{"title":"DIN 603 Carriage Bolt 8.8 Hot Dip Galvanized","description":"\u003ch1\u003eDIN 603 Carriage Bolt — Grade 8.8 | Hot Dip Galvanized | FULLERKREG\u003c\/h1\u003e\n\n\u003cp\u003eFULLERKREG DIN 603 Grade 8.8 Hot Dip Galvanized Carriage Bolts combine the high clamping strength of Grade 8.8 with the unmatched long-term corrosion protection of hot dip galvanizing — making them the definitive choice for heavy structural timber connections, civil infrastructure, and outdoor load-bearing applications exposed to weather, moisture, and corrosive environments. Manufactured from Alloy Steel 10B21 (boron steel) or Carbon Steel 35K, these bolts deliver both the mechanical performance and the environmental durability demanded by the most challenging structural applications.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStandard:\u003c\/strong\u003e DIN 603\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCommon Name:\u003c\/strong\u003e High-Strength Carriage Bolt \/ Coach Bolt \/ Round Head Square Neck Bolt\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Alloy Steel 10B21 (boron steel) or Carbon Steel 35K\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eProperty Class \/ Grade:\u003c\/strong\u003e 8.8 (per DIN EN ISO 898-1)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSurface Treatment:\u003c\/strong\u003e Hot Dip Galvanized (HDG)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread:\u003c\/strong\u003e Metric coarse thread (ISO 68-1)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHead Type:\u003c\/strong\u003e Round (domed) head with square neck\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e FULLERKREG\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eWhat Is a DIN 603 Carriage Bolt?\u003c\/h2\u003e\n\u003cp\u003eThe DIN 603 carriage bolt — also known as a coach bolt or round head square neck bolt — is a specialized fastener defined by three key geometric features:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSmooth Domed Head:\u003c\/strong\u003e The low-profile, rounded head presents a clean, tamper-resistant appearance on the visible face of the joint. No drive recess is present — the bolt is tightened exclusively from the nut side, leaving a smooth, snag-free surface.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSquare Neck (Collar):\u003c\/strong\u003e Immediately below the head, a short square section embeds into the timber substrate or a pre-punched square hole when the nut is tightened, preventing the bolt from rotating. This enables single-sided tightening with a wrench on the nut alone.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThreaded Shank:\u003c\/strong\u003e The shank carries a metric coarse thread accepting a standard hex nut or flange nut. Shorter lengths may be fully threaded; longer lengths feature an unthreaded grip section.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eWhy Grade 8.8?\u003c\/strong\u003e The Grade 8.8 variant delivers approximately double the tensile strength of the standard Grade 4.8 carriage bolt (800 MPa vs 420 MPa), making it the preferred choice for heavy structural timber connections, civil engineering joints, and load-bearing applications where higher clamping forces are required.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhy Hot Dip Galvanized?\u003c\/strong\u003e HDG provides a metallurgically bonded zinc coating of 45–85 µm — far thicker than electroplated alternatives — delivering decades of outdoor corrosion protection with self-healing cathodic protection properties. The combination of Grade 8.8 strength and HDG durability makes this the premium specification for permanent outdoor structural fastening.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eMaterial Options\u003c\/h2\u003e\n\n\u003ch3\u003eOption A — Alloy Steel 10B21 (Boron Steel)\u003c\/h3\u003e\n\u003cp\u003e10B21 is a boron-alloyed low-carbon steel widely used in high-volume structural fastener production. The boron addition (0.0005–0.003%) significantly improves hardenability, allowing Grade 8.8 mechanical properties to be achieved with excellent cold-forging characteristics and consistent lot-to-lot quality.