Pendahuluan
RFQ yang menulis GI coil, 0.45 x 1000, Z80 or Z140 OK tidak membekukan coating. Satu pabrik menawar EN 10346 Z140. Yang lain mengisi Z80 pada FOB yang sama dan menulis “equivalent zinc”. Yang ketiga mencetak G90 di proforma dan Z140 di EN 10204 3.1 MTC. Tebal bisa cocok. Spangle bisa cocok. Seng pada strip tidak.
Baris coating yang membuat tiga penawaran tidak bisa dibandingkan
Ringkasan teknis cepat (jawaban langsung): Z80, Z140, dan Z275 menamai massa seng minimum, total kedua sisi, bukan mikron pada PO dan bukan stok 100% setara. Bekukan standar (EN 10346, ASTM A653, atau JIS G 3302), designation, dan metode (triple-spot versus single-spot) sebelum membandingkan FOB.
Tawaran gagal bila baris seng hanya julukan. Z275 adalah massa. G90 adalah massa dalam ons. 20 um adalah tebal panduan, bukan weigh-strip-weigh. Pembeli coil galvanis DX51D harus menuliskan massa sebagai field PO.
| Missing RFQ field | What the mill will fill | Why the three quotes cannot be ranked |
|---|---|---|
| Standard omitted (“GI / HDG coil”) | EN 10346, ASTM A653, or a mill card | Z140 and G60 are not the same test gate |
| Designation omitted (“heavy zinc”) | Z80, Z140, or leftover Z100 | Outdoor duty and indoor ducting share one price |
| Test method omitted | Triple-spot average, single-spot, or a handheld gauge | A passing micron photo can fail ASTM A653 Table 1 |
| Which surfaces | Total both sides vs one-side minimum | Differential coating hides a thin exposed face |
| ISO 9223 site class | Whatever zinc the mill already has | C2 indoor stock is sold into a C4 coastal PO |
Tulis coating sebagai blok salin. ASTM G90 bukan slogan “heavy zinc”. Grade forming tetap terpisah: coil galvanis G550 adalah kelas yield, bukan kelas seng.
Apa yang benar-benar dibekukan Z80, Z140, dan Z275
Designation pada lembar galvanis kontinyu adalah massa minimum total kedua sisi, biasanya triple-spot test. Itu tidak menjamin setengah seng di tiap sisi dan bukan 100% setara antar EN, ASTM, dan JIS.
| Designation | System buyers actually write | Minimum total both sides (triple-spot) | Typical guidance thickness per side | Do not treat as |
|---|---|---|---|---|
| Z80 | Commercial offer; often JIS-style Z08 | 80 g/m2 if the mill accepts that code | About 5-6 um guidance only | An EN 10346:2015 listed zinc class |
| Z140 | EN 10346 Z140 | 140 g/m2 | About 10 um | ASTM A653M Z120 or Z180 |
| Z275 | EN 10346 Z275 / ASTM A653M Z275 | 275 g/m2 | About 20 um | A batch-galvanized ISO 1461 micron call-out |
| G60 | ASTM A653 G60 | 0.60 oz/ft2 (about 183 g/m2) | Guidance only | Z140 |
| G90 | ASTM A653 G90 | 0.90 oz/ft2 (about 275 g/m2) | About 20-21 um if the split is even | A free upgrade from Z140 |
Kartu EN 10346:2015 mencantumkan seng Z100 sampai Z600, Z140 = 140 g/m2 dan Z275 = 275 g/m2 pada triple-spot. ASTM A653 Table 1 untuk G90 menuntut 0.90 oz/ft2 rata-rata triple-spot, 0.80 oz/ft2 single-spot, dan biasanya tidak kurang dari 0.32 oz/ft2 di satu sisi (sekitar 40%). GalvInfo: 1.00 oz/ft2 = 305 g/m2, jadi G90 duduk di samping Z275. Samping bukan identitas. Z80 sering komersial / JIS Z08 dan ditandai tidak termasuk pada tabel EN 10346 yang mulai Z100. G60 sekitar 183 g/m2; itu bukan Z140 (140 g/m2).
