List of Aircraft Fasteners Components - Page 4

Fasteners are a hardware component used to secure two materials. Nails, studs, screws, and bolts are the most frequently utilized fasteners across various markets; however, there is a wide variety of fastener types beyond the formerly mentioned. The fastener categorization describes hardware that is ideal in applications where a secure joint is required without creating a permanent affixment. As most fasteners are utilized in applications with high stress loads and high-risk for degradation, the hardware is generally designed to be non-permanent, and easily installed and replaced. Fasteners are selected primarily based on proof load, threaded or unthreaded, tensile strength, head type, length, materials, and standards specified by the applicable industry or governing bodies.

Materials
Fasteners are primarily categorized based on materials. Stainless steel, carbon steel, alloy steel, Inconel stainless steel, titanium, plastic polymers, and aluminum are all used in the manufacturing of fasteners. Platings or coatings are often applied to specified fasteners in order to reduce corrosion and increase wear-time. Alloys are the predominant material used for plating: cadmium, zinc, phosphate, chromium, silver, and/or nickel.

Standards and Traceability
While fasteners are used across many industries, from construction to commercial aircraft, there are many types of fasteners that vary in quality. Fasteners used in high-risk environments such as the aerospace, maritime, and automotive industries generally require higher standards and specifications due to the conditions the components operate in.

Uniform standards exist to regulate fasteners and ensure they meet particular specifications. Among a multitude of other standards, the American Society of Mechanical Engineers maintains several standards that clarify fastener types, dimensions, and materials. Military standards (MS) set by the US Military identify requirements for traceability and compliance for military and defense applications.

In addition, fasteners may also be set to standards specified  by the American National (Unified) Thread, Metric Thread, Coarse Series (UNC), Fine Series (UNF), Extra Fine Series (UNEF), and others.

At Methodical Purchasing, owned and operated by ASAP Semiconductor LLC, we supply high quality fasteners from manufacturers across the globe. Our product portfolio includes products from the following MFRs: Arconic, HI Shear, Huck International, PCC Fasteners, Monogram, Fairchild, Eaton, 3V Fasteners LISI Aerospace, Bell Helicopter, and more.

Types Of Fasteners
Aircraft Fastener types are sorted into the following categories: drive types, washer types, nut types, and anchoring products. Within these subsets, the fasteners are sorted by the formerly mentioned parameters. General fastener type families include: bolts, battens, buckles, buttons, cable ties, cams, clamps, clasps, clips, clutches, pins, flanges, frogs, grommets, hook-and-eye closures, latches, nails, pegs, nuts, retaining rings, rivets, screws, staples, studs, spacers, threaded fasteners, ties, washers, zippers, etc.

Drive Types
slotted, combination, socket, one way, Philips and Frearson, machine screws, square, and star.

Washer Types
 external tooth lock, internal tooth lock, square, flat, fender, finishing, split lock, dock, and ogee.

Nut Types
washer -faced nut, chamfered nut, jam nut, hex nut, heavy hex nut, nylon insert lock nut, nylon insert jam lock nut, wing nut, cap nut, flange nut, square nut, prevailing torque lock nut, k-lock or kep nut, coupling nut, slotted nut, castle nut, pin lock nut, and others.

Anchoring Products
concrete screws, spring toggle wings, stud anchors, sleeve anchors, lag shields, machine screw anchors, drop-in anchors, double expansion sleeves, plastic toggle, conical anchors, self-drilling drywall anchors, wood screw anchors, nail drive anchors, and anchor bolts, and hollow wall anchors

Aerospace Fasteners
Aircraft fasteners operate in high stress environments; extreme temperatures, extreme stress and loads, high pressures, and chemicals can accelerate degradation and corrosion. Accordingly, Aircraft fasteners are highly regulated and must be designed and manufactured according to high standards and specifications set by multiple organizations. Standards include but are not limited to those set by Boeing Aircraft Standards (BAC), Military Standards(MS), Aerospace Standards (AS), and National Aerospace Standards(NAS).

Aluminum has historically been the most prevalently used material in aerospace hardware. When utilized for spacecraft, the material requires extra treatment to edify its corrosion resistance properties. In this application, Aluminum must be cold heat formed. The material is most useful when aluminum alloys are used, as its tensile strength is higher.

