The three dashes on a bolt usually means that it is a recommended bolt. This is usually seen on structural connections and indicates that the bolt should be tightened more as it will be used in a heavily loaded situation.
The three dashes are known as K factor marking, which is used to help the user select the most suitable bolt for the job. The three dashes represent a K factor of 75%. In terms of tightness, this is considered to be quite tight.
When installing a bolt with this marking, follow the recommendations for tightening torque and allow some extra tightening to ensure that the bolt is properly secure. Depending on the nature of the connection, other factors such as lubrication, pre-load and thread dry lubrication should also be considered.
What are the dash marks on bolts?
Dash marks are often seen on nuts and bolts and serve to identify the grade of the material used to make the bolt. The number of dashes indicate the strength and durability of the bolt and nut, with three dashes indicating the lowest grade, and six dashes indicating the highest grade.
For example, a three dash bolt is softer than a six dash bolt and thus has a lower tensile strength.
Bolts and nuts with different grades of strength are used for different applications. For example, higher grades of bolts might be used for applications that require a tighter tolerance or need to withstand multiple tightening and loosening cycles, like a car engine.
Lower grades of bolts are usually used in applications that require less torque and tensile strength, like furniture or equipment.
Using the wrong grade of bolt can lead to over- or under-tightening, damaging the nut and bolt surface or compromising the quality of the application. It is important to use the right grade of bolt when working on a project or working with machinery, as it ensures that the right level of torque will be applied to secure and maintain the application.
What type of bolt has a single dash on the head?
A socket head cap screw is a type of bolt that has a single dash on the head. These screws are commonly used in applications where added strength and a low profile are needed. They feature a cylindrical head with a raised section in the center, which contains the single dash marking.
The head is designed for use with a socket wrench and is typically made from hardened steel. Socket head cap screws are available in many different sizes and lengths to meet a variety of fastening needs.
They can be used in construction, repair, and fabrication projects.
What is a bolt with a raised dash?
A bolt with a raised dash, also known as a torque-to-yield (TTY) bolt, is a special type of bolt that stretches a small amount when tightened in order to maintain a consistent amount of pre-load tension.
This pre-load tension creates the desired clamping force in the bolted joint which aids in creating a secure and lasting connection. The raised dash indicates that it is a TTY bolt, with the raised portion of the dash visible after tightening.
TTY bolts are typically used to join cylinder heads to engine blocks or connecting rods to crankshafts as they provide an even and consistent tension on the joint, enabling the bolts to stay securely fastened over time.
How many slashes does a Grade 6 bolt head have?
A Grade 6 bolt head typically has two slashes across the bolt head, forming an ‘X’. Grade 6 bolts are a type of a medium strength steel bolt that often has a hexagonal head for tightening. It is usually used for low temperature joining and typically has six evenly spaced lines on the top of the head in a radial fashion.
It is a common type of bolt used in many applications.
What is a Cuphead bolt?
A Cuphead bolt is a type of lightning bolt from the popular video game Cuphead. The bolts are a huge part of the game and they come in various colors and shapes. They are best known for their appearance as an enemy in the game.
These bolts are fired off by enemies when they’re defeated and have to be collected to increase Cuphead’s health. Collecting Cuphead bolts also adds to the tally at the end of each level, thus increasing the overall score.
Apart from being used to increase Cuphead’s health and score, these bolts also power up special abilities such as the ability to supercharge a dash or launch a super attack. All in all, Cuphead bolts are an important and iconic part of the game which adds to the overall experience.
What are the screws called with one line?
The screws are called Phillips head screws, named after its inventor Henry F. Phillips.
Why do Grade 5 bolts have 3 marks?
Grade 5 bolts are marked with three distinct radial lines on the head of the bolt. These marks indicate the strength of the material that the bolt is composed of. Grade 5 bolts are made from medium carbon steel which is heat treated to a minimum of 120,000 PSI (pounds per square inch) of tensile strength.
The three lines symbolize that minimum tensile strength rating and make it easy to differentiate Grade 5 bolts from other grades. Grade 5 bolts are designed for general purpose use, such as fastening wood or metal structures, and are suitable for most projects.
Their increased strength over lower grades makes them more suitable for the added stress and load of larger, heavier projects.
How do you read a bolt code?
Bolt codes are meant to be intricate and abstract, yet easy to interpret. To read a bolt code, you first need to identify the bolt’s diameter and thread count. Once you have determined the size of the bolt, you can then look at the code printed on the bolt.
Most of the time, there will be a series of numbers or letters etched into the head of the bolt itself.
These numbers and letters indicate the material, grade and type of bolt, as well as its head style and diameter. The numbers can also tell you the thread count. For instance, a 5/16-18 type bolt has 18 threads per inch and is 5/16 of an inch in diameter.
