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All fasteners perform the same function—mechanically joining and securing two or more parts together. However, differences in type, quality, shape, and material significantly influence the fastener’s performance and service life. Understanding the functional varieties of the different types available, including nuts, bolts, and washers, is essential to selecting the appropriate fastener (and fastener supplier) for your project.
At National Bolt & Nut Corporation, we pride ourselves on offering a full range of stock and custom fasteners that provide durability and high performance at competitive prices. The following guide outlines a small selection of the types of fasteners available in our total inventory to help you choose the optimal product for your fastening application.
Types of Fasteners
National Bolt & Nut manufactures a variety of fasteners, including bolts, nuts, and washers.
Types of Bolts
Bolts are one of the most versatile structural fasteners, available in a vast array of configurations to suit different materials and strength requirements. These fasteners differ primarily in thread specification, length, and head shape, with varying combinations of these characteristics resulting in bolts with different functions. They typically require a drilled hole and a complementary nut, or tapped mating part for installation, and, unlike screws, they are generally not tapered. The terminology distinguishing between the types of bolts is often inconsistent and incorrectly used interchangeably for screws, so it’s best to select your bolts based on your project specifications rather than the exact name indicated on a supplier’s website.
Some of the types of bolts that we manufacture at National Bolt & Nut include:
- Carriage bolts: Carriage bolts feature a domed or countersunk head with a square underside that prevents turning post-installation. They are often used with wood and masonry.
- Flange bolts: Flange bolts are a specialized type of hex head bolt that has an integrated flange that serves as a washer component to more evenly distribute the load.
- Plow bolts: Similar to carriage bolts, some plow bolts have a square-shaped countersunk top. Others have a domed design. These bolts are ideal for heavy-duty applications like industrial machinery.
- Hex head bolts/ Hex Head Cap Screw: Characterized by their hexagonal head shape, hex head bolts are a broader category of bolts that requires installation with a wrench. They are available in many lengths and threading varieties. Hex Head Cap Screws have tighter tolerances and are the most common Hex Bolt category.
- Square head bolts: Like hex head bolts, square head bolts are defined by their head shape—i.e., square. This head design facilitates tooling gripping, allowing for easier installation.
- Socket Head Cap Screws/ Allen bolt: Socket head cap screws have a flat chamfered top surface with a smooth or knurled cylindrical sides. Forged heat-treated alloy examples are high strength fasteners intended for the most demanding mechanical applications, with special alloy formulations.
- Additional bolt types: The other bolt types that we can custom manufacture include anchor, belt (e.g., eye, hook, J, and U), countersunk, lag, and T-handle bolts.
Types of Nuts
- Coupling nuts: A coupling nut is a longer, cylindrical nut that joins two male threads. This component can be used to add length to an installation.
- Flange nuts: Similarly to flange bolts, flange nuts feature a round flange that acts as an external washer, and allowing for a more even load distribution.
- Hex nuts: Hex nuts are hexagonally shaped. These nuts are extremely versatile but require a wrench for installation. The types of hex nuts we supply include finished hex, semi-finished hex, hex flange, hex jam, heavy hex, and slotted hex.
- Lock nuts: Lock nuts are available in a range of shapes and are used to secure other nuts and prevent them from loosening. Types of Lock nuts include All Metal Lock nuts with Top or Side locking features, Serrated Hex Flange, and Nylon Inserts.
- Slotted nuts: Slotted nuts are designed and constructed such that they can form a locking mechanism with a cotter pin or a safety wire.
- Square nuts: Square nuts are characterized by their square shape. This head shape increases the surface area of the fastener and the amount of friction it experiences, reducing the risk of it loosening.
- Wheel nuts: Wheel nuts are a broad category of nuts that are used in automotive wheel applications.
- Additional nut types: The other nut types we can custom manufacture include cap, castle, conical, Keps, thumb, and wing.
Types of Washers
Washers are disk-shaped components that provide enhanced control over locking and friction when used with other fasteners. These fasteners may also feature teeth, indentations, and other unique structural mechanisms for use in more specialized applications. In general, they serve a variety of functions, including preventing loosening of the fastener assembly, protecting the surface under a fastener, and distributing the pressure more evenly during installation and use.
Compared to nuts and bolts, washers have much fewer variants available. However, among the washer types, there remain important distinctions. Like nuts, washers should be complementary to your selected bolt and chosen to suit your unique fastening application.
Our range of standard washers includes:
- Beveled washers: Beveled washers are formed with a slightly angled surface, allowing them to join materials that are not parallel to one another.
