Introduction
A distributor in Dubai, a roofing fabricator in Lagos, and a project buyer in Jakarta often send one email that names three products at once: GI coil, PPGI coil, and carbon steel pipe. The mill replies with one unit price list. The GI line has a zinc mass. The PPGI line has a RAL shade. The pipe line says Grade B. None of the three offers can be compared with the next mill, because each desk filled the blanks differently.
This freeze list is for buyers who source those three families together: coil stockists, roofing and cladding fabricators, and pipe importers who also buy coated coil for the same project or warehouse. It is a specification tear-down, not a product comparison. Use the steel RFQ template for the commercial wrapper (quantity, Incoterms, ports). Come back here to freeze the three technical blocks so the wrapper has something real to wrap.
Why Mixed RFQs Collapse Into Incomparable Quotes
Mills do not invent malice when a mixed inquiry is thin. They invent defaults. Those defaults are cheap to quote and expensive to unwind after the container is stuffed.
| Missing field on a mixed RFQ | What the mill often fills in | What you cannot compare later |
|---|---|---|
| GI coating mass | Commercial zinc, unnamed | Cut-edge life and coil weight |
| PPGI paint system | Color only, PE assumed | Fade, chalking, and film cost |
| Pipe process and standard | Grade B, process open | Welded versus seamless, A53 versus A106 |
A USD 15 per ton gap on mixed cargo is often packing, theoretical weight, or an unnamed PE topcoat, not the melt. If the inquiry still looks like one line, split it before you rank suppliers.
Split The Inquiry By Product Form First
Write three headings in the same RFQ: GI coil, PPGI coil, carbon steel pipe. Shared fields (destination port, shipment window, payment, inspection hold points) sit above the split. Technical fields do not.
Step 1: name the form. Coil is not pipe. Bare GI is not PPGI. If the warehouse will slit GI and send PPGI to a roll-former, say so. Forming route changes oil, film, and packing.
Step 2: name the standard family per form. GI coil usually sits in ASTM A653, EN 10346, or JIS G3302. PPGI still needs that metallic substrate plus a paint system. Pipe needs ASTM A53, ASTM A106, or API 5L, not a Grade B nickname.
Step 3: name quantity and weight basis per form. Theoretical coil weight and actual pipe scale weight cannot share one unit price. State MT, pieces, or meters, and whether coil weight is theoretical or scale.
Do not treat GI, PPGI, and pipe as interchangeable stock. A mill that dual-stamps pipe or substitutes GL under a GI line is offering a commercial convenience. The purchase order still has to name what you will accept.
| Product form | Freeze before comparing quotes | Do not leave as a nickname |
|---|---|---|
| GI coil | Standard, zinc mass, thickness basis, oil or dry-ship | “galvanized coil” with no Z or G90 class |
| PPGI coil | Substrate zinc mass, paint family, film build, RAL or sample | Color-only PPGI |
| Carbon steel pipe | Specification string, seamless or welded, ends, weight basis | Grade B with process open |
GI Coil Block: Coating Mass, Surface, Thickness Basis
The GI block is the metallic-coated coil the fabricator will form, slit, or hold as bare stock. Color language does not belong here.
Freeze at least:
- Product form: GI coil (not sheet, not PPGI)
- Standard and grade: ASTM A653, EN 10346, or JIS G3302, with the ordered grade
- Zinc coating mass: Z180 or Z275, or G90 class if that is the project language
- Thickness and width with tolerance, and whether thickness is base metal or total product
- Surface: spangle, passivation, oil or dry-ship rule
- Coil ID, OD or max coil weight, and slitting notes if the coil will be cut
- Packing for sea freight and certificate scope
The GI coil purchase-order checklist walks each of those fields. On a mixed RFQ, the failure mode is shorter: the GI line inherits PPGI color talk and loses zinc mass. Keep Z180 / Z275 / G90 on the GI block even when the same email orders painted coil.
PPGI Coil Block: Substrate, Paint System, Color Is Not Enough
PPGI is a zinc-coated substrate plus organic layers. A RAL number is one paint field. It is not the product.
Freeze at least:
- Product form: PPGI coil
- Substrate standard and zinc mass (the same ASTM A653 / EN 10346 family as GI, plus a Z or G90 designation)
- Paint family: PE, SMP, HDP, or PVDF, with top and reverse film build
- Color reference: RAL or an approved sample, plus gloss
- Thickness, width, coil geometry, protective film if the coil will be formed
- Packing and certificate scope
The PPGI specification guide is the field-by-field version. On a mixed RFQ, lock the substrate before the color. Cut edges and scratches are still zinc’s job. The PPGI coil product page is the catalog side of that same block.
Carbon Steel Pipe Block: Standard, Process, Ends, Weight
Pipe on a mixed RFQ is where Grade B does the most damage. ASTM A53, ASTM A106, and API 5L can all show Grade B on a mill quote. They are not one specification.
Freeze at least:
- Specification string: ASTM A53, ASTM A106, or API 5L, with type if A53 (F, E, or S)
- Process: seamless or welded (ERW, LSAW, SSAW named if welded)
- Size: NPS or OD x wall, length, ends (plain, beveled, threaded)
- Coating: black, varnish, or galvanized only if the project names it
- Tests and NDT the mill must print
- Weight basis: theoretical versus scale, and whether galvanized pipe is weighed after coating
- EN 10204 3.1 MTC with the exact specification string
The ASTM A106 vs ASTM A53 buyer guide is the place to stop silent dual-stamps. Do not fill an A106 line with A53 Type E because both say Grade B. Do not leave process blank and hope the mill ships seamless.
Shared Documents, Packing, And Arrival Checks
After the three blocks, freeze the documents that tie the cargo together. This is the part mixed RFQs usually copy from a previous coil-only order and then forget to extend to pipe.
- Certificate type: EN 10204 3.1 MTC, with heat number traceability to coil ID or pipe bundle
- Marking: heat, grade, coating designation or pipe specification, size, and bundle or coil number
- Packing: export sea packing, VCI or wrapping for coil, end caps and bundling for pipe, container loading photos if you will claim rust
- Inspection hold points: mill inspection, third-party PSI only if you will write the instruction and pay for it
- Arrival check: MTC strings versus stencil versus packing list before the cargo leaves the port yard
A certificate that names color and omits zinc mass, or names Grade B and omits ASTM A53 Type E, will not protect a claim. Packing that kept coil dry and left pipe ends open is two different failures on the same bill of lading. The steel export packing guide covers the sea-freight side.
Conclusion
A mixed GI / PPGI / pipe inquiry is three specifications under one commercial header. Split the product forms, freeze zinc mass on GI, freeze substrate plus paint on PPGI, freeze process and specification string on pipe, then lock EN 10204 3.1 MTC, packing, and weight basis so the quotes share a scope. Send the completed freeze list through the request a quote page, or ask for a sample coil and a sample pipe joint before you book a mixed container. The mill certificate, coating designation, and packing list are the documents that make the order auditable. Write them on the RFQ first.