The beginning of the bolt code usually indicates the length of the bolt and the pattern of the thread. The number after the length gives information about the grade of alloy used in the bolt. Grade 5 bolts will have a 3, whereas Grade 8 bolts will start with a 4.
Once you have determined the grade of the bolt, these are the numbers and letters commonly used to indicate the material and finish of the bolt:
• 18-8 (304 stainless steel)
• B-7 (heat-treated medium carbon alloy steel)
• Grade 5 (heat-treated alloy steel)
• Grade 8 (heat-treated alloy steel)
• Zinc
• Red Brass
• Black Oxide
Something to keep in mind is that bolt codes can differ between manufacturers, so it is important to be aware of the specific bolt code for the manufacturer you are working with. Additionally, it can be helpful to keep a chart of known bolt codes handy for reference.
How can you tell the difference between Grade 5 and Grade 8 bolts?
Grade 5 bolts are made of medium carbon steel and are somewhat stronger than Grade 2 bolts. They are usually identified by the marks “Grade 5” or “Class 8.8” and the head of the bolt will usually have six radial lines around it.
Grade 8 bolts are made of a medium-alloy steel and are stronger and more impact resistant than Grade 5 bolts. They are usually identified by the marks “Grade 8” or “Class 10.9” and the head of the bolt will usually have eight radial lines around it.
Grade 8 bolts are always black, whereas Grade 5 bolts can be black or yellow zinc. Grade 8 bolts are also required for use in high-stress applications, such as suspension systems, while Grade 5 bolts are often used in more general applications.
Is Grade 8 or 12.9 stronger?
The answer to this question depends on what material is being used. Generally, Grade 8 bolts are stronger than 12.9 bolts, as the higher the grade number, the stronger the strength of the bolt. Grade 8 bolts have a tensile strength rating of 150,000 psi (pounds per square inch), while 12.9 bolts have a tensile strength rating of 170,000 psi.
This means that Grade 8 bolts can withstand a greater force before they break. However, 12.9 bolts are more resistant to corrosion, making them the more ideal choice for use in corrosive environments.
Ultimately, the best material to choose will depend on the application and environment in which it will be used.
Is there a Grade 10 bolt?
Yes, there is a Grade 10 bolt. Grade 10 bolts are made from a medium-carbon steel that has been quenched and tempered, among other steps. A Grade 10 bolt has a property class of 10.9 which means that the yield strength is at least 830 MPa and the tensile strength is at least 1040 MPa.
Grade 10 bolts are typically used in construction applications, such as columns, beams, and other connections. They are also often used in automotive applications and to attach parts to fixtures. Grade 10 bolts are resistant to most weather conditions, corrosion, and other agents.
They require no special coating and can be fastened with most common bolts.
What is the hardest bolt you can buy?
The hardest bolt you can buy is likely one that is made from hardened tool steel. These bolts are created through a process called hardening, which is when a material is heated and then cooled rapidly in an effort to create a more durable and tougher surface.
Hardened steel bolts are often used in industrial applications that require higher strength and greater resistance to wear than an ordinary bolt. They generally require special tools to install, since their increased hardness means they are much more difficult to work with than a standard bolt.
In some cases, they may even require screws or rivets to be used in place of bolts.
What grade is stronger than 8?
Grade 8 steel is a type of mild steel and is often referred to as “structural steel.” It has a yield strength of 35,000 psi, tensile strength of 58,000 to 80,000 psi, and Brinell hardness of 125. Grade 8 steel is one of the most common grades of steel and is used for countless applications.
Grade 8 steel is stronger than many other steels and it is commonly used to make structural components in a variety of industries. Grade 8 steel can also be found in automotive, agricultural, and oil & gas applications.
Grade 8 steel is significantly stronger than grade 8 steel and it is typically used in applications requiring increased strength or wear resistance. Grade 8 steel has a yield strength of 130,000 psi, tensile strength of 150,000 psi, and Brinell hardness of 270.
It is much more difficult to work with than grade 8 steel and is typically used primarily in applications requiring very high strength. Grade 8 steel is commonly used to make heavy duty components such as bulldozers, cranes, and excavators, as well as other tools requiring exceptional strength and durability.
How strong is a Grade 12.9 bolt?
Grade 12.9 bolts are considered to be the strongest type of bolts commercially available. These bolts are made from a heat treated steel alloy, and they have an ultimate tensile strength of 180,000 to 190,000 psi.
This makes them roughly 20-25% stronger than grade 8, which typically has a tensile strength of 150,000 psi. Grade 12.9 bolts are frequently used in applications where very high clamping force is required, such as high-pressure hydraulic systems, or in heavy-duty machinery.
They can withstand extreme conditions, and they typically have high fatigue strengths. In summary, Grade 12.9 bolts offer the highest level of strength, durability, and reliability available on the market.