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCarbon Content:\u003c\/strong\u003e ~0.18–0.23% C\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBoron Addition:\u003c\/strong\u003e 0.0005–0.003% B — dramatically improves hardenability\u003c\/li\u003e\n  \u003cli\u003eSuperior hardenability vs plain carbon steel — consistent Grade 8.8 properties across large cross-sections\u003c\/li\u003e\n  \u003cli\u003eExcellent cold-heading formability — ideal for high-volume production\u003c\/li\u003e\n  \u003cli\u003eLow carbon content ensures good HDG zinc adhesion and minimizes risk of embrittlement during galvanizing\u003c\/li\u003e\n  \u003cli\u003ePreferred material for structural OEM and Tier-1 supply chains\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eOption B — Carbon Steel 35K\u003c\/h3\u003e\n\u003cp\u003e35K is a medium-carbon steel offering a reliable balance of strength and toughness at an economical cost. Suitable for Grade 8.8 fasteners in general structural and civil engineering applications.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCarbon Content:\u003c\/strong\u003e ~0.32–0.39% C (medium carbon)\u003c\/li\u003e\n  \u003cli\u003eGood balance of tensile strength and ductility for Grade 8.8 requirements\u003c\/li\u003e\n  \u003cli\u003eCost-effective for high-volume structural fastener applications\u003c\/li\u003e\n  \u003cli\u003eSuitable for non-critical structural joints and general heavy-duty assembly\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNote:\u003c\/strong\u003e Higher carbon content requires careful control of pickling and galvanizing process parameters to avoid hydrogen embrittlement and ensure coating adhesion\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eMechanical Properties — Grade 8.8\u003c\/h2\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eProperty\u003c\/th\u003e\n      \u003cth\u003eSpecification\u003c\/th\u003e\n      \u003cth\u003eStandard Reference\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMaterial\u003c\/td\u003e\n      \u003ctd\u003eAlloy Steel 10B21 or Carbon Steel 35K\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eProperty Class\u003c\/td\u003e\n      \u003ctd\u003e8.8\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eNominal Tensile Strength (Rm)\u003c\/td\u003e\n      \u003ctd\u003e≥ 800 MPa\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eProof Load Stress (Sp)\u003c\/td\u003e\n      \u003ctd\u003e600 MPa\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYield Strength (Rp0.2)\u003c\/td\u003e\n      \u003ctd\u003e≥ 640 MPa\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eHardness (Vickers)\u003c\/td\u003e\n      \u003ctd\u003e250 – 320 HV\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCore Hardness (Rockwell)\u003c\/td\u003e\n      \u003ctd\u003e22 – 32 HRC\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eElongation after fracture\u003c\/td\u003e\n      \u003ctd\u003e≥ 12%\u003c\/td\u003e\n      \u003ctd\u003eDIN EN ISO 898-1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eSurface Treatment\u003c\/td\u003e\n      \u003ctd\u003eHot Dip Galvanized (HDG)\u003c\/td\u003e\n      \u003ctd\u003eISO 1461 \/ EN ISO 10684\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eZinc Coating Thickness\u003c\/td\u003e\n      \u003ctd\u003e≥ 45 µm (typical 50 – 85 µm)\u003c\/td\u003e\n      \u003ctd\u003eISO 1461\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCorrosion Resistance (NSS)\u003c\/td\u003e\n      \u003ctd\u003e≥ 1,000 hours neutral salt spray\u003c\/td\u003e\n      \u003ctd\u003eISO 9227\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eGrade Comparison: 4.8 vs 8.8 (HDG)\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eProperty\u003c\/th\u003e\n      \u003cth\u003eGrade 4.8 HDG\u003c\/th\u003e\n      \u003cth\u003eGrade 8.8 HDG (This Product)\u003c\/th\u003e\n      \u003cth\u003eImprovement\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eTensile Strength (Rm)\u003c\/td\u003e\n      \u003ctd\u003e≥ 420 MPa\u003c\/td\u003e\n      \u003ctd\u003e≥ 800 MPa\u003c\/td\u003e\n      \u003ctd\u003e+90%\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYield Strength (Rp0.2)\u003c\/td\u003e\n      \u003ctd\u003e≥ 340 MPa\u003c\/td\u003e\n      \u003ctd\u003e≥ 640 MPa\u003c\/td\u003e\n      \u003ctd\u003e+88%\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eProof Load Stress (Sp)\u003c\/td\u003e\n      \u003ctd\u003e310 MPa\u003c\/td\u003e\n      \u003ctd\u003e600 MPa\u003c\/td\u003e\n      \u003ctd\u003e+94%\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eHDG Coating Thickness\u003c\/td\u003e\n      \u003ctd\u003e≥ 45 µm\u003c\/td\u003e\n      \u003ctd\u003e≥ 45 µm\u003c\/td\u003e\n      \u003ctd\u003eEqual\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eOutdoor Service Life\u003c\/td\u003e\n      \u003ctd\u003e20–50+ years\u003c\/td\u003e\n      \u003ctd\u003e20–50+ years\u003c\/td\u003e\n      \u003ctd\u003eEqual\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eTypical Use\u003c\/td\u003e\n      \u003ctd\u003eLight-to-medium structural timber\u003c\/td\u003e\n      \u003ctd\u003eHeavy structural, civil engineering, load-bearing\u003c\/td\u003e\n      \u003ctd\u003e—\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eHot Dip Galvanizing: Process \u0026amp; Performance\u003c\/h2\u003e\n\u003cp\u003eHot dip galvanizing (HDG) is the most robust zinc coating process available for carbon and alloy steel fasteners. The steel is immersed in a bath of molten zinc at approximately 450°C, forming a series of zinc-iron alloy layers topped by a pure zinc outer layer — metallurgically bonded to the steel substrate, not merely adhered.\u003c\/p\u003e\n\n\u003ch3\u003eHDG Process Steps\u003c\/h3\u003e\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDegreasing:\u003c\/strong\u003e Removal of oils, grease, and organic contaminants\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePickling:\u003c\/strong\u003e Acid cleaning to remove mill scale and rust — carefully controlled for Grade 8.8 to minimize hydrogen absorption\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFluxing:\u003c\/strong\u003e Application of zinc ammonium chloride flux to prevent oxidation before galvanizing\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGalvanizing:\u003c\/strong\u003e Immersion in molten zinc bath at ~450°C for controlled dwell time\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQuenching \u0026amp; Inspection:\u003c\/strong\u003e Cooling, visual inspection, and coating thickness verification per ISO 1461\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eHDG Coating Structure\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGamma layer (Γ):\u003c\/strong\u003e ~5 µm — zinc-iron alloy (innermost, highest iron content, hardest layer)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDelta layer (δ):\u003c\/strong\u003e ~20 µm — zinc-iron alloy (intermediate, columnar structure)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eZeta layer (ζ):\u003c\/strong\u003e ~15 µm — zinc-iron alloy (columnar crystals, visible spangle)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEta layer (η):\u003c\/strong\u003e ~10–20 µm — pure zinc (outermost, provides cathodic protection)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eKey Performance Advantages\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eProperty\u003c\/th\u003e\n      \u003cth\u003eHot Dip Galvanized (HDG)\u003c\/th\u003e\n      \u003cth\u003eZinc CR3 Electroplate\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCoating Thickness\u003c\/td\u003e\n      \u003ctd\u003e45 – 85 µm\u003c\/td\u003e\n      \u003ctd\u003e5 – 12 µm\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eBond Type\u003c\/td\u003e\n      \u003ctd\u003eMetallurgical (alloy bond)\u003c\/td\u003e\n      \u003ctd\u003eMechanical adhesion\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eSalt Spray Resistance\u003c\/td\u003e\n      \u003ctd\u003e≥ 1,000 hours\u003c\/td\u003e\n      \u003ctd\u003e72 – 120 hours (Grade 8.8)\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eOutdoor Service Life\u003c\/td\u003e\n      \u003ctd\u003e20 – 50+ years\u003c\/td\u003e\n      \u003ctd\u003e3 – 7 years (exposed)\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCathodic Protection\u003c\/td\u003e\n      \u003ctd\u003e✅ Yes — sacrificial zinc protects exposed steel\u003c\/td\u003e\n      \u003ctd\u003eLimited\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eSelf-Healing\u003c\/td\u003e\n      \u003ctd\u003e✅ Yes — zinc oxide\/carbonate forms at scratches\u003c\/td\u003e\n      \u003ctd\u003e❌ No\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eThread Fit\u003c\/td\u003e\n      \u003ctd\u003eRequires oversize tapping (HDG nuts)\u003c\/td\u003e\n      \u003ctd\u003eStandard thread fit\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eBest For\u003c\/td\u003e\n      \u003ctd\u003eOutdoor, structural, heavy-duty, long-term\u003c\/td\u003e\n      \u003ctd\u003eIndoor, light-to-medium duty, precision fit\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cblockquote\u003e\n  \u003cp\u003e\u003cstrong\u003e⚠️ Important — Hydrogen Embrittlement in Grade 8.8 HDG:\u003c\/strong\u003e The pickling step in the HDG process can introduce hydrogen into high-strength steel. For Grade 8.8 fasteners (hardness 250–320 HV), FULLERKREG applies controlled pickling parameters and, where required, a post-pickling baking process to minimize hydrogen absorption before galvanizing. All Grade 8.8 HDG bolts are inspected per EN ISO 10684 requirements.\u003c\/p\u003e\n\u003c\/blockquote\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eDimensional Reference — DIN 603 Key Parameters\u003c\/h2\u003e\n\u003cp\u003e\u003cem\u003eNote: Hot dip galvanizing adds 45–85 µm of coating per surface. Nuts must be tapped oversize (typically one tolerance class) to accommodate the coating thickness on threaded sections. Always specify HDG nuts when ordering.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eThread Size\u003c\/th\u003e\n      \u003cth\u003ePitch (mm)\u003c\/th\u003e\n      \u003cth\u003eHead Diameter dk (mm)\u003c\/th\u003e\n      \u003cth\u003eHead Height k (mm)\u003c\/th\u003e\n      \u003cth\u003eSquare Neck Width f (mm)\u003c\/th\u003e\n      \u003cth\u003eSquare Neck Height m (mm)\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM5\u003c\/td\u003e\n\u003ctd\u003e0.8\u003c\/td\u003e\n\u003ctd\u003e14.0\u003c\/td\u003e\n\u003ctd\u003e3.0\u003c\/td\u003e\n\u003ctd\u003e5.0\u003c\/td\u003e\n\u003ctd\u003e3.5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM6\u003c\/td\u003e\n\u003ctd\u003e1.0\u003c\/td\u003e\n\u003ctd\u003e16.0\u003c\/td\u003e\n\u003ctd\u003e3.6\u003c\/td\u003e\n\u003ctd\u003e6.0\u003c\/td\u003e\n\u003ctd\u003e4.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM8\u003c\/td\u003e\n\u003ctd\u003e1.25\u003c\/td\u003e\n\u003ctd\u003e21.0\u003c\/td\u003e\n\u003ctd\u003e4.8\u003c\/td\u003e\n\u003ctd\u003e8.0\u003c\/td\u003e\n\u003ctd\u003e5.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM10\u003c\/td\u003e\n\u003ctd\u003e1.5\u003c\/td\u003e\n\u003ctd\u003e26.0\u003c\/td\u003e\n\u003ctd\u003e6.0\u003c\/td\u003e\n\u003ctd\u003e10.0\u003c\/td\u003e\n\u003ctd\u003e6.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM12\u003c\/td\u003e\n\u003ctd\u003e1.75\u003c\/td\u003e\n\u003ctd\u003e30.0\u003c\/td\u003e\n\u003ctd\u003e7.2\u003c\/td\u003e\n\u003ctd\u003e12.0\u003c\/td\u003e\n\u003ctd\u003e7.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM14\u003c\/td\u003e\n\u003ctd\u003e2.0\u003c\/td\u003e\n\u003ctd\u003e35.0\u003c\/td\u003e\n\u003ctd\u003e8.4\u003c\/td\u003e\n\u003ctd\u003e14.0\u003c\/td\u003e\n\u003ctd\u003e8.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM16\u003c\/td\u003e\n\u003ctd\u003e2.0\u003c\/td\u003e\n\u003ctd\u003e40.0\u003c\/td\u003e\n\u003ctd\u003e9.6\u003c\/td\u003e\n\u003ctd\u003e16.0\u003c\/td\u003e\n\u003ctd\u003e9.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM20\u003c\/td\u003e\n\u003ctd\u003e2.5\u003c\/td\u003e\n\u003ctd\u003e50.0\u003c\/td\u003e\n\u003ctd\u003e12.0\u003c\/td\u003e\n\u003ctd\u003e20.0\u003c\/td\u003e\n\u003ctd\u003e11.0\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eStandard lengths range from 20 mm to 300 mm depending on thread size. Custom lengths available upon request.