{"title":"GB\/T 9074.13-1988 Cross Recessed Hexagon Bolt with Indentation, Single Coil Lock Washer and Plain Washer Assemblies - Marine Stainless Steel A4","description":"\u003ch1\u003eGB\/T 9074.13-1988 Cross Recessed Hexagon Bolt with Indentation, Single Coil Lock Washer and Plain Washer Assemblies — Marine Stainless Steel A4\u003c\/h1\u003e\n\n\u003cp\u003eFULLERKREG supplies GB\/T 9074.13-1988 marine-grade A4 (SUS316) SEMS screws — pre-assembled three-piece fastener assemblies combining a cross recessed hexagon bolt, a single coil spring lock washer, and a plain washer into one captive unit. Engineered for demanding environments where superior corrosion resistance is essential: marine, offshore, chemical processing, food-grade, and outdoor infrastructure applications.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eWhat Are GB9074.13 Cross Recessed Hex SEMS Screws?\u003c\/h2\u003e\n\n\u003cp\u003eGB\/T 9074.13-1988 defines a three-piece pre-assembled fastener (SEMS) consisting of:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGB29.2\u003c\/strong\u003e — Cross recessed hexagon head bolt (Phillips drive, hex head)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGB9074.24\u003c\/strong\u003e — Plain washer (assembly-grade flat washer)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGB9074.26\u003c\/strong\u003e — Single coil spring lock washer (assembly-grade spring washer)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThe three components are permanently captivated onto the bolt shank before thread rolling. After threading, the outer thread diameter exceeds the inner diameter of the plain washer, making the assembly permanently inseparable. This eliminates loose washers on the assembly line and dramatically reduces installation time and error.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAssembly formula:\u003c\/strong\u003e GB9074.13 = GB29.2 + GB9074.24 + GB9074.26\u003c\/p\u003e\n\n\u003cp\u003eThe washer stack order from bolt head outward is: \u003cstrong\u003ePlain Washer → Spring Lock Washer → Bolt Head\u003c\/strong\u003e (the plain washer sits closest to the workpiece surface).\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eBenefits of Using GB9074.13 Cross Recessed Hex SEMS Screws\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eNo loose parts\u003c\/strong\u003e — washers are permanently captivated; no risk of dropped or missing washers during assembly\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eFaster installation\u003c\/strong\u003e — one-piece handling replaces three separate components; ideal for automated and manual assembly lines\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eCorrect washer sequence guaranteed\u003c\/strong\u003e — plain washer always contacts the workpiece; spring washer always contacts the bolt head flange\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eVibration resistance\u003c\/strong\u003e — the coil spring lock washer provides reliable anti-loosening performance under dynamic and cyclic loads\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eDual drive flexibility\u003c\/strong\u003e — cross recessed (Phillips) drive on a hex head allows both manual screwdriver and power tool \/ wrench tightening\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eSuperior marine-grade corrosion resistance\u003c\/strong\u003e — A4 (SUS316) stainless steel with 2–3% molybdenum content delivers outstanding resistance to chloride-induced pitting and crevice corrosion in salt-spray and seawater environments\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eFood \u0026amp; chemical process compatible\u003c\/strong\u003e — SUS316 is widely accepted for food processing equipment and chemical plant hardware\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eReduced inventory complexity\u003c\/strong\u003e — one SKU replaces three