- Flat washers: Flat washers are the most common type of washer. They provide a larger surface area for better load distraibution. Different thicknesses are available for a variety of hold strengths.
- Lock washers: Lock washers come in many shapes, such as helices, toothed rings, conical, or spring, each designed to prevent slippage of fasteners in demanding applications. They are commonly used in environments that experience high levels of vibration.
- Structural washers: Structural washers are one of the most heavy-duty washer options available. These thick fasteners are designed to withstand the high load pressures of construction.
In addition to these three types of fasteners, National Bolt & Nut offers other fasteners—e.g., dowels, hose and shaft couplings, nails, pins, rivets, rods, screws, shackles, and studs— as both stock and custom fastening solutions.
Extra Information About Fasteners
NBN Suggests you consult with an engineer to best identify which fasteners to call out in a specific application. There are many factors to consider when selecting a fastener. Other important considerations include understanding how individual fasteners work together to form a joint, use cases, thread patterns, and material and finishing options, employing an engineer will save money and headache in the long run.
Uses of Fasteners
Fasteners find use in a variety of industrial applications, including:
- Agriculture. In the agricultural industry, fasteners are used in field irrigation and filtration systems, drying units, and other farming equipment, buildings, and grain bins.
- Automobile and transportation. Fasteners are used to assemble a wide range of vehicles, including cars, trucks, airplanes, and specialized construction equipment.
- Building and construction. Scaffolding and other support structures used in building and construction applications require copious amounts of fasteners to ensure stability during use.
- Chemical refining. In chemical refineries, fasteners are made using high performance, corrosion resistant materials, such as stainless steel, tool alloys, and exotic metals. They find application in equipment such as heat exchangers, tanks, and processing systems.
- Marine. Fasteners employed in the marine industry require excellent corrosion resistance to withstand the long periods of exposure to saltwater that marine decks, ramps, bulkheads, and tanks experience. Materials such as stainless steel and aluminum are commonly used for marine fasteners.
- Military. Military fasteners are designed to withstand extreme temperatures, corrosive compounds, and high stress environments. Common uses include heat exchangers, equipment motors and engines, and processing equipment.
- Oil and gas. Similar to military fasteners, fasteners used in the oil and gas industries must provide consistent performance in high stress and corrosive conditions. These fasteners find application in processing equipment such as drilling rigs, tanks, and pumps.
- Power generation. Fasteners for the power generation industry are made of high strength and corrosion resistant materials such as aluminum, copper, nickel alloys, stainless steel, and other steel allows. Typical applications include use in electrical equipment, exhaust systems, motors and pumps, and storage containers.
Right-Handed vs. Left-Handed Thread Patterns
Many fasteners, including nuts and bolts, feature threads to facilitate their fastening function. Threads are available in both right-handed and left-handed patterns. Although most applications use right-handed (i.e., clockwise running) threads, special circumstances require left-handed (i.e., counterclockwise running) threads to resist forces that would otherwise loosen the fastener.
Fasteners are available in a wide range of materials and finishes. Choosing the right material and material finish for your fastening application is as essential as selecting the proper type, size, and shape.
The most common fastener materials are aluminum, carbon steel, and other alloys. However, manufacturers also use alternative materials, such as brass and plastic, for fasteners intended for specialized applications. For instance, silicone bronze is appropriate for aquatic environments.
Finishing options are also available to improve aesthetic or functional properties, such as increasing material strength or corrosion resistance. Some of the types of finishing that we provide include black oxide, hot dip galvanizing, zinc plating, and chrome plating, to name a few of the many plating options that are available.National Bolt & Nut Corp.: Your Source for Quality Fasteners
At , our experience allows us to offer high quality products and services to meet the fastener needs of a diverse set of industrial clients. We serve industries ranging from construction and transportation to alternative energy and mining, in each case, meeting and exceeding customer requirements.
To learn more about our standard and custom fastener products and how they can benefit your next project, contact us, or request a quote today.