ISO 9223 adalah field lokasi, bukan julukan pabrik
Umur seng mengikuti ketebalan pada atmosfer tertentu. Itu tidak mengubah Z275 menjadi garansi pesisir, dan tidak mengubah ISO 9223 C5 menjadi kode yang bisa di-rolling pabrik.
| ISO 9223 class buyers name | Typical atmosphere language | What a GI coil RFQ should freeze instead of a year-life slogan |
|---|---|---|
| C1-C2 | Heated indoor / rural inland | Z80 or Z100 only if the drawing is indoor and cut edges stay dry |
| C3 | Urban / light industrial / low-salinity coast | Z140 or Z275 as the project names; not “Z80 heavy zinc” |
| C4-C5 | Industrial wet / moderate-to-high chloride | Z275 is often still a light coil coating; ask whether AZ, ZM, or batch HDG is the specified system |
| CX | Offshore / extreme | Continuously galvanized DX51D coil is rarely the specified system |
Literatur produsen yang memetakan seng EN 10346 ke EN 55634-1 menempatkan Z275 (sekitar 20 um per sisi) di sekitar C3, bukan C5. Perlakukan sebagai panduan pabrik. Coil PPGI tetap butuh DX51D+Z140 atau DX51D+Z275 pada substrat. RAL 9002 adalah warna, bukan massa. 55% Al-Zn atau ZAM adalah sistem lain.
Kimia, grade forming, dan tebal masih di coil yang sama
Massa seng duduk di substrat baja. Stempel Z275 tidak membekukan DX51D, dan stempel DX51D tidak membekukan Z275. Tuliskan keduanya pada baris RFQ yang sama.
| Substrate family | Standard language | C % max (typical table) | Mn % max | P % max | S % max |
|---|---|---|---|---|---|
| DX51D | EN 10346 DX51D+Z | 0.18 | 1.20 | 0.12 | 0.045 |
| S550GD | EN 10346 S550GD+Z | 0.20 | 1.70 | 0.10 | 0.045 |
| SGCC | JIS G 3302 SGCC | Confirm ordered edition | Confirm | Confirm | Confirm |
| CS Type B | ASTM A653 CS Type B | Confirm ordered edition | Confirm | Confirm | Confirm |
Pakai tabel sebagai pengingat dan konfirmasi edisi EN 10346. Jangan anggap DX51D, SGCC, dan CS Type B 100% setara. Tensile DX51D sering 270-500 MPa; C 0.18 / Mn 1.20 / P 0.12 / S 0.045 pada tabel tipikal.
| Family | Yield / tensile direction (confirm ordered edition) | Elongation / forming | Coating note |
|---|---|---|---|
| DX51D+Z | Tensile often discussed as 270-500 MPa; no 550 MPa min | Elongation is the acceptance field for profiling and bending | Z80 to Z275 can all sit on this grade |
| SGCC | Commercial GI; not a 550 MPa class | Same job family as DX51D on many export offers | JIS coating codes (Z08, Z12, Z27) are not EN nicknames |
| S550GD+Z / mill G550 | Yield min 550 MPa class | Low leftover stretch; high-rib roofing | Zinc class is still a separate field |
| SGCH full hard | Full-hard GI, not DX51D | Poor lock-seam stretch | SGCH carbon steel coil is a hardness family, not a zinc family |
| Coil field | What to freeze on the PO | Typical export range (confirm mill card) | Bid failure if omitted |
|---|---|---|---|
| Thickness basis | Base metal or total coated product | 0.30-1.50 mm common for GI coil | 0.45 mm G550 rib vs 0.45 mm DX51D base metal |
| Thickness tolerance class | EN 10143 / ASTM A924 class as ordered | Special vs normal class | Mill ships the looser class at the same price |
| Width / edge | Mill edge or slit edge; width +0/-0 or named | 600-1250 mm common | Slit-edge camber on a lock-seam line |
| Coil ID / OD / mass | ID 508 mm or 610 mm; max OD; kg per coil | 3-8 MT on thin GI; 20GP payload 25-28 MT | Eye-to-wall coils that will not fit the cradle |
Pola meja ekspor Shandong: PI menulis DX51D+Z, Z80/Z140, 0.40 x 1000. Pabrik memuat Z80. MTC mencetak massa total di bawah 100 g/m2. Fabrikator di lokasi C3 klaim white rust. Tahan coil jika PO menamai Z140 dan sertifikat tidak membuktikan. Tebal 0.30-1.50 mm, lebar 600-1250 mm, ID 508/610 mm, 3-8 MT untuk GI tipis.