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eTypical Application Sectors\u003c\/h2\u003e\n\n\u003ch3\u003e🏗️ Heavy Structural Timber \u0026amp; Civil Engineering\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eHeavy timber frame and post-and-beam structural connections — permanent outdoor installations\u003c\/li\u003e\n  \u003cli\u003eGlulam beam, LVL, and CLT structural joints in exposed or semi-exposed conditions\u003c\/li\u003e\n  \u003cli\u003eTimber bridge decking, boardwalk, and pedestrian walkway structural fastening\u003c\/li\u003e\n  \u003cli\u003eRetaining wall timber crib and sleeper connections under high lateral load\u003c\/li\u003e\n  \u003cli\u003eUtility pole cross-arm and transmission tower timber connections\u003c\/li\u003e\n  \u003cli\u003eRailway sleeper and track infrastructure structural fastening\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e🌳 Outdoor \u0026amp; Landscape Structures (Heavy-Duty)\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eHeavy-duty decking, pergola, and outdoor pavilion structural connections\u003c\/li\u003e\n  \u003cli\u003eJetty, pontoon, and marine timber structure fastening (above waterline)\u003c\/li\u003e\n  \u003cli\u003eCoastal boardwalk and promenade structural timber connections\u003c\/li\u003e\n  \u003cli\u003eHeavy-duty playground and recreational equipment structural fastening\u003c\/li\u003e\n  \u003cli\u003eSports facility bleacher, grandstand, and spectator structure connections\u003c\/li\u003e\n  \u003cli\u003eOutdoor signage and large-format display structure mounting\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e🌾 Agricultural \u0026amp; Rural Infrastructure\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eFarm building and barn heavy structural connections\u003c\/li\u003e\n  \u003cli\u003eGrain store, silo, and agricultural storage structure fastening\u003c\/li\u003e\n  \u003cli\u003eLivestock pen, stable, and yard heavy fencing structural connections\u003c\/li\u003e\n  \u003cli\u003eIrrigation system support structure fastening\u003c\/li\u003e\n  \u003cli\u003eAgricultural machinery frame and implement structural connections\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e⚡ Industrial \u0026amp; Infrastructure\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eHighway noise barrier and crash barrier structural joints\u003c\/li\u003e\n  \u003cli\u003eWater treatment and wastewater facility structural fastening\u003c\/li\u003e\n  \u003cli\u003eMining and quarrying equipment structural connections\u003c\/li\u003e\n  \u003cli\u003eConveyor and material handling system heavy structural fastening\u003c\/li\u003e\n  \u003cli\u003eIndustrial storage rack and mezzanine floor structural connections\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eKey Features \u0026amp; Design Advantages\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e💪 \u003cstrong\u003eHigh-Strength Grade 8.8 + Maximum Corrosion Protection:\u003c\/strong\u003e The premium combination — Grade 8.8 tensile strength (≥ 800 MPa) paired with HDG zinc coating (45–85 µm) for decades of outdoor structural performance. Neither strength nor durability is compromised.\u003c\/li\u003e\n  \u003cli\u003e🔒 \u003cstrong\u003eAnti-Rotation Square Neck:\u003c\/strong\u003e The square collar embeds into timber or a pre-punched square hole, preventing bolt rotation during nut tightening — enabling single-sided assembly even in difficult access conditions.\u003c\/li\u003e\n  \u003cli\u003e❤️ \u003cstrong\u003eCathodic (Sacrificial) Protection:\u003c\/strong\u003e Even if the zinc coating is scratched or damaged, the surrounding zinc acts as a sacrificial anode, protecting the exposed steel from rusting — critical for permanent structural joints that cannot be easily inspected or maintained.\u003c\/li\u003e\n  \u003cli\u003e⚙️ \u003cstrong\u003eMetallurgical Bond:\u003c\/strong\u003e The HDG zinc-iron alloy layers are bonded at the atomic level — the coating cannot peel, flake, or delaminate under the high mechanical stresses generated by Grade 8.8 tightening torques.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eDual Material Options:\u003c\/strong\u003e Alloy Steel 10B21 (boron steel, preferred for OEM and high-volume structural supply) or Carbon Steel 35K (cost-effective for general structural applications).