AISI is an acronym for American Iron and Steel Institute. AISI members make over 80% of the steel produced in North America. AISI sets standards for steel companies around the U.S. in a push to improve the industry.
All Thread All thread rod is a piece of rod that has been threaded for its entire length. All thread rod is used for general purpose fastening for anything from an anchor bolt to a through bolt. All thread rods that are less than 12 inches are called studs. All thread rods that are 12 inches and longer are called threaded rods.
Alloy Steel Alloy steel is steel that is alloyed (mixed) with a variety of elements to improve its mechanical properties. Common alloyants include manganese (the most common one), nickel, chromium, molybdenum, vanadium, silicon, and boron. Improved properties in alloy steels (as compared to carbon steels): strength, hardness, toughness, wear resistance, corrosion resistance, hardenability, and hot hardness. One alloy steel—AISI-4140 when heat treated becomes B7.
Aluminum is a basic element. AATP makes threaded products from aluminum. A common use of these products is exterior products.
Anchor Bolt An anchor bolt is used to attach objects or structures to concrete. Anchor bolts consist of a threaded end, to which nut and washer can be attached for the external load. Usually anchor bolts are bent at one end; however, they also can be straight. Anchor bolts are extensively used on all types of projects.
ASTM American Society for Testing and Materials, is a leading standards development organization. Portland Bolt participates as a voting member on ASTM Committee F16 on Fasteners. This committee has jurisdiction on over 60 fastener standards.
Black Oxide is a protective surface formed by a chemical reaction with the iron in the metal. The finish is sealed with oil, once the oil is gone the product will begin to rust rapidly.
Brass is an alloy made of copper and zinc. AATP makes threaded products from brass. A common use of these products is exterior.
Chamfer is a conical surface at the starting end of a threaded rod. A grinding process (See Stud Master) removes the first thread to create a fastener that easily accepts a nut. The first thread can easily be damaged in packaging, shipping, or general handling in the field and by removing it, we ensure the fit of the nut.
Coarse Threads (primarily defined by thread pitch) is a group of products also known as UNC. Coarse threads are the most popular thread group at AATP. In 1948 the Unified Thread Standard was developed to unify threads produced in the UK, Canada and the US. The three primary groups of the Unified Thread System are Unified National Coarse (UNC), Unified National Fine (UNF), and Unified National Extra Fine (UNEF).
Copper is soft and malleable and has very high thermal and electric conductivity. AATP makes 3/4” threaded products from copper. These products are commonly used in the electrical industry.
Coupling Nut also known as an extension nut, is a threaded fastener for joining two threaded rods. The outside of the fastener is usually hex, giving a wrench the ability to hold it. The threaded rod is threaded into the coupling nut for a certain distance.
Draw Straight and Cut is where the draw-straight-cut (DSC) machine takes green wire coils and draws the wire into a uniform diameter, then straightens it and finally cuts it to a desired length. The straight-cut (SC) machines are similar; however, they start with wire on hats that has already been drawn.
Green Wire Coil is a long single strand of steel that is coiled up into bundles. The steel will be straightened then threaded to eventually make anchor bolts, threaded rod, threaded studs, u-bolts, etc. Green wire coil is hot rolled wire rod supplied prior to having the material cleaned and coated, drawn or annealed. AATP prefers to buy low carbon steel as green rod so they do their own processing once.
Heat Treatment is a group of industrial and metalworking processes used to alter the physical properties of a material. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve a desired result such as hardening or softening a material. B7 steel is heat treated.
Hot Dip Galvanizing (HDG) is the process of dipping steel products into a kettle or vat containing molten zinc. The process is inherently simple which provides an advantage over other corrosion protection methods. Threaded rod is dipped to protect the steel from rusting in outdoor conditions.
Kitted Anchor Bolts are cartons of anchor bolts, washers and nuts. An anchor bolt is used to attach objects or structures to concrete. Anchor bolts consist of a threaded end, to which nut and washer can be attached for the external load. Anchor bolts are extensively used on all types of projects, from standard buildings to dams.
Knurling is a manufacturing process whereby a pattern of straight, angled or crossed lines is cut or rolled into the material.
Low Carbon Steel (or mild) steel is the most common type of steel used for general purposes, in part because it is less expensive than other types of steel. Typically, it has a carbon content that ranges between 0.05% and 0.30%. Low carbon steel contains properties that work well in manufacturing a variety of goods.
Master Product List (MPL) is the list of items (SKU’s) that we have decided to stock at AATP. Sales has predetermined sales prices (based on quantity) for each item. Operations has predetermined minimum and maximum stock levels for each item. The different AATP divisions have different Master Product Lists.