How do I know what size bolt washer I need? ›
Washers are not. It is important to note that when matching a washer with a screw or a bolt, the diameter of the shaft of the screw or bolt should be matched to the inner diameter of the washer. For example, a ¾-16 bolt should be matched with a ¾ washer.What are the different types nut and bolt? ›
Bolt types include eye bolts, wheel bolts and machine bolts, while types of nuts include cap nuts, expansion nuts and u-nuts.What are nuts bolts washers called? ›
Our whole life revolves around these simple tools we call fasteners. Be it fixing simple water taps at home or constructing buildings, nuts, bolts and washers are always needed to make our life easier. However, one should always look around for the best quality fasteners to ensure durability and permanence.How do you identify different bolts? ›
The number markings are engraved on the top or side of the bolt head. Common metric classes are 5.8, 8.8, 10.9, and 12.9. The higher the numbers are, the stronger the material of the fastener is.How do I identify my bolt manufacturer? ›
Line stamped under “B8M”. Manufacturer's identification mark, e.g., “X” ( on head of bolts and screws and on one end of studs and stud bolts). Manufacture's identification mark, e.g., “X”, applied to head (raised or depressed at option of manufacturer).Does every bolt need a washer? ›
Not all materials require the use of washers. But for wood and other relatively soft materials, washers are useful to protect against stress-related damage when the threaded fastener is driven into the material.What are the 4 types of washers? ›
- Flat washers. Also called a flat nut washer. ...
- Finishing washers. Also known as flush countersunk washers. ...
- Shoulder washers. Used as a bushing to insulate fasteners or shafts. ...
- Tooth lock washers – external. ...
- Retaining washers. ...
- Sealing washers. ...
- Spring washers – single wave. ...
- Cup washers.
The three main types of washers are plain washers, spring washers and lock washers.What are the three types of bolts? ›
The principal types of bolts commonly used include: Anchor Bolts. Blind Bolts. Carriage Bolts.What are the strongest nuts and bolts? ›
Grade 9 Bolts
Grade 9 structural bolts, also known as grade 9 hex cap screws, are one the strongest structural bolts that can be used today. While the typical grade 8 bolt has a tensile strength of 150,000 PSI, a grade 9 bolt has a tensile strength of 180,000PSI.
Should washer go under nut or bolt? ›
The lock washer should be placed under your threaded fastener - i.e., underneath a nut or the head of a screw or bolt. In assemblies where you have a nut and a bolt, the washer should be placed between the nut and the head of the bolt. You can then tighten the threaded fastener as normal.What is the best grade of nuts and bolts? ›
Grade 8 / Grade G
Thus they are stronger and are used in demanding applications such as automotive suspensions. Grade 8 bolts have 6 evenly spaced radial lines on the head. Grade G is roughly equivalent to Grade 8.
Three radial lines will indicate an SAE grade 5 fastener, while six radial lines will indicate an SAE grade 8 fastener. These are the most common grades, but there are others.What does P stand for on a bolt? ›
Amazon has quietly added a new feature to its iPhone app that hopes to make it easier for you to find a spare part.What do the letters on top of bolts mean? ›
The markings on the heads of bolts serve two different purposes: The markings can indicate who manufactured the bolt. This will vary from manufacturer to manufacturer, but is usually one, two or three characters. The markings can identify the standard to which the bolt was made.Can you use nuts without washers? ›
Washers are important. They ensure that a nut is installed properly and prevent softer materials from damage by distributing the pressure over a greater surface area. Are washers necessary? Washers are not always necessary but it is common practice to use them anyway.Is it OK to stack washers on a bolt? ›
It is not a good practice to stack washers in a fastener joint. Each stacked element acts like springs in series, consequently, fastener joint stiffness would be compromised.Do washers help bolts stay tight? ›
Washers are typically wider than the bolt head, with the additional surface area adding extra friction to the joint to maintain the clamp force. However, simple split washers, sometimes called helical spring washers, have been found to actually loosen the bolt under vibration even faster than a joint with no washer.What are the 9 types of nuts? ›
- Almonds. Almonds are incredibly popular due to their flavor, impressive nutrient profile, and relatively cheap cost. ...
- Pistachios. ...
- Walnuts. ...
- Cashews. ...
- Pecans. ...
- Macadamia nuts. ...
- Brazil nuts. ...
What are 5 types of nuts? ›
- Pistachios. ...
- Hazelnuts. ...
- Cashews. ...
- Walnuts. ...
- Marcona Almonds. ...
- Macadamia Nuts. ...
- Peanuts. ...
Type A is a series of steel washers with broad tolerances, where precision is NOT critical. Type B is a series of flat washers with tighter tolerances where outside diameters are categorized as Narrow, Regular or Wide for specific bolt sizes.What are washers without holes called? ›
Flat washers are used to increase the bearing surface of a nut or fastener's head thus spreading the clamping force over a larger area. They can be useful when working with soft materials and oversized or irregular shaped holes.What are the main washer types? ›
- Plain washers.
- Spring washers.
- Locking washers.
- Medium/regular load: When the drum is around half full, you have a medium or regular wash.
