| 1 | Base Material | Confirm the steel or stainless-steel grade, chemical composition, heat treatment, and suitability for the service environment. | Carbon steel is widely used for general construction. Stainless steel grades such as 304 and 316 are selected for improved corrosion resistance. Grade 316 generally performs better than 304 in chloride-bearing environments because of its molybdenum content. | Do not specify “stainless steel” without naming the grade. Match the material to humidity, salt exposure, chemicals, temperature, and contact with dissimilar metals. |
| 2 | Strength Grade | Verify the applicable standard, tensile strength, yield or proof strength, and whether the bolt, nut, and washer grades are compatible. | ISO metric property classes commonly include 8.8, 10.9, and 12.9. Class 8.8 has a nominal tensile strength of 800 MPa and a nominal yield ratio of 0.8; exact requirements depend on the governing standard. | Higher strength is not automatically better. Use the structural engineer’s design values and avoid pairing high-strength bolts with unsuitable nuts or washers. |
| 3 | Anchor Type and Geometry | Identify whether the product is a cast-in anchor bolt, headed bolt, bent anchor, sleeve anchor, wedge anchor, or chemical anchor system. Check diameter, embedment, thread length, projection, and bend dimensions. | Cast-in anchors transfer load through embedment, heads, plates, hooks, or bends. Post-installed anchors rely on mechanical expansion or a qualified adhesive system. | The anchor type must match the concrete condition, installation sequence, edge distance, spacing, cracked or uncracked concrete, and design load direction. |
| 4 | Diameter and Load Capacity | Check tension, shear, combined loading, effective embedment depth, concrete strength, edge distance, spacing, and steel failure modes. | Nominal bolt diameter alone does not determine capacity. Concrete breakout, pullout, pry-out, splitting, and steel fracture can govern the design. | Request a design calculation or tested load data for safety-critical applications. Do not compare products only by outside diameter or published ultimate load. |
| 5 | Thread Standard and Tolerance | Specify metric or inch threads, nominal diameter, pitch or threads per inch, thread class, thread length, and nut compatibility. | Metric coarse threads are common in international projects, while fine threads may be selected for specific adjustment or locking requirements. Thread tolerances must be compatible with the mating nut. | Provide a complete thread callout on the purchase order. Mixing metric and inch components can cause assembly failure and permanent thread damage. |
| 6 | Corrosion Protection | Evaluate the coating type, coating thickness, surface preparation, service environment, and risk of hydrogen embrittlement for high-strength fasteners. | Common options include electroplated zinc, hot-dip galvanizing, mechanical galvanizing, zinc-flake coatings, and stainless steel. Hot-dip galvanizing generally provides a thicker zinc layer than electroplating, but dimensional and thread considerations apply. | Select the coating based on exposure, not appearance. Confirm coating compatibility with the nut, required torque, thread allowance, and local environmental regulations. |
| 7 | Environmental Exposure | Classify the installation as indoor, outdoor, coastal, marine, industrial, underground, or exposed to chemicals, de-icing salts, or constant moisture. | Atmospheric corrosivity increases with moisture, chlorides, pollutants, and time of wetness. Crevices and water-trapping details can accelerate localized corrosion. | For severe chloride exposure, compare a suitable stainless grade or engineered coating system instead of relying on standard zinc plating alone. |
| 8 | Standards and Traceability | Request the applicable product standard, material certificate, heat or lot number, inspection records, and dimensional and mechanical test results. | Common reference systems include ISO, ASTM, EN, and national construction standards. Requirements differ by product type, material, coating, and application. | A certificate should identify the actual supplied lot and test results, not only state that the product is “standard compliant.” Confirm acceptance with the project specification. |
| 9 | Installation and Pretension | Check hole diameter, drilling method, cleaning procedure, curing time for adhesive systems, tightening method, torque requirements, and installation temperature. | Torque is affected by friction, lubrication, coating, thread condition, and washer type. Torque alone does not guarantee a specific preload unless the relationship has been validated. | Provide installation instructions with the shipment. For critical connections, use a calibrated method and document inspection results. |
| 10 | Packaging, Logistics, and Inspection | Review packaging strength, corrosion protection during transport, labeling, quantity control, delivery documents, sampling plan, and dimensional inspection requirements. | Anchor bolts are vulnerable to thread damage, mixed lots, coating abrasion, and moisture exposure during storage and shipment. | Use capped or protected threads where appropriate, sealed packaging for humid routes, clear lot labels, and pre-shipment inspection for dimensions, coating condition, grade marking, and quantity. |