The Aluminum Turnings That Wouldn't Settle
A machine shop delivers 38,000 lb of mixed aluminum turnings and chips, oil-wet, in gaylords. Your buyer quoted it as "mixed aluminum turnings" at a price assuming 88% metallic recovery and no moisture deduction. On arrival the pile is visibly wet with cutting fluid, and a quick hand squeeze leaves oil on the glove. A small lab sample dried at 220°F for two hours shows 6.8% moisture and oil by weight. The material also contains a visible fraction of steel chips from a mixed-metal machining cell - perhaps 3–5% by eye. Your downstream consumer pays on recovered metallic aluminum only, deducts for moisture above 2%, and rejects loads with more than 1% ferrous contamination unless it is magnetically separated before delivery. The load has been on your pad for nine days accruing nothing.
1. Quantify the value leakage and decide the disposition path.
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Start with the dry-weight math. 38,000 lb × 6.8% = 2,584 lb of moisture/oil. If the quote assumed 88% metallic recovery on an as-received basis, the buyer effectively priced 33,440 lb of metal. The true dry metallic is 38,000 − 2,584 = 35,416 lb, and that still includes 3–5% ferrous. At 4% ferrous, about 1,417 lb is steel, leaving roughly 34,000 lb of aluminum - versus the 33,440 lb assumed, so the moisture and ferrous roughly offset on a pure metal-count basis. The real loss is the moisture deduction: the consumer deducts above 2%, so 4.8% of 38,000 lb ≈ 1,824 lb is deducted at the aluminum price, plus the ferrous is paid at steel (or not at all).
Disposition: do not ship as-is - the >1% ferrous triggers rejection. Run the load across a magnetic separator (belt magnet or drum) to pull steel chips, then re-sample for moisture after separation. Separated turnings can go to the aluminum consumer; the steel chip fraction goes to ferrous. Nine days of dwell is pure carrying cost - get it moving.
2. The buyer wants to renegotiate the price downward retroactively. What is your position, and what process change prevents a