Steels
Stainless steels and alloys are currently the most common forms of this material used in aerospace applications. CRES Series Steel Series 300 is the standard steel used for screws and bolts; this series is corrosion resistant but sensitive to high temperatures. Additionally, series 400 products are common in applications that involve high heat environments.

Superalloys
A286, Inconel 718, H-11, Waspaloy, Hastelloy, Monel, k-Monel, Haynes, MP35N, and MP 159 are all commonly integrated superalloys in the aerospace industry. Alloys used to construct fasteners are selected primarily based on proof loads and proof strength. This material is often used in aerospace applications because of its versatility, strength, and resistance to corrosion.

Automotive Fasteners
The Society of Automotive Engineers (SAE) is the governing specifications and standards provider for automotive fasteners; the hardware is ranked on their graded system. There are many different types of automotive fasteners, but the most commonly used fasteners in the automotive industry are bolts, nuts, and studs. These parts vary primarily by material minimum yield strength and minimum tensile strength.

SAE & Metric Standards
Fasteners of SAE 2, 5, and 8; and 5.8, 8.8, 10.9, and 12.9 metric grades are used in the automotive industry. They are all classified by proof loads, yield strength, and tensile strength. Automotive vehicles and builds often integrate Grade 5 (metric 8.8) fasteners and Grade 8(metric 10.9) fasteners.

• SAE Grade 5 (8.8): These fasteners are commonly used in bumpers, engine brackets, master cylinders, etc. This grade includes fasteners that are made of quenched and tempered medium carbon steel. It also encompasses hardware up to an inch in diameter and rated for 92,000 PSI yield strength and 120,000 PSI tensile strength. Hardware over one inch in diameter is rated for 81,000 PSI and 105,000 PSI tensile strength.

• SAE Grade 8 (10.9): Fasteners of this grade are used in critical fastening applications such as cylinder applications and suspension. SAE 8 is made of quenched and tempered medium carbon alloy steel. This grade of fastener is designed with a yield strength of 130,000 PSI and tensile strength of 150,000 PSI.

Automotive Bolts
Bolts are used in high tensile applications where strong, rigid attachment is needed. Compared to other fasteners, bolts have a longer grip length, with a shorter threaded portion for attachment of a nut. Bolts are divided into two main categorizations: American National Unified, or Metric. Further specifications vary based on threads per inch, nominal diameter, length, thread series, class fit, material grade, and head type; for metric bolts, they vary by metric, pitch, nominal diameter, material class, and head type. Common bolts used in the automotive industry are U-bolts, hub bolts, and wheel bolts.

Automotive Nuts
The most prevalent automotive nuts are standardly hex or square, with a threaded hole in their center. Nuts are used to secure and fasten bolts when attached to another material. Their grade must match or exceed the grade of the paired bolt.

Automotive Studs
Automotive studs are most commonly used in the build of an automotive engine, such as to secure a gasket head and cylinders, or in applications that need higher stress tolerance than a bolt can provide. Studs are threaded on both ends and have an unthreaded mid-section. They are secured to materials using nut screws. Automotive studs are constructed of various materials including bronze, aluminum, copper, brass, nylon, and plastic.

Marine Fasteners
Marine applications require fasteners that provide high anti-corrosion properties and anti-galvanize properties. Galvanic corrosion, crevice corrosion, and moisture degradation are all common issues encountered by hardware in a marine environment. Marine fasteners are therefore categorized primarily by their materials.

Stainless Steel
Stainless steel is the most common material used for fasteners. As a strong and rigid metal, this material is resistant to corrosion and offers optimal tensile strength for marine applications.

• CRES Series Steel 18-8, 304, and 316 are the most commonly used variety of stainless steel in the marine industry; Series 316 is prevalently used and offers the highest corrosion resistance.

• Hot Dipped Galvanized Fasteners: This material describes stainless steel that has been dipped in a thick layer of zinc, creating a tightly bonded alloy. This enables fasteners to have greater tensile strength, and greater corrosion resistant properties than standard stainless steel. Zinc plated steel is considered the most efficient material for engine hardware applications. Fasteners of this type are used in applications with higher loads, including that of shaft coupler bolts.

Silicon Bronze
Silicon bronze is made primarily of copper, silicon, and corrosion resistant alloys such as zinc. Silicon bronze operates well in the absence of oxygen and is highly resistant to corrosion from liquids and chemicals. This material is also less likely to galvanize other metals it is secured to. Silicon bronze fasteners are used in applications below the waterline, and in wooden vessel construction.