separate fastener SKUs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eMaterial \u0026amp; Finish\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    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMaterial\u003c\/td\u003e\n      \u003ctd\u003eA4 Marine Stainless Steel (SUS316 \/ 316 SS)\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eKey Alloying Element\u003c\/td\u003e\n      \u003ctd\u003eMolybdenum (Mo) 2.0–3.0% — enhances chloride \u0026amp; pitting resistance\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eSurface Finish\u003c\/td\u003e\n      \u003ctd\u003eNatural (Bright Passivated)\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eProperty Class\u003c\/td\u003e\n      \u003ctd\u003eA4-70\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eTensile Strength\u003c\/td\u003e\n      \u003ctd\u003e≥ 700 MPa\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYield Strength (0.2% proof)\u003c\/td\u003e\n      \u003ctd\u003e≥ 450 MPa\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCorrosion Resistance\u003c\/td\u003e\n      \u003ctd\u003eExcellent — superior to A2 in chloride, salt-spray, and marine environments\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMagnetic\u003c\/td\u003e\n      \u003ctd\u003eSlightly magnetic (work-hardened 316)\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eRoHS Compliant\u003c\/td\u003e\n      \u003ctd\u003eYes\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eA4 vs A2 — Why Choose Marine Grade?\u003c\/h3\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eProperty\u003c\/th\u003e\n      \u003cth\u003eA2 (SUS304)\u003c\/th\u003e\n      \u003cth\u003eA4 (SUS316)\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMolybdenum Content\u003c\/td\u003e\n      \u003ctd\u003eNone\u003c\/td\u003e\n      \u003ctd\u003e2.0–3.0%\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eChloride Resistance\u003c\/td\u003e\n      \u003ctd\u003eModerate\u003c\/td\u003e\n      \u003ctd\u003eSuperior\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMarine \/ Salt-spray\u003c\/td\u003e\n      \u003ctd\u003eLimited\u003c\/td\u003e\n      \u003ctd\u003eRecommended\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eFood \u0026amp; Chemical Use\u003c\/td\u003e\n      \u003ctd\u003eGeneral\u003c\/td\u003e\n      \u003ctd\u003ePreferred\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCost\u003c\/td\u003e\n      \u003ctd\u003eStandard\u003c\/td\u003e\n      \u003ctd\u003ePremium\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eDimensions of Pre-Assembled Washers in GB9074.13 Hex Head SEMS Screws\u003c\/h2\u003e\n\n\u003cp\u003eWasher dimensions conform to \u003cstrong\u003eGB9074.24\u003c\/strong\u003e (plain washer) and \u003cstrong\u003eGB9074.26\u003c\/strong\u003e (spring lock washer). All dimensions in millimeters (mm).\u003c\/p\u003e\n\n\u003ch3\u003ePlain Washer Dimensions (GB9074.24)\u003c\/h3\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eThread Size\u003c\/th\u003e\n      \u003cth\u003eInner Dia. d₁ (mm)\u003c\/th\u003e\n      \u003cth\u003eOuter Dia. d₂ (mm)\u003c\/th\u003e\n      \u003cth\u003eThickness h (mm)\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM4\u003c\/td\u003e\n\u003ctd\u003e4.3\u003c\/td\u003e\n\u003ctd\u003e9.0\u003c\/td\u003e\n\u003ctd\u003e0.8\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM5\u003c\/td\u003e\n\u003ctd\u003e5.3\u003c\/td\u003e\n\u003ctd\u003e10.0\u003c\/td\u003e\n\u003ctd\u003e1.