Industrial Bolts

About Industrial Bolts and Industrial Bolt Manufacturers Including: Anchor Bolts, Bolt Manufacturers, Eye Bolts, Metric Bolts, Stainless Steel Bolts & U Bolts.

Bolts are a type of fastener that has threads and utilizes a nut to secure the other end of it to a desired piece. Bolts hold two or more components together that would otherwise be separate. Industrial bolt manufacturers produce industrial bolts that are used for more high-stress industrial uses, such as construction, and as components in the creation of larger industrial parts, machines and vehicles. Most bolts are made out of varying grades of steel, but some are made with other materials, such as titanium and aluminum. They are inserted into the material in multiple ways, as well. Bolts can be engaged with the use of handheld screwdrivers, high pressure drills and allen wrenches. The nut, which attaches to the end of the shank, is almost always hexagonal in shape. The military and aircraft industries have specific bolt standards that require special anti-corrosive coatings and materials. These bolts are tested under more rigorous conditions, and therefore, are the preferred standard of the respective industries.
 
Industrial bolt manufacturers designate bolts by the major diameter of the external thread and the pitch measurement. A thread is a ridge that wraps around the outside of a cylinder in a helical pattern. The ridge itself is called the crest, while the space between the ridges is called the root. Threads are set at an angle to the axis of the bolt and slope either upward to the right (for right-hand threaded screws) or upward to the left (for left-handed threaded screws). The slope of the thread is known as the helix angle. The thread forms a V-shaped angle between the crest, called the thread angle, which is determined by fastener engineers. The distance from one crest of one thread to another crest is called the pitch and is measured along the axis of the thread with a thread pitch gauge.
 
Industrial bolts are further classified by industrial bolt manufacturers according to the type of the top portion (head). The head comes in a variety of shapes and styles that are necessary for the variety of materials, which bolts are used to secure. Flat heads have an angle of 80-82Û and are used where finished surfaces require a flush face. Round heads were commonly used in the past, but are now being replaced by newer designs, such as pan heads. Oval heads require the hole to be countersunk. Binding heads are undercut, binding and eliminating fraying of stranded wire in electrical and radio work. Truss heads, also known as “oven,” “stove” or “oval binding heads,” are used to cover large diameter clearance holes in sheet metal. Other types of heads include holt, one-way, Phillips finishing washer, washer and undercut heads.
 
To order bolts, it is necessary to know the type, the material and coating required, diameter and length. Fasteners are categorized based on their function or design and are available in different drive types. Industrial bolts can be manufactured from stainless steel, steel (the most widely used material), silicon bronze or brass. Steel is divided into grades, the most common of which are 2, 5, 8 and alloy steel. The grades are denoted on the head. Coatings include zinc plating, hot dip galvanizing and chrome. Zinc plating provides good corrosion resistance, as does chrome, though chrome is much more costly and is mainly used for its appearance. Galvanizing is a thick coating that provides superior corrosion resistance, although the thickly coated bolts are not compatible with other nuts. The diameter of bolts is expressed as either a size number or as a direct measurement. The method for measuring the length of a fastener depends on the type of head, but they are generally measured from the surface of the material to the end of the fastener.

Industrial Bolts and Industrial Bolt Manufacturers Image Provided by Superbolt, Inc.

Industrial Bolts and Industrial Bolt Manufacturers Images Provided by Elgin Fastener Group

Types of Industrial Bolts

• Aircraft bolts are made from cadmium to prevent corrosion and have threads rolled or pressed into the bolt, which make the bolt much stronger than the cut threads in a hardware bolt. Aircraft bolts are also tested in smaller batches for quality and are used primarily by the military and aircraft industries.
  
• Anchor bolts are long “L” shaped-style bolts that are set in concrete to anchor columns or other supports to a foundation.
  
• Bolt manufacturers produce bolts for various uses.
  
• Carriage bolts are bolts with a round head and are used for timber. Carriage bolts are threaded on only part of the shank and are inserted into pre-drilled holes.
  
• Expansion bolts have an attachment that expands as the bolt is driven into a surface.
  
• Eye bolts are bolts with an eye at one end in place of a standard head.
  
• Lag bolts are heavy woodscrews that have a square or hexagonal head, which is driven in by a wrench.
  
• Metric bolts are used by the international community and are measured using the metric system as their defining classification.
  
• Reduced shank bolts are bolts whose shank diameter is smaller than the normal dimensions for the bolt.
  
• Shoulder bolts are used primarily for location of pivot mounting. The shaft that is not threaded has a wider diameter, giving the bolt a shouldered appearance.
  
• Stainless steel bolts are used for applications where strength and resistance to corrosion is desired.
  
• Step lock bolts are made to resist vibration loosening. Step lock bolts have several portions of horizontal threads called steps.
  
• Stove bolts are small-sized machine bolts.
  
• U-bolts are U-shaped bars that have bolts and threads at both ends but not in the middle. U-bolts are primarily used in suspension areas of vehicles.  

Industrial Bolt and Nut Terms

Angle Controlled Tightening – A tightening method in which the surfaces are pulled together by tightening the fastener with a pre-selected (snug) torque. The nut is given an extra measured rotation, further tightening the fastener, often beyond its yield point to ensure the achievement of a precise preload.
 
Anti-Friction (AF) Coating – Dry lubricants that are comprised of suspensions of solid lubricants of small particle size, such as graphite or PTFE.
 
Anti-Seize Compound – A compound that is applied to the threads of fasteners and whose purpose depends on the application. Anti-seize compounds can prevent galling or mating surfaces, improve corrosion resistance or provide a barrier to water penetration by sealing the threads.
 
Bearing Stress – The surface pressure acting on a joint face, resulting from the clamping force applied by a fastener.
 
Black – A term that refers to the comparatively wider tolerances employed in the manufacturing of nuts and bolts, not necessarily the color of the surface finish.
 
Clamping Force – The compressive force exerted on a joint by a fastener.
 
Class of Fit – The measure of the degree of fit between mating external and internal threads. There are three main Classes of Fit for metric screw threads: fine, medium and coarse.
 
Creep – The permanent deformation of a bolt or other fastener resulting from the application of stress and heat.

Cut Threading – Forming threads on a fastener by cutting away and actually removing the unneeded metal.

Eccentricity – The degree of difference between the centers of the surface of a bolt at different points.

Fatigue Strength – The fracture resistance of bolts during subjection to stress variations.

Grip – The thickness of all materials that a bolt is designed to secure.
 
Head – The top portion of a bolt. A head also refers to the portion of a fastener that forms its largest diameter.

Joint – The material(s) that the fastener (bolt) connects together.
 
Nut – A small metal piece with a hole in the center that fits over a bolt or over the end of a bolt. Nuts are often hexagonal (6-sided) in shape.
 
Pull-Out – The amount of force required to pull the fastener out of the base material.
 
Shank – The portion of a headed fastener that lies between the head and the point.
 
Tensile Strength – The amount of longitudinal load/elongation a fastener can withstand without failure of the fastener or joint.
 
Thread – A raised helical pattern going around the shank of a bolt. The thread is measured by pitch, which is the distance from one peak of the thread to the next, expressed in mm or threads per inch.
 
Ultimate Torque – The amount of force at which a threaded fastener, an insert or nut begins to strip or otherwise fail in a joint.