Lesson 1Common structural steels for doors: S235, S275, mild steel properties and selection criteriaIntroduces common structural steels for doors, such as S235, S275, and mild steel grades. Discusses yield strength, weldability, toughness, coating behavior, and how to select grades for frames, leaves, and reinforcing plates.
Mechanical properties of S235 and S275Mild steel chemistry and weldabilityFormability for bends, hems, and profilesCoating performance and galvanizing issuesSelecting grades for frames and stiffenersLesson 2Deadbolt types and dimensions: single-throw vs double-throw, bolt materials and typical diametersExplores deadbolt designs for steel doors, comparing single-throw and double-throw mechanisms. Reviews bolt materials, diameters, throw length, latch guards, and how to coordinate with cylinders, strikes, and security standards.
Single-throw vs double-throw mechanismsBolt materials, hardness, and corrosionBolt diameter, throw length, and clearancesStrike plates, boxes, and reinforcementCompatibility with cylinders and escutcheonsLesson 3Sheet thickness selection for door leafs and frames: 1.5–6 mm ranges, tradeoffs between weight and securityGuides selection of sheet thickness for door leaves and frames from 1.5–6 mm. Discusses stiffness, dent resistance, weight, hinge loading, and security performance, including typical gauges for industrial, fire, and high-security 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 4Standard cylinder lock types for metal doors: euro-profile, rim cylinder, tubular, mortise cylinders—dimensions and backsetCovers main cylinder formats used in metal doors, including euro-profile, rim, tubular, and mortise cylinders. Explains dimensional standards, backset, cam types, keying options, and compatibility with multipoint and panic hardware.
Euro-profile cylinder dimensions and camsRim cylinders for surface-mounted locksTubular cylinders and keyway optionsMortise cylinders and thread standardsBackset, center distance, and door prepLesson 5Materials selection checklist for warehouse entrance doors (weight, security rating, cost)Provides a practical checklist for choosing materials for warehouse entrance doors. Balances weight, security rating, corrosion resistance, fire and egress needs, hardware compatibility, and total installed and lifecycle cost.
Door leaf gauge, profiles, and reinforcementsFrame type, anchors, and substrate checksLocking, cylinders, and access controlCorrosion protection and environment classBudget, lifecycle cost, and maintenanceLesson 6Standard steel profiles: rectangular tube, square tube, angle irons, flat bars—dimensions, wall thicknesses, and use casesDetails common hollow and solid steel profiles used in door frames, stiffeners, and reinforcing. Reviews dimensional series, wall thickness ranges, tolerances, and how profile choice affects strength, weight, and fabrication 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 7Fasteners and anchors to concrete: mechanical anchors, chemical anchors, anchor sizing and embedment depthsDescribes mechanical and chemical anchors for fixing steel frames to concrete. Covers base material assessment, anchor sizing, embedment depth, edge distances, load paths, and installation practices to avoid loosening or cracking.
Concrete strength, cracking, and inspectionExpansion anchors and sleeve anchorsAdhesive anchors and curing conditionsEmbedment depth, spacing, and edge distanceTorque, installation, and pull-out testingLesson 8Hinges and pivot hardware for high-use doors: butt hinges, continuous hinges, pin types, security hinge optionsExamines hinge and pivot options for high-use steel doors. Compares butt and continuous hinges, pivot sets, pin and bearing types, security features, and sizing based on door weight, frequency of use, and fire or escape requirements.
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 9Corrosion protection options: galvanizing, paint systems, powder coat, surface prep standardsExplains corrosion mechanisms on steel doors, then compares galvanizing, liquid paint, and powder coating. Covers surface preparation standards, film thickness, inspection, and how to match protection systems to environment and service life.
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 SSPC