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM6\u003c\/td\u003e\n\u003ctd\u003e6.4\u003c\/td\u003e\n\u003ctd\u003e12.0\u003c\/td\u003e\n\u003ctd\u003e1.6\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM8\u003c\/td\u003e\n\u003ctd\u003e8.4\u003c\/td\u003e\n\u003ctd\u003e16.0\u003c\/td\u003e\n\u003ctd\u003e1.6\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM10\u003c\/td\u003e\n\u003ctd\u003e10.5\u003c\/td\u003e\n\u003ctd\u003e20.0\u003c\/td\u003e\n\u003ctd\u003e2.0\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eSpring Lock Washer Dimensions (GB9074.26)\u003c\/h3\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eThread Size\u003c\/th\u003e\n      \u003cth\u003eInner Dia. d₁ (mm)\u003c\/th\u003e\n      \u003cth\u003eOuter Dia. d₂ (mm)\u003c\/th\u003e\n      \u003cth\u003eThickness s (mm)\u003c\/th\u003e\n      \u003cth\u003eWidth b (mm)\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM4\u003c\/td\u003e\n\u003ctd\u003e4.1\u003c\/td\u003e\n\u003ctd\u003e7.1\u003c\/td\u003e\n\u003ctd\u003e0.9\u003c\/td\u003e\n\u003ctd\u003e1.5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM5\u003c\/td\u003e\n\u003ctd\u003e5.1\u003c\/td\u003e\n\u003ctd\u003e8.7\u003c\/td\u003e\n\u003ctd\u003e1.2\u003c\/td\u003e\n\u003ctd\u003e1.8\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM6\u003c\/td\u003e\n\u003ctd\u003e6.1\u003c\/td\u003e\n\u003ctd\u003e10.2\u003c\/td\u003e\n\u003ctd\u003e1.6\u003c\/td\u003e\n\u003ctd\u003e2.0\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM8\u003c\/td\u003e\n\u003ctd\u003e8.1\u003c\/td\u003e\n\u003ctd\u003e13.0\u003c\/td\u003e\n\u003ctd\u003e2.0\u003c\/td\u003e\n\u003ctd\u003e2.5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM10\u003c\/td\u003e\n\u003ctd\u003e10.2\u003c\/td\u003e\n\u003ctd\u003e16.2\u003c\/td\u003e\n\u003ctd\u003e2.5\u003c\/td\u003e\n\u003ctd\u003e3.0\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eDimensional Data — GB9074.13 SEMS Screw (A4 Marine Stainless Steel)\u003c\/h2\u003e\n\n\u003cp\u003eAll dimensions in millimeters (mm). Bolt head dimensions per GB29.2. Nominal lengths per standard series.\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 Width Across Flats s (mm)\u003c\/th\u003e\n      \u003cth\u003eHead Width Across Corners e (mm)\u003c\/th\u003e\n      \u003cth\u003eHead Height k (mm)\u003c\/th\u003e\n      \u003cth\u003eCross Recess Depth (mm)\u003c\/th\u003e\n      \u003cth\u003eMin. Grip Length (mm)\u003c\/th\u003e\n      \u003cth\u003eNominal Length Range L (mm)\u003c\/th\u003e\n      \u003cth\u003eEst. Unit Weight (g\/pc) — M×16\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM4\u003c\/td\u003e\n\u003ctd\u003e0.7\u003c\/td\u003e\n\u003ctd\u003e7\u003c\/td\u003e\n\u003ctd\u003e7.66\u003c\/td\u003e\n\u003ctd\u003e2.8\u003c\/td\u003e\n\u003ctd\u003e1.8\u003c\/td\u003e\n\u003ctd\u003e10\u003c\/td\u003e\n\u003ctd\u003e10–40\u003c\/td\u003e\n\u003ctd\u003e≈ 1.5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM5\u003c\/td\u003e\n\u003ctd\u003e0.8\u003c\/td\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003ctd\u003e8.79\u003c\/td\u003e\n\u003ctd\u003e3.5\u003c\/td\u003e\n\u003ctd\u003e2.1\u003c\/td\u003e\n\u003ctd\u003e12\u003c\/td\u003e\n\u003ctd\u003e10–50\u003c\/td\u003e\n\u003ctd\u003e≈ 2.8\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\u003e10\u003c\/td\u003e\n\u003ctd\u003e11.05\u003c\/td\u003e\n\u003ctd\u003e4.0\u003c\/td\u003e\n\u003ctd\u003e2.4\u003c\/td\u003e\n\u003ctd\u003e14\u003c\/td\u003e\n\u003ctd\u003e12–60\u003c\/td\u003e\n\u003ctd\u003e≈ 4.8\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\u003e13\u003c\/td\u003e\n\u003ctd\u003e14.38\u003c\/td\u003e\n\u003ctd\u003e5.3\u003c\/td\u003e\n\u003ctd\u003e3.0\u003c\/td\u003e\n\u003ctd\u003e18\u003c\/td\u003e\n\u003ctd\u003e16–80\u003c\/td\u003e\n\u003ctd\u003e≈ 10.5\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\u003e16\u003c\/td\u003e\n\u003ctd\u003e17.77\u003c\/td\u003e\n\u003ctd\u003e6.4\u003c\/td\u003e\n\u003ctd\u003e3.6\u003c\/td\u003e\n\u003ctd\u003e22\u003c\/td\u003e\n\u003ctd\u003e20–100\u003c\/td\u003e\n\u003ctd\u003e≈ 19.0\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cp\u003e\u003cem\u003eNote: Unit weights are approximate reference values for L=16mm. Actual weight varies with nominal length. Contact FULLERKREG for precise weight data for your specific length requirement.