A metal casting foundry looks the same from the parking lot whether it is excellent or about to cost you a quarter. The difference is inside, at eight specific stations. This is the route GW walks when we qualify a foundry or check on one, and what we are looking for at each stop.
1. Raw material
Foundries melt a charge of pig iron, scrap, and returns. What is in the scrap pile ends up in your part. We look at how incoming material is sorted, stored, and identified, and whether the foundry can trace a heat back to its charge.
2. Pattern shop and tooling storage
Your pattern is your part's future. We check how tooling is labelled, stored, and inspected between runs, and whether repairs are logged. Customer-owned tooling should be identifiable at a glance and untouched by anyone else's job.
3. Sand system
Moisture, compactability, and bond strength, tested each shift, with the results posted. Poor sand control is the most common root cause of the porosity and inclusions that surface later on a machined face.
4. Moulding and core making
We watch a mould being closed: core placement, venting, mould hardness, and whether the crew is working to a written setup for the job or from memory.
5. Melting and treatment
Furnace temperature and chemistry checked before every pour, and for ductile iron, the magnesium treatment timed and verified. This station decides whether a grade is met or missed.
6. Pouring and cooling
Pouring temperature, pour time, and how long the casting stays in the mould before shakeout. Rushing this stage saves the foundry minutes and costs the buyer hardness and distortion.
7. Cleaning and finishing
Gate and riser removal, grinding, shot blast, and the heat treatment or machining that follows. We look for parts identified by job and lot at every step, so a problem can be contained rather than chased.
8. Inspection and shipping
The last stop is the one that reaches you. Dimensional layout against the print, test bar results filed with the lot, packaging that protects machined faces. Parts that ship with documentation are parts that were inspected; parts that ship without it may have been.
Why we walk it
GW does not operate the foundry. We qualify it, audit it, and manage it — because the buyer holds GW responsible for the part, wherever in the world it was poured. That is the arrangement, and it is why the floor walk matters.