Medium Carbon Steel is based on the amount of carbon inside of the steel during manufacturing. The AISI classifies medium carbon steel as anything with 0.25% to 0.60% carbon content. Medium carbon steel has great strength and does not wear easily. Some types are:
Metric is the (European) measurement system that is based on the power of ten — using millimeters, centime-ters and meters. Often used in the USA by manufactures with global distribution— i.e. Caterpillar. A threaded rod with the designation:
12 millimeter pitch diameter
1.75 millimeter thread pitch
1 meter in length
Passivate/Passivation is an outsourced cleaning process. The passivation process returns stainless steel or other metals back to their original specifications by removing unwanted debris and oils from the surface. When a part is machined, various particles can permeate the surface of the base metal, weakening it’s resistance to corrosion and making the part more susceptible to environmental factors.
Pitch Diameter of a particular threaded part is the diameter of a cylindrical surface, which creates a line that passes through and intersects the thread flanks at equal points around the threaded product.
Plain/Oil Finish refers to steel threaded products that only have a bit of oil from the threading process. No cleaning and/or plating has been done to the product after threading.
Restriction of Hazardous Substances (RoHS) aims to restrict certain dangerous substances commonly used in electronic and electronic equipment. The dangerous substances include, lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls, and polybrominated diphenyl ethers. In regards to AATP, RoHS compliant would pertain to the plating of our products.
Roll Threading is a process by which steel is extruded to form the threaded portion of a fastener, instead of being removed as in cut threading. (In this process, a bolt.) Threaded rod or stud is manufactured from a reduced diameter round bar. The part is rolled through a set of threading dies which displaces the steel and forms the threads.
Rounds pieces of steel that have been straightened and cut to length. AATP will sell rounds in this form; however, most rounds will be either bent or threaded.
Ruja Bender is a machine that holds one end of a rod while the other end bends the rod to the desired shape. This machine can be used to bend anchor bolts, j-bolts, eye bolts and u-bolts.
SAE International was initially established as the Society of Automotive Engineers and has evolved into a standards organization for engineering professionals. SAE is involved in efforts to standardize such numbering system for steel. SAE used to be partnered with AISI but AISI handed over the job and now only SAE makes the standards for the steel industry
Shear is the process of “chopping” off a piece of bar stock. We shear drawn bar stock as the final step of the DSC process. We also have shear machines that take WIP bar stock and chop to length prior to threading. The alternative is to saw rather than shear.
Silicone Bronze is a low-lead material that is mainly composed of copper, the rest of the material is silicone. Silicone bronze has very good corrosion resistant properties.
Single-End Rods and Studs have threads at one end and the balance of the rod unthreaded. All AATP single end products are Specials.
Specials (SP) are AATP items that are not on the Master Product List; therefore, we do not carry inventory. Each special is priced and costed at the time of quoting based on size, order quantity and required tolerances.
Stainless Steel is steel that contains chromium (12% +) and is much more resistant to corrosion, rust and stain than low carbon steel. There are several different types of stainless steel. AATP produces threaded products from SS304 (the most common form) which is also know as 18-8 (18% chromium—8% nickel). AATP also produces some products from SS316 (aka as marine grade) containing molybdenum which prevents specific forms of corrosion.
Stock Specials (SS) are AATP items that are specials; however, a customer has committed to purchase them from us on a regular basis. Therefore, we will keep in inventory an agreed upon quantity of the stock special. Stock specials are only available for sale to the designated customer.
Stud Master is a hand fed chamfering machine which creates the chamfer at the end of either threaded products or bar stock.
Studs are threaded rod that are less than 12 inches in length. Studs can be all thread, double-end studs or single-end studs.
Thread Classes describes the looseness or tightness of fit between external threads (rods) and internal threads (nuts.) For Unified, imperial (inches/ feet) items, there are three types of thread classes—1A, 2A, and 3A.
For metric items, there are three types of thread classes—2g, 4g, and 6g. The 6g is the most popular metric thread class and roughly equivalent to 2A.
Thread Pitch is a measurement of the distance from one thread to the next. For Unified—imperial (inches/ feet) items, the thread pitch is defined by the number of threads per inch. For metric (millimeters/ meters) items the thread pitch is defined by the distant in millimeters between two threads.
Threaded Rod is defined as straight rod that is 12 inches and longer in length. AATP produces threaded rod up to 12 feet in length. Threaded rod can be all thread, double-end or single-end thread.
USS Flat Washer is a thin plate (typically disk-shaped) with a hole (typically in the middle) that is normally used to distribute the load of a threaded as a screw or nut. Common materials include steel, stainless steel, and plastic.
Work In Progress (WIP) are partially finished goods wait-ing for completion and eventual sale These items are either just being fabricated or waiting for further process-ing in a line.
Zinc Plating is a thin coating applied to finished products. Zinc’s excellent corrosion resistance in most environments accounts for its successful use as a protective coating in many exposure conditions. The plating process includes cleaning, rinsing and then a bath in zinc solution with an electric current applied. Zinc coating comes in two different colors—clear, and yellow. AATP’s most common zinc coating is clear—which brightens the steel and may have a slight blue tint. Yellow (sometimes called yellow chromate) is a more robust plating. Yellow is AATP’s default color for zinc plated B7.
We are a prime U.S. manufacturer of a wide range of quality threaded products with facilities in Denver, Colorado and Lancaster, Pennsylvania.