pWPS generator
A preliminary welding procedure specification to EN ISO 15609-1: give the process, parent material group, thickness and position, and the generator drafts the sheet with edge preparation, filler, gas, current and thermal regime. The sheet downloads as a table and you fill in the rest.
Short answer
A pWPS is the same sheet as a WPS, only before the test: the same fields, but nothing in them is proven yet. You write it, weld a test piece to it, and after the WPQR report it becomes a WPS. The generator below drafts that sheet from your data: edge preparation, filler, gas, current and thermal regime.
Where the numbers come from
The parameters come from the same tables that print the MIG/MAG, TIG and manual metal arc current data elsewhere on the site: filler diameter, current, voltage and gas flow are picked by thickness. Edge preparation is worked out by the same function as the groove calculator — the angle, gap and root face in the sheet are the ones you get there. What the generator adds of its own is the choice of filler and shielding gas by material group, and the arrangement of all of it into the rows of EN ISO 15609-1.
It does not work out heat input: travel speed goes into that, and travel speed is measured on the test piece — the sheet leaves an empty row for it. It does not know your heat: the preheat here is typical for the group and thickness, and the exact figure comes from EN 1011-2 through the carbon equivalent. It does not cover aluminium: that needs 131 and 141 and different parameters, and the site has no tables of that kind yet — guessing numbers in a document that goes to inspection is not on. And above all: it does not qualify the procedure.
From pWPS to WPS
The order is this: you write the pWPS, weld a test piece to it, submit that for testing, get the WPQR report — and only then does the same sheet become a WPS. Until the report exists the document stays preliminary, however carefully it is filled in.
Qualification covers a range rather than a single combination: other thicknesses, diameters and positions that fall inside it need no separate WPQR. That is exactly why the test piece is chosen not for ease but for the range it buys.
Frequently asked questions
How does a pWPS differ from a WPS?
In its fields, not at all — they are the same. The report makes the difference: a WPS has a WPQR behind it confirming that the sheet produces a sound weld, and a pWPS does not have one yet. That is why you weld a test piece to a pWPS, not a product.
Can I weld production work to a pWPS?
Only where a qualified procedure is not required at all. The moment the work is accepted to EN 1090 or ISO 3834 and the client asks for a WPS, a WPQR report is needed — without it the sheet is not a document but an intention.
Why is the heat input row left empty?
Because travel speed goes into it, and travel speed cannot be derived from thickness: it depends on the welder, the position and how the pool runs. The generator gives you current and voltage; you measure the speed on the test piece and work out heat input with the separate calculator.
Why is there no aluminium?
Because it needs different processes (131 and 141), different fillers and different parameters, and the site has no parameter tables for aluminium yet. Putting steel figures here would mean handing inspection a document with wrong data.
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