Newest FAQs
Galvanized Bolts and Chased Threads
Can threads be chased after hot-dip galvanizing for proper nut fit?Absolutely not! Externally threaded fasteners should never be “chased”. During the hot-dip galvanizing process, excess zinc has a tendency to build up in the threaded portion of a fastener. Chasing threads is a term used to describe re-cutting threads after galvanizing to remove this excess zinc that has accumulated during the galvanizing process. Chasing threads... Read more
SAE Grade 8 markings
What visual markings does a grade 8 piece of all thread rod have that would identify it as being so? Meaning, how can you tell just by looking at a stick that it's grade 8?Most grade 8 bolts require a permanent marking symbol that is designated by 6 radial lines. However, the SAE J429 specification that covers grade 8 fasteners does not require grade markings for studs (fully threaded rods) or slotted and cross recess head products. Therefore, you will not be able to visually identify a threaded stud... Read more
Thread Engagement
How much thread engagement is recommended, i.e. how many threads should extend beyond the nut?This is a difficult question to answer. Depending on your application, the answer could be anywhere from 1/2 engagement, up to having two full threads extend beyond the nut. Look at these conflicting answers found in four separate technical publications. Federal Highway Administration, “Guidelines for the Installation, Inspection, Maintenance and Repair of Structural Supports for... Read more
Weight Gained from Galvanizing
How much weight is gained from hot-dip galvanizing bolts?According to the American Galvanizers Association (AGA) the weight of an item on average will increase about 3.5% from the zinc added during the galvanizing process. However, the AGA goes on to say, “…that figure can vary greatly based on numerous factors. The fabrication’s shape, size, and steel chemistry all play a major role, and... Read more
High Strength Bolts Coatings
What corrosion-resistant coatings are available for high-strength (over 150 ksi) bolts?Due to hydrogen embrittlement concerns ASTM recommends against hot-dip galvanizing , mechanical deposition, or electroplating with zinc or other metallic coatings on high strength bolts ultimate tensile strengths that exceed 150 ksi. So what are the alternatives to provide corrosion resistance for A490 structural bolts? Protective Coatings ASTM states that if a protective coating is... Read more
ASTM and SAE Differences
What are the main difference between ASTM 307 GR.B, ASTM A449, and SAE Grade 5 bolts?There are two specifying bodies when it comes to fasteners. ASTM (American Society for Testing and Materials) covers primarily bolts and fasteners for construction applications. SAE (Society of Automotive Engineers) covers fasteners for automotive, machinery, and OEM applications. ASTM A307 grade B is made from a low carbon steel and is a relatively low strength... Read more
Bolt Thread Length
Is there a standard thread length for bolts?Depending on the type of bolt you are using the thread length can vary greatly. There is not an inclusive thread length standard that covers all fasteners. Depending on the applications, manufacturer, and a number of other factors the amount thread may change. It is important to clearly communicate at time of purchase your desired... Read more
Guidelines for Ordering U-Bolts
I need to buy some non-standard size u-bolts. Do you have any guidelines that will help me with ordering the u-bolts I need from Portland Bolt?Portland Bolt can manufacture custom u-bolts that are made from 1/2” diameter and larger steel. So as long as the u-bolts you need are 1/2” in diameter or larger, we can most likely manufacture them, within the capabilities of our bending equipment and the limitations of the steel itself. To better understand what can be... Read more
Tie Rod Assembly Configurations
How are tie rods, turnbuckles, and clevises configured?Tie rods, clevises, and turnbuckles are an important part of many architectural designs. Canopy supports, structural steel bracing, and walkway hangers are a few of the applications that use these assemblies. The unique configuration allows for field adjustments in both length and tension. Adjustment Adjustments are possible by threading opposing ends of the rod right hand... Read more
ASTM A325 vs A449
I have two items that use 1" bolts, one is ASTM A325 and the other is ASTM A449, I would like to just use one. Which is the one that meets or exceeds the other?These bolts are identical with regard to strength and chemistry. There are very minor differences in the hardness requirements, but the proof load, tensile, and yield strength requirements are the same. From a manufacturing standpoint, we make these bolts using the same raw material and the same heat treating and production methods. Our strength by... Read more