In addition to the indicated grade marking, all grades, except A563 grades O, A and B, must be marked for manufacturer identification. The markings shown for all grades of A194 nuts are for cold formed and hot forged nuts. When nuts are machined from bar stock the nut must be additionally marked with the letter B. Nuts are not required to be marked unless specified by the purchaser. When marked, the identification marking shall be the grade Bolt & Screw Head Markings and What They Mean - Wilson Apr 10, 2021 · These lines indicate that the bolt is a Grade 5. Grade 5 fasteners have a minimum tensile strength of 120ksi for diameters ¼ inch through 1 inch and 105ksi for diameters over 1 inch through 1-1/2 inches. Grade 5 fasteners are considered to be medium-strength fasteners.
METRIC BOLTS MECHANICAL PROPERTIES; HEAD MARKING GRADE AND MATERIAL Nominal Size Range (mm) Min. Tensile Strength; NO MARKINGS:CLASS 4.6. Low or Medium Carbon Steel. 5mm - 68mm:225:235:400 MPa. 58015 psi. NO MARKINGS:CLASS 4.8. Low or Medium Carbon Steel. 1.6mm - 68mm:310:315:430 Mpa. 62366 psi. NO MARKINGS:CLASS 5.8. Low or Medium Bolt Head Grade/Strength IdentifiersFeb 15, 2019 · You can usually figure out the grade, or strength, of a bolt by looking at the markings on its head. English bolts (U.S.S. or S.A.E) are categorized by grade, from grade 2 to grade 8, where the grade represents inch strength. The higher the grade, the stronger the bolt. English bolts have radial lines on their head to identify the grade, or Bolt Identification Guide - First Call Auto SupplyMetal Grade. How strong is that bolt? In the case of hex head bolts, most of them come with markings. Metric bolts have numbers, standard bolts have little lines, and rusty bolts good luck.Tensile strength is is the maximum amount of stress a bolt can endure from being stretched or pulled until it fails.
Bolt Grades and Head Markings. Grade:Radial Bolt Markings:Material:Nominal Size Diameter/Inches:Proof Load psi:Tensile Strength minimum psi:Yield Strength minimum psi:Grade 2 No Radial Lines:Low or Medium Carbon Steel:1/4" to 3/4" 55,000:74,000:57,000:Over 3/4" thru 1 1/2" 33,000:60,000:36,000:Grade 5 3 Radial Lines:Medium Carbon Steel Bolt Grade Markings Coburn-MyersCarbon Steel Bolt Grade Markings. In addition to the the indicated grade marking, all grades included in this table must be marked for manufacturer identification. While hex heads are shown, grade markings apply equally to products with other head configurations. Grade Identification Marking Determining Bolt Grades and Understanding Head Markings9 rows · Identifying bolt grades and head markings for US grades 2, 5 and 8. Metric grades 8.8.,10.9 and 12.9 (socket products).
1. In addition to the indicated grade marking, all grades, except A563 grades O, A and B, must be marked for manufacturer identification. 2. The markings shown for all grades of A194 nuts are for cold formed and hot forged nuts. When nuts are machined from bar stock the Hex Bolt Identification, Markings and Strength Chart Table Grade B8M:Bolts, Screws, Studs:AISI 316-50,000 thru 95,000:90,000 thru 125,000:ASTM A193 Grade B8T:Bolts, Screws, Studs:AISI-50,000 thru 95,000:100,000 thru 120,000:SAE J429 Grade 1:Bolts, Screws, Studs:Low or Median Carbon Steel:33,000:36,000:60,000:ASTM A320 Grade L7B:Bolts, Screws, Studs, Low temp Appl. AISI 4137-105,000:125,000:ASTM A320 Grade L7C:Bolts, Screws, How to define what type of bolt youre using.The grade/class of a bolt and its manufacturer are identified on the head. Lines varying in number in different positions and numbered markings determine grading / class. The basic rule of thumb in determining the grade is to count the number of lines on head of
Eye bolt identification markings:Shoulder Nut Eye Bolt Installation for In-Line and Angular Loading:A.The threaded shank must protrude through the load sufficiently to allow full engagement of the nut. B.If the eye bolt protrudes so far through the load that the nut cannot be tightened securely against the load, use properly sized washers to take up the excess space BETWEEN THE NUT AND Socket head cap screw markings Fasteners, bolts, screws Socket head cap screw markings. Inch has one strength level, alloy steel. Metric has two strength levels, property classes 12.9 and 8.8. 8.8 is about 30% weaker. 8.8 is also 20 50% less expensive. Caution:Dont substitute 8.8 for 12.9. For metric M5 and larger, the property class and manufacturers I.D. is marked on the head.Standard Inch Grade ID Markings - AALL American Bolts 307AASTM A307 Grade A Bolts, screws, studs (general engineering) Low or medium carbon steel 1/4 - 4 33000 60000 36000 B69 B100. 307BASTM A307 Grade B Bolts, screws, studs (flanged joints) Low or medium carbon steel 1/4 - 4 33000 60000 36000 B69 B95. Note:Manufacturers identification mark also stamped where appropriate.