Lesson 1Deadbolt types and dimensions: single-throw vs double-throw, bolt materials and typical diametersLooks at deadbolt designs for steel doors, comparing single-throw and double-throw types. Checks bolt materials, sizes, throw distance, guards, and how they fit with locks, strikes, and safety rules.
Single-throw vs double-throw mechanismsBolt materials, hardness, and corrosionBolt diameter, throw length, and clearancesStrike plates, boxes, and reinforcementCompatibility with cylinders and escutcheonsLesson 2Corrosion protection options: galvanizing, paint systems, powder coat, surface prep standardsShows how rust attacks steel doors, then compares dipping in zinc, wet paint, and powder coat. Covers cleaning standards, coat thickness, checks, and picking protection for weather and long use.
Atmospheric corrosion and exposure categoriesHot-dip galvanizing vs electro-galvanizingLiquid paint systems and zinc-rich primersPowder coating process and curing controlSurface prep grades per ISO and SSPCLesson 3Hinges and pivot hardware for high-use doors: butt hinges, continuous hinges, pin types, security hinge optionsChecks hinge and pivot choices for busy steel doors. Compares short and full hinges, pivot sets, pin types, bearings, safety bits, and sizes for door weight, daily use, and fire escape needs.
Butt hinge types, knuckle count, and sizingContinuous hinges for high-cycle applicationsFloor and top pivots for heavy doorsSecurity hinges, studs, and non-removable pinsBearing types, lubrication, and maintenanceLesson 4Fasteners and anchors to concrete: mechanical anchors, chemical anchors, anchor sizing and embedment depthsExplains bolt and glue anchors for fixing steel frames in concrete. Looks at base checks, sizes, depths, edge space, load paths, and ways to fit without pulling loose or cracking stone.
Concrete strength, cracking, and inspectionExpansion anchors and sleeve anchorsAdhesive anchors and curing conditionsEmbedment depth, spacing, and edge distanceTorque, installation, and pull-out testingLesson 5Standard steel profiles: rectangular tube, square tube, angle irons, flat bars—dimensions, wall thicknesses, and use casesLists common hollow and flat steel shapes for door frames, braces, and strength bits. Checks sizes, wall thicks, fits, and how choice affects power, weight, and workshop making effort.
Rectangular and square hollow section rangesAngle irons for frames and edge stiffenersFlat bars for strike, hinge, and lock platesWall thickness vs load and weld distortionSpecifying tolerances and mill certificatesLesson 6Materials selection checklist for warehouse entrance doors (weight, security rating, cost)Gives a simple list to pick materials for warehouse doors. Weighs weight, safety level, rust fight, fire escape, fittings match, and full cost from fit to long use.
Door leaf gauge, profiles, and reinforcementsFrame type, anchors, and substrate checksLocking, cylinders, and access controlCorrosion protection and environment classBudget, lifecycle cost, and maintenanceLesson 7Standard cylinder lock types for metal doors: euro-profile, rim cylinder, tubular, mortise cylinders—dimensions and backsetCovers main lock tube types for metal doors like euro, rim, tube, and built-in. Explains sizes, set-back, cam shapes, key ways, and fit with multi-lock and panic gear.
Euro-profile cylinder dimensions and camsRim cylinders for surface-mounted locksTubular cylinders and keyway optionsMortise cylinders and thread standardsBackset, center distance, and door prepLesson 8Sheet thickness selection for door leafs and frames: 1.5–6 mm ranges, tradeoffs between weight and securityGuides picking sheet thicks for doors and frames from 1.5 to 6 mm. Talks stiff, dent fight, weight, hinge load, safety, with common thicks for factory, fire, high-safe doors.
Typical gauge ranges for leaves and framesDeflection, dent resistance, and span limitsWeight impact on hinges and closersSecurity, burglary, and fire rating needsCost and fabrication implications by gaugeLesson 9Common structural steels for doors: S235, S275, mild steel properties and selection criteriaShows common steels for doors like S235, S275, soft steel. Talks bend strength, weld ease, tough, coat hold, and picking for frames, doors, brace plates.
Mechanical properties of S235 and S275Mild steel chemistry and weldabilityFormability for bends, hems, and profilesCoating performance and galvanizing issuesSelecting grades for frames and stiffeners
