing rings made from nitrile rubber, a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. They are among the most common and cost-effective types of O-rings used for general-purpose sealing in industrial, automotive, and aerospace applications.

A NM Nylon Insert Lock Nut (often just called a nylon lock nut) is a type of self-locking nut that uses a nylon insert to prevent the nut from loosening due to vibration or torque.

The stated or designated length of a fastener, used for identification and ordering. It represents the approximate or reference length rather than an exact, precise measurement (which can vary slightly within manufacturing tolerances). For most fasteners, such as hex bolts, it's measured from the underside of the head to the tip. However, for countersunk or flat heads, it's measured from the top of the head to the tip.

Non-destructive testing (NDT) is a group of inspection techniques used to evaluate the properties of a material, component, or assembly without causing damage. Unlike destructive testing, which breaks or alters a sample, NDT allows the part to remain in service after examination.

NDT is used to detect flaws such as cracks, voids, corrosion, or weld defects, as well as to measure material thickness, hardness, or structural integrity. Common NDT methods include:

Ultrasonic Testing (UT): uses high-frequency sound waves to detect internal flaws.

Magnetic Particle Testing (MT): reveals surface and near-surface cracks in ferromagnetic materials.

Dye Penetrant Testing (PT): highlights surface cracks with visible or fluorescent dye.

Radiographic Testing (RT): uses X-rays or gamma rays to create images of internal structures.

Eddy Current Testing (ECT): uses electromagnetic induction to detect surface defects and measure conductivity.

An NTE Nylon Insert Lock Nut is a specific type of self-locking hex nut that uses a nylon insert to prevent loosening under vibration or stress. The term “NTE” refers to the nut type and thread engagement, and is commonly found in military, aerospace, and industrial specifications.

An NTM Nylon Insert Lock Nut (also known as a Nylon-insert nut, nyloc nut, or nylon lock nut) is a type of lock nut that features a nylon insert or collar at the top. This insert creates a frictional resistance when threaded onto a bolt or screw, helping to prevent the nut from loosening due to vibration or torque.

An NTU Nylon Insert Lock Nut is a specific type of self-locking hex nut that includes a nylon insert and follows a defined naming convention, typically used in aerospace, defense, and industrial specifications. An NTU Nylon Insert Lock Nut is a thin-pattern, self-locking hex nut with Unified National threads (UNC or UNF) and a nylon insert.

The NU nylon insert lock nut is a full-height, metal hex nut with a non-metallic nylon insert pressed into the top of the nut. It is commonly used in industrial, automotive, and aerospace applications where a secure, vibration-resistant joint is required.

A nut is a type of fastener used in conjunction with a bolt to securely hold materials together in heavy-duty applications such as construction, manufacturing, and machinery. Industrial nuts are designed to withstand high loads, vibrations, and extreme conditions.

Nylon is a synthetic polymer belonging to the family of polyamides, known for its strength, elasticity, chemical resistance, and versatility. It was first developed by chemists at DuPont in 1935, making it one of the earliest and most important synthetic fibers. Its invention revolutionized textiles, engineering plastics, and industrial materials.

Chemically, nylon is created through a condensation polymerization reaction between a diamine (such as hexamethylenediamine) and a dicarboxylic acid (such as adipic acid). The resulting long-chain molecules are held together by amide bonds (–CONH–), giving the material excellent mechanical strength and thermal stability.

In its fiber form, nylon is lightweight, strong, smooth, and abrasion-resistant. It can be drawn into very fine threads and woven into fabrics that mimic silk but are far more durable. These properties made nylon famous during World War II, when it replaced silk in parachutes, ropes, and military gear, and later in stockings, clothing, and upholstery.

In industrial and engineering applications, nylon is used in the form of molded plastics or extruded components. It serves as a key material for gears, bushings, bearings, washers, nuts, fasteners, and cable ties, due to its combination of low friction, self-lubrication, high tensile strength, and wear resistance. Nylon is also used in automotive parts, power tools, conveyor belts, and fastener coatings, where it provides both mechanical and chemical performance advantages.

Nylon absorbs some moisture from the air, which can slightly affect its strength and dimensions. It also melts at around 220–265°C (428–509°F) depending on the specific type (e.g., Nylon 6, Nylon 6/6, Nylon 12).

There are several types of nylon, each optimized for different uses:

- Nylon 6/6 (Polyhexamethylene adipamide): Common in mechanical parts, known for strength and stiffness.

- Nylon 6 (Polycaprolactam): Used in fibers and films, easier to process with excellent surface finish.

- Nylon 12: More flexible, resistant to moisture and chemicals, used in tubing and coatings.

A nylon insert is a ring of nylon material embedded into the threads of a fastener, typically a hex nut. As the mating fastener is threaded into place, the nylon insert deforms around the threads, locking the mating fastener in place. This deformation creates a locking action by pressing tightly against the mating fastener’s threads, thereby reducing loosening caused by vibration or movement.

Nylon Insert Hex Flange Nuts — otherwise known as Nylok™ Flange Nuts, Flange Stop Nuts, Plastic Insert Flange Lock Nuts, Non-Metallic Insert Flange Nuts, or Polyamide Flange Lock Nuts — are designed with a built-in washer and nylon insert. As the nut is tightened, the bearing load is spread out over a larger area compared to Nylon Insert Hex Nuts — preventing damage to the clamping material (such as truck frames). The nylon locks the nut in place as it grabs onto the thread. Earnest offers the nuts in inch carbon steel (Grade A or 2) and Grade G (8).

The DIN 982 Nylon Insert Lock Nut — also referred to as a Nylok™ Nut, Stop Nut, Plastic Insert Lock Nut, Regular Series Nylon Lock Nut, Non-Metallic Insert Nut, Polyamide Lock Nut, or Nylon Insert Hex Nut — is a nut with many identities but designed with one purpose. The Nylon Insert Hex Nut is a top-lock style with an elastic nylon ring. This ring grabs onto the thread as it’s fastened — preventing the nut from loosening in vibrating applications. Earnest offers DIN 982 Nylon Insert Lock Nuts in Property Classes 6 and 8.

A Nylon Insert Lock Nut with Nylon Cap is a type of lock nut that combines the secure fastening of a nylon insert lock nut with the protective and aesthetic benefits of a cap made of nylon. This nut is designed to provide a vibration-resistant fastening solution while also protecting the exposed bolt threads and enhancing the overall appearance.

A pre-applied nylon strip on a fastener’s threads that adds friction to prevent loosening from vibration. Also called a non-metallic prevailing torque patch, it’s made by heating nylon to a liquid state and applying it to one side of the threads. As the fastener is tightened, the nylon creates a wedging action between the threads, providing a reusable, non-permanent locking feature. Nylon patches can typically be reused up to five times and perform reliably up to 250°F.