- Galvannealed 20 / 18 / 16 gauge faces
- Polystyrene or polyurethane core
- Labelled 20 min – 3 h fire ratings
- 7 ga hinge, 12 ga closer reinforcement
- Non-handed leaf, square seamed edges
- Knock-down or welded 16 / 14 ga frames
What it is
A hollow metal door is two steel face sheets bonded to an insulating core, closed with welded steel channels and reinforced for hinges, locks and closers. It hangs in a pressed steel frame anchored to the wall – the standard opening for factories, warehouses, schools, hospitals, offices and apartment buildings.
World Steel supplies the complete opening: door, frame, anchors and the hardware set, prepared and reinforced to the same schedule so it installs without site cutting. Doors and frames ship with the steel building or as a stand-alone package.
Why galvannealed steel
Galvannealed sheet is zinc-coated steel annealed at a higher temperature, so the zinc and iron combine into a zinc-iron alloy layer. It is harder than ordinary galvanizing, welds cleanly and has a matte surface that takes paint far better – the reason it is the standard for commercial doors.
- A40 coating (A60 for coastal or high-humidity sites)
- Cleaned inside and out before priming
- Baked-on rust-inhibitive primer, ready for the final colour
Construction
| Element | WS standard |
|---|---|
| Faces | 18 or 20 gauge galvannealed (16 gauge for extra-heavy duty) |
| Thickness | 1¾ in (45 mm) |
| Core | Polystyrene 1.0 lb/ft³ – R 7.1, U 0.14 · polyurethane 2.0 lb/ft³ – R 11.0, U 0.091 · steel-stiffened |
| Edges | Square vertical edges with mechanical interlocking seam, no face seams |
| Top & bottom | 16 gauge inverted channels, steel top cap installed |
| Hinge reinforcement | 7 gauge (3/16 in), universal 4½ in prep for standard or heavy-weight hinges |
| Lock | Reinforced 161 cylindrical prep; 86 mortise, exit device and deadbolt preps |
| Closer | 12 gauge reinforcement both sides |
| Max. size | Single 4'0" × 8'0" · pair 8'0" × 8'0" |
Duty levels
| Face sheet | Duty level | Typical use | Frame |
|---|---|---|---|
| 16 gauge | Extra-heavy duty | Plant rooms, stairs, high-traffic exterior | 16 or 14 gauge |
| 18 gauge | Heavy duty | Exterior and corridor doors, factories | 16 gauge |
| 20 gauge | Standard duty | Offices, apartments, interior rooms | 16 gauge |
Wind-rated assemblies for hurricane regions and doors with glass lites, louvres, astragals and electrified hardware preparations are available on request.
Fire-rated openings
Labelled doors and frames are available from 20 minutes to 3 hours, tested to positive-pressure fire standards. The label applies to the assembly – door, frame, hinges, latching hardware and closer – so we supply rated openings as complete sets with the matching listed hardware.
A fire door is only as good as its installation: frames anchored to the wall type, clearances within limits and self-closing, positive-latching hardware.
各市场标准与要求
World Steel 设计、加工本产品及编制文件所依据的规范——以及各市场的主要几何与荷载要求。
美国
- ANSI/SDI A250.8Standard steel doors and frames (SDI-100)
- ANSI/SDI A250.6Hardware reinforcings on steel doors and frames
- ANSI/DHI A115 seriesHardware preparation in steel doors and frames
- ASTM A653 / A924Galvannealed steel sheet A40 / A60
- NFPA 80 · UL 10CFire doors – installation and positive-pressure fire test
- Fire label
- 20 min to 3 h on a labelled door and frame
- Accessibility
- ADA / ICC A117.1 – threshold rise ≤ ½ in
澳大利亚 / 新西兰
- AS 1905.1Fire-resistant doorsets
- AS 1530.4Fire-resistance tests of elements
- NCC Volume OneEgress, fire separation and access
- AS 1428.1Design for access – door circulation and hardware
- Fire doorset
- door, frame and hardware tested as one assembly
欧洲
- EN 14351-1Windows and external pedestrian doorsets – CE marking
- EN 16034Fire and smoke resisting doorsets – CE marking
- EN 1634-1Fire resistance test for doorsets
- EN 1192Doors – classification of strength requirements
- CE marking
- Declaration of performance for each doorset type
摘要仅供参考——以项目技术规格书、所采用的规范版本及主管机构要求为准。
表面处理
| 表面处理 | 标准 / 备注 |
|---|---|
| Prime coat | Baked-on rust-inhibitive primer to ANSI A250.10 – primer gray standard |
| Factory colours | Light gray, bronze, true white, bright white, off white |
| Field finish | Primer accepts alkyd, acrylic or polyurethane topcoats |
常见问题
What is the difference between galvanized and galvannealed doors?
Galvannealed steel is annealed after coating so the zinc alloys with the iron. The surface is harder, welds cleanly and holds paint better, which is why it is the standard for commercial hollow metal doors.
Which gauge do I need?
18 gauge suits most exterior and corridor doors; 16 gauge is for heavy-traffic and abuse-prone openings; 20 gauge is fine for interior rooms with moderate use.
Are the doors handed?
The leaves are non-handed with square edges, so one door fits a left or right hand opening. Frames are prepared for the hand you order.