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eProduct Gallery\u003c\/h2\u003e\n\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"width:25%; text-align:center; padding:8px;\"\u003e \u003c\/td\u003e\n      \u003ctd style=\"width:25%; text-align:center; padding:8px;\"\u003e \u003c\/td\u003e\n      \u003ctd style=\"width:25%; text-align:center; padding:8px;\"\u003e \u003c\/td\u003e\n      \u003ctd style=\"width:25%; text-align:center; padding:8px;\"\u003e \u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eApplications\u003c\/h2\u003e\n\n\u003cp\u003eGB9074.13 A4 marine stainless steel SEMS screws are the preferred choice wherever chloride exposure, salt spray, or chemical contact demands superior corrosion resistance:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e⚓ \u003cstrong\u003eMarine \u0026amp; offshore structures\u003c\/strong\u003e — boat fittings, deck hardware, dock equipment, offshore platform enclosures\u003c\/li\u003e\n  \u003cli\u003e🌊 \u003cstrong\u003eCoastal \u0026amp; outdoor infrastructure\u003c\/strong\u003e — street furniture, signage, railing systems, bridge components in salt-air environments\u003c\/li\u003e\n  \u003cli\u003e🏭 \u003cstrong\u003eChemical \u0026amp; petrochemical processing\u003c\/strong\u003e — equipment panels, pipe flanges, instrument enclosures exposed to corrosive media\u003c\/li\u003e\n  \u003cli\u003e🍽️ \u003cstrong\u003eFood \u0026amp; beverage processing\u003c\/strong\u003e — SUS316 meets hygiene requirements for food-contact equipment and clean-room environments\u003c\/li\u003e\n  \u003cli\u003e⚡ \u003cstrong\u003eElectrical enclosures in harsh environments\u003c\/strong\u003e — outdoor switchgear, waterproof junction boxes, marine control panels\u003c\/li\u003e\n  \u003cli\u003e🔬 \u003cstrong\u003ePharmaceutical \u0026amp; medical equipment\u003c\/strong\u003e — where non-reactive, cleanable fasteners are required\u003c\/li\u003e\n  \u003cli\u003e🔧 \u003cstrong\u003eGeneral mechanical assembly\u003c\/strong\u003e — wherever pre-assembled washers eliminate loose-part handling on production lines in corrosive environments\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eWhy Choose FULLERKREG GB9074.13 A4 SEMS Screws?\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e🏭 \u003cstrong\u003eDirect manufacturer\u003c\/strong\u003e — produced in-house to GB\/T 9074.13-1988 standard with full dimensional traceability\u003c\/li\u003e\n  \u003cli\u003e📦 \u003cstrong\u003eBulk wholesale supply\u003c\/strong\u003e — flexible MOQ, competitive pricing for OEM and MRO procurement\u003c\/li\u003e\n  \u003cli\u003e📐 \u003cstrong\u003eStrict dimensional control\u003c\/strong\u003e — 100% thread gauge inspection; washer captivation verified per standard\u003c\/li\u003e\n  \u003cli\u003e📋 \u003cstrong\u003eMaterial certification available\u003c\/strong\u003e — mill test reports, SUS316 material certificates, and RoHS compliance documentation on request\u003c\/li\u003e\n  \u003cli\u003e🚀 \u003cstrong\u003eFast lead times\u003c\/strong\u003e — standard sizes held in stock; custom lengths available with short lead times\u003c\/li\u003e\n  \u003cli\u003e🌍 \u003cstrong\u003eGlobal export experience\u003c\/strong\u003e — export packaging, ISPM-15 compliant crating, and international logistics support\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\u003cstrong\u003eStandard:\u003c\/strong\u003e GB\/T 9074.13-1988 | \u003cstrong\u003eMaterial:\u003c\/strong\u003e A4 Marine Stainless Steel (SUS316) | \u003cstrong\u003eFinish:\u003c\/strong\u003e Bright Passivated | \u003cstrong\u003eProperty Class:\u003c\/strong\u003e A4-70 | \u003cstrong\u003eBrand:\u003c\/strong\u003e FULLERKREG\u003c\/p\u003e","products":[],"url":"https:\/\/www.fullerkr.com\/collections\/gb9074-13-a4.oembed","provider":"Fullerkreg Fasteners","version":"1.0","type":"link"}