- Large load: If you want to do a large load, the washer should be three-qaurters full.
- Extra-large load: If you have an extra-large amount of laundry, you can go for an extra-large load size.
Front load washers are generally more efficient, since they're designed to use less water even if they have slightly longer cycle times. Top load washers use more water even if their cycles can be faster than that of a front load washer.What are the 5 basic types of fasteners? ›
- Fastening with Nails. Nails are one of the easiest methods of joining two or more pieces wood. ...
- Screws Provide Durability and Disassembly Options. ...
- Bolting Things in Place. ...
- Permanent Joins with Rivets. ...
- Adhesive Anchoring.
1, Group A is composed of those materials that have a tensile strength similar to ASTM A325, and includes ASTM A325/A325M, F1852, A354 Grade BC and A449. Group B is composed of those materials that have a tensile strength similar to ASTM A490, and is composed of ASTM A490/ A490M, F2280 and A354 Grade BD.What nut is the king of nuts? ›
When it comes to nuts, Walnut is considered to be the king of nuts.What is the toughest bolt? ›
BUMAX® Ultra – the world's strongest bolt
Since its launch in 2014, the BUMAX® Ultra range has proven that it is capable of exceeding tensile strengths of between 1 500 to 1 700 MPa on various applications, with good corrosion resistance and an operating range of between -50 and 400°C.
What happens if you don't use a washer with a bolt? ›
If you don't use a washer, the hexagonal shape of the nut and bolt can leave an indentation in the bearing surface. Washers for bolts prevent this from happening.Should washer be bigger than bolt? ›
- Washers must always be larger than exact diameter of screw. Determining the Diameter: Both nuts and washers are sized by the fasteners they fit.Do washers go on same side as nut? ›
These washers are made by removing part of a flat washer so that a twisted shape forms. However, spring washers are placed on the nut side of the fastener only, unlike flat washers, which are placed on the bolt and nut sides. Spring washers act like a spring and provide a preload between two surfaces.What does M10 mean on a bolt? ›
M10-1.0 x 20
Taking a closer look at this description, let's explore its meaning: M = This designates the fastener is a metric size. 10 = The nominal diameter in millimeters. 1.0 = The thread pitch, or distance between threads, in millimeters. 20 = The fastener's length, in millimeters.
Here's an example metric bolt specification: M8-1.0 x 20. This bolt specification breaks down like this: The letter 'M' indicates that this bolt uses a metric thread. The number '8' refers to the nominal diameter of the bolt shaft in millimeters.What does 2H mean on a nut? ›
The 2H hex nut bears a clear mark on the fastener face, indicating the grade (2H). The grade 2H designation signifies nut formation, including the method of heat treatment, quenching, and temperature range required for tempering.What is the difference between Grade A and Grade C nuts? ›
Grade A nuts are used with low carbon steel heavy hex bolts. Grade 5 are used with medium carbon cap screws and bolts. Grade C nuts are recommended to be used with A325 structural bolts. Grade 2H nuts are recommended for use in high pressure and high temperature service.Which is stronger Grade 8 or Grade 10 bolt? ›
The common class (grades) for metric are 5.8, 8.8, 10.9 and 12.9. Each grade has a specific bolt strength. No matter the system used, the higher number means the stronger the bolt. For most home and automotive applications, you won't need anything more than a grade 8 bolt strength or metric class 10.9.What does 4.8 mean on a bolt? ›
|Property Class||Size Range (mm)||Minimum Proof Strength (106 Pa)|
|4.6||M5 - M36||225|
|4.8||M1.6 - M16||310|
|5.8||M5 - M24||380|
|8.8||M1.6 - M36||600|
A2 stainless steel is often referred to as 304 or 18/8 Stainless. 18/8 actually refers to the amount of chromium and nickel in the alloy – 18% chromium and 8% nickel. A2 (304, 18/8) is an austenitic steel and is non-magnetic. The chromium provides a corrosion and oxidation resistance, however it can tarnish.