\u003c\/li\u003e\n  \u003cli\u003e📏 \u003cstrong\u003eLong Service Life:\u003c\/strong\u003e In rural atmospheric conditions, HDG Grade 8.8 fasteners typically provide 50+ years of maintenance-free structural service. In urban or industrial environments, 20–30 years is typical.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eInstallation Notes for Grade 8.8 HDG Carriage Bolts\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNut and washer selection:\u003c\/strong\u003e Always use HDG nuts (tapped oversize) and HDG hardened washers with Grade 8.8 HDG bolts. Standard-tolerance nuts will not fit due to the additional coating thickness. Hardened washers (Grade 8 equivalent) are required under the nut to distribute the high clamping load.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eVerify substrate capacity:\u003c\/strong\u003e Grade 8.8 generates significantly higher clamping forces than Grade 4.8. Confirm that the timber species, metal thickness, or composite substrate is rated for the increased bearing stress at the bolt head and nut contact areas.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHole preparation:\u003c\/strong\u003e Drill clearance holes to the nominal bolt diameter. The HDG coating on the shank adds minimal bulk — standard clearance holes are generally acceptable.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSquare neck embedding:\u003c\/strong\u003e Insert the bolt from the front face and tap firmly with a mallet to seat the square neck. Grade 8.8 bolts require firm seating to prevent rotation under higher tightening torques.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTightening:\u003c\/strong\u003e Use a calibrated torque wrench. Tighten from the nut side only. Do not exceed the maximum recommended torque — Grade 8.8 fasteners are susceptible to torsional fracture if overtightened.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGalvanic compatibility:\u003c\/strong\u003e When fastening aluminium or copper components, use isolation washers or sleeves to prevent galvanic corrosion between dissimilar metals.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePeriodic inspection:\u003c\/strong\u003e For permanent structural applications, inspect fastener condition and torque retention at regular intervals per the applicable structural design standard.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eRecommended Tightening Torque — Grade 8.8\u003c\/h2\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eThread Size\u003c\/th\u003e\n      \u003cth\u003eTightening Torque (Nm) — Dry\u003c\/th\u003e\n      \u003cth\u003eTightening Torque (Nm) — Lubricated\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM5\u003c\/td\u003e\n\u003ctd\u003e6.0\u003c\/td\u003e\n\u003ctd\u003e4.5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM6\u003c\/td\u003e\n\u003ctd\u003e10.4\u003c\/td\u003e\n\u003ctd\u003e7.8\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM8\u003c\/td\u003e\n\u003ctd\u003e25\u003c\/td\u003e\n\u003ctd\u003e19\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM10\u003c\/td\u003e\n\u003ctd\u003e50\u003c\/td\u003e\n\u003ctd\u003e38\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM12\u003c\/td\u003e\n\u003ctd\u003e87\u003c\/td\u003e\n\u003ctd\u003e65\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM14\u003c\/td\u003e\n\u003ctd\u003e138\u003c\/td\u003e\n\u003ctd\u003e104\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM16\u003c\/td\u003e\n\u003ctd\u003e213\u003c\/td\u003e\n\u003ctd\u003e160\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM20\u003c\/td\u003e\n\u003ctd\u003e415\u003c\/td\u003e\n\u003ctd\u003e311\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eTorque values are indicative for Grade 8.8 bolts at 70% proof load. Use a calibrated torque wrench for all structural applications. Always verify with your structural engineer for safety-critical joints.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eWhy Choose FULLERKREG DIN 603 Grade 8.8 Hot Dip Galvanized?