Permukaan, packing, dan MTC harus menamai coating
Bahasa permukaan menyembunyikan coating ringan. Zero spangle dan regular spangle tidak mengubah Z140 menjadi Z275. Passivasi dan oiling mengubah white rust di 20GP; itu tidak menambah gram seng.
| Surface / coating field | Options to freeze | Why it belongs next to Z80 / Z140 / Z275 |
|---|---|---|
| Spangle | Zero / minimized / regular | Appearance only; not a mass upgrade |
| Surface quality | As-coated A / improved B (EN language) | Skin-pass for painting is not extra zinc |
| Passivation | Cr-free / chromated / none | Unpassivated Z275 still white-rusts in a hot container |
| Oiling | Dry / light oil | Dry coil + long sea transit is a packing claim waiting to happen |
| Differential coating | Equal both sides vs named g/m2 per face | A thin exposed face fails first |
| Packing field | Seaworthy default to name | Hold point |
|---|---|---|
| Wrap | VCI paper + plastic + outer steel sheet | Bare OD wrap on a rainy yard |
| Edge | Inner and outer metal edge protectors | Cut OD that starts white rust in week one |
| Straps | At least 3 circumferential + 4 radial steel straps | Collapsed eye after stuffing |
| Desiccant | Named silica-gel mass per coil | ”Anti-rust packing” with no packet count |
| Stowage | Eye-to-sky or eye-to-wall; wooden cradle; 1x20GP 25-28 MT | Mixed stowage that rubs the zinc off the OD |
| MTC 3.1 field | Must print | Reject / hold if |
|---|---|---|
| Standard + coating designation | EN 10346 Z140, ASTM A653 G90, or the PO string | ”GI” or “Z80/Z140” as a range |
| Coating mass | Total both sides, unit g/m2 or oz/ft2 | Micron-only remark with no mass |
| Test method | Triple-spot and/or single-spot as ordered | Warehouse gauge photo only |
| Heat / coil identity | Heat number matching stencil and packing list | Heat on MTC, different heat on tag |
| Substrate grade + mechanicals | DX51D / SGCC / CS plus tensile / elongation as ordered | Coating matches, grade swapped |
| Inspection representative | EN 10204 3.1 issuer independent of production | Unsigned mill list |
SGS, BV, atau TUV dapat memotong kupon ASTM A90/A90M. OD mengkilap bukan uji itu. Praktik dokumen EN 10204 3.1 adalah jejak kertas.
Blok salin untuk purchase order massa coating
Tempel blok ini ke RFQ. Hapus opsi yang tidak Anda inginkan. Jangan sisakan garis miring antara Z80 dan Z275.
- Product: continuously hot-dip galvanized steel coil, not batch HDG after fabrication.
- Standard / grade: EN 10346 DX51D+Z (or ASTM A653 CS Type B / JIS G 3302 SGCC as the drawing names). Not dual-stamped against S550GD or mill G550 unless accepted.
- Coating designation: Z140 or Z275 or G90 — one code only. Z80 only if the drawing is indoor and the standard is not EN 10346.
- Coating test: minimum total both sides by triple-spot; single-spot gate as in the ordered ASTM A653 / EN 10346 table. Weigh-strip-weigh referee (ASTM A90/A90M or the EN method named).
- Split: equal both sides unless a differential coating is named per face.
- Surface: zero or regular spangle; Cr-free passivation; oiled or dry as named.
- Size: thickness (state base metal or total coated) x width x coil ID 508/610 mm; EN 10143 / ASTM A924 tolerance class.
- ISO 9223 site class on the RFQ header (C2 / C3 / C4), not as a mill zinc nickname.
- Documents: EN 10204 3.1 MTC with heat number, coating mass, test method, and substrate mechanicals. TPI coupons allowed.
- Packing / lot: VCI + edge guards + named strap count; 1 x 20GP (25-28 MT); dispatch 7-15 days for standard sizes.
Jika pabrik menjawab “Z80 equivalent to Z140” atau “G90 / Z140 same”, penawaran tidak sebanding. Kirim ulang bloknya. SGCH full hard adalah keluarga kekerasan, bukan seng. Cerita pantai 25 tahun pada PI Z140 bukan spesifikasi.
Kesimpulan
Z80, Z140, dan Z275 adalah designation massa seng pada coil galvanis kontinyu. Bukan julukan pabrik dan bukan ekuivalen 100% antara EN 10346, ASTM A653, dan JIS G 3302. Bekukan satu designation, satu metode, satu grade substrat, dan satu kelas ISO 9223. Lalu baca empat field itu pada EN 10204 3.1 MTC sebelum stuffing.
Merencanakan pesanan atau butuh verifikasi teknis?
Jika Anda sourcing coil baja galvanis (Z80 / Z140 / Z275 atau G90) atau butuh pabrik mengonfirmasi massa terhadap atmosfer proyek:
- Penawaran teknis cepat: 1 x 20GP (25-28 MT), 7-15 days. Formulir RFQ online
- Jaminan mutu: EN 10204 3.1 MTC. SGS, BV, TUV.
- Inquiry mendesak: WhatsApp +86 151 5311 2221