What does Grade 5 bolt mean? ›
Grade 5. Manufactured from medium carbon steel and hardened for greater strength and durability, a grade 5 bolt is distinguished by 3 radial lines and promises tensile strengths between 105,000 and 120,000 psi. They are most commonly found in automotive applications or those that require medium strength.What does B mean on a bolt? ›
Grade B bolts and studs have a tensile strength between 60 ksi and 100 ksi. Their intended use is in flanged joints in piping systems with cast iron flanges.What does TB mean on a bolt? ›
After (S) comes (TB) and (TF) – both of these represent “fully tensioned” bolts.What does 8.8 mean on the head of a bolt? ›
So, in English, a Property Class 8.8 bolt is a bolt with a nominal tensile strength of 800 MPa and a nominal yield strength that is 80% of that nominal tensile strength, so 640 MPa.How do I look up a bolt? ›
You can browse through the app for the perfect restaurant to feed your cravings by using the in-app search feature. Simply click the magnifying glass icon then type the restaurant's name. Tap on the name in the search results to view the menu.Is there a free app to identify objects? ›
Cam Find is a free image recognition app that can identify objects and landmarks. The app uses image recognition software to identify objects in photos and then provides information about the object.What is the difference between Grade 2 and Grade 5 nuts? ›
A head with no markings is Grade 2, one with 3 lines spaced 120 degrees is Grade 5, and 6 lines spaced at 60 degree intervals is Grade 8. Nuts are marked in several different ways—see Identification Marks for Hex and Heavy Hex Nuts below.What does SC mean on a nut? ›
Nord-Lock has developed a range of washers specially designed for use in steel construction applications and to fit HV sets (bolts and nuts in accordance to the European standard EN 14399-4 / EN 14399-8), as the standard washers can't be used (see picture). These washers are named “SC” (Steel Construction washers).Do all bolts need washers? ›
Not all materials require the use of washers. But for wood and other relatively soft materials, washers are useful to protect against stress-related damage when the threaded fastener is driven into the material.Do you have to use salt when soaking nuts? ›
The salt helps activate enzymes that deactivate the enzyme inhibitors present in nuts. When soaking grains or beans, a more acidic substance is often used, but since nuts and seeds contain less phytic acid than grains/legumes but more enzyme inhibitors, the salt is more beneficial.
Do you need a washer on both sides of a bolt? ›
Generally, it is essentiall on the side where you fastenning the connection (whether it's a bolt or nut). Often used on both sides, if you (for any reasons) cannot prevent the other side from turning while fastenning. It's to prevent surface damage (especially to any possible surface treatment).Does washer go under screw or nut? ›
Before a threaded fastener (such as a screw) is driven into a surface, a washer may be placed through the end for greater protection. This prevents the bolt head and nut from scratching or indenting the surfaces of the two fastened parts, which could ultimately loosen the fastener.Which side of bolt does washer go? ›
Washer should always go on the bolt side, grip washer, flat washer or spring washer. This is if bolt is being driven into the fixed nut, and if nut is being threaded into the fixed bolt then it is spring and washer on top of it nut.Why does my nut and bolt keep loosening? ›
Spontaneous loosening, or rotational self-loosening, is essentially when a bolt rotates loose due to shock, vibration or dynamic loads. Even a slight rotation can be enough for a bolted joint to lose all its preload. This is the most common cause of bolt loosening.Why does my bolt keep coming loose? ›
Self-loosening is caused by any type of dynamic load, such as vibration or changes in temperature, insufficient clamp load and poorly fitting parts, allowing relative movements to increase the risk of self-loosening. These load changes lead to short-term frictionless situations where the bolt unwinds from the nut.What is the best tool to use on a tight bolt? ›
When you're dealing with really big stuck bolts, a pipe wrench might be your best option, especially if you don't own a giant set of wrenches or sockets. The long handle and aggressive jaw teeth will loosen the most stubborn bolts.How do I know what size washer to buy? ›
As a rule of thumb, bigger families (over 3 people in total) will require a 4 to 4.5 cubic feet washer for optimal effectiveness. For reference, 4 cubic feet can wash up to 16 pounds while a 4.5 cubic feet machine can wash 20 pounds of laundry.
The distance from the end to the flat part of the head determines the length. Always measure from underneath the head to the end to calculate this number.How do you match washers to bolts? ›
It is important to note that when matching a washer with a screw or a bolt, the diameter of the shaft of the screw or bolt should be matched to the inner diameter of the washer. For example, a ¾-16 bolt should be matched with a ¾ washer.
Washing machines in the medium and large capacity category are most common, so look for capacities anywhere from 3.5 to 5 cubic feet if you want a more standard washer size. Any medium or large capacity washer should easily fit regular as well as large laundry loads.
Does the thickness of a washer matter? ›
The best way to use them
If you have decided to use washers when fastening a product, you should first make sure that it's of the right thickness. This often depends on what you want the washer to do. For instance, if you want to make sure that the assembly is as tight as possible, you could use a washer that is thick.
|SAE FLAT WASHERS|