\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eFull DIN 603, ISO 898-1 \u0026amp; ISO 1461 Compliance:\u003c\/strong\u003e Every batch manufactured to DIN 603 dimensional standards, Grade 8.8 mechanical requirements, and ISO 1461 hot dip galvanizing specifications.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003ePremium Strength + Durability Combination:\u003c\/strong\u003e Grade 8.8 mechanical performance combined with HDG long-term corrosion protection — the definitive specification for permanent outdoor structural fastening.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eHydrogen Embrittlement Controlled:\u003c\/strong\u003e Controlled pickling parameters and process management per EN ISO 10684 to minimize hydrogen absorption during the HDG process for Grade 8.8 fasteners.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eDual Material Options:\u003c\/strong\u003e Alloy Steel 10B21 or Carbon Steel 35K — both meeting Grade 8.8 requirements.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eFull Traceability:\u003c\/strong\u003e Material certificates (MTC), mechanical test reports, hardness records, and ISO 1461 coating thickness inspection records available per shipment.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eWide Size Range:\u003c\/strong\u003e M5 through M20, lengths from 20 mm to 300 mm.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eMatched HDG Nuts \u0026amp; Hardened Washers Available:\u003c\/strong\u003e Complete HDG Grade 8.8 fastener sets (bolt + nut + washer) available for simplified procurement.\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eFlexible Packaging:\u003c\/strong\u003e Bulk, box, and pallet options available to suit construction site and project requirements.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eApplicable Standards \u0026amp; References\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDIN 603\u003c\/strong\u003e — Round head square neck bolts (metric coarse thread)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDIN EN ISO 898-1\u003c\/strong\u003e — Mechanical properties of fasteners: bolts, screws and studs (property class 8.8)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eISO 1461\u003c\/strong\u003e — Hot dip galvanized coatings on fabricated iron and steel articles — specifications and test methods\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEN ISO 10684\u003c\/strong\u003e — Fasteners — hot dip galvanized coatings\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eISO 9227\u003c\/strong\u003e — Corrosion tests in artificial atmospheres — neutral salt spray (NSS) test\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGB\/T 700 \/ GB\/T 3077\u003c\/strong\u003e — Carbon and alloy structural steels (35K and 10B21 material standards)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eOrdering \u0026amp; Customization\u003c\/h2\u003e\n\u003cp\u003eFULLERKREG supplies DIN 603 Grade 8.8 Hot Dip Galvanized carriage bolts in standard and custom configurations. Please specify the following when placing an inquiry:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eThread diameter and pitch (e.g., M10 × 1.5, M12 × 1.75)\u003c\/li\u003e\n  \u003cli\u003eNominal length (e.g., 50 mm, 100 mm, 200 mm)\u003c\/li\u003e\n  \u003cli\u003eFully threaded or partially threaded shank preference\u003c\/li\u003e\n  \u003cli\u003eMaterial preference: Alloy Steel 10B21 or Carbon Steel 35K\u003c\/li\u003e\n  \u003cli\u003eWhether matched HDG nuts and hardened washers are required\u003c\/li\u003e\n  \u003cli\u003eRequired quantity and packaging format (bulk \/ box \/ pallet)\u003c\/li\u003e\n  \u003cli\u003eCertification requirements (ISO 1461 coating reports, material certificates, mechanical test reports, hardness records)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eContact our technical sales team for datasheets, samples, and volume pricing.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\u003cem\u003eFULLERKREG — High-Strength Fasteners Built for the Long Term. Grade 8.8 Strength. Hot Dip Galvanized Durability.\u003c\/em\u003e\u003c\/p\u003e","products":[],"url":"https:\/\/www.fullerkr.com\/collections\/din-603-carriage-bolt-8-8-hot-dip-galvanized.oembed","provider":"Fullerkreg Fasteners","version":"1.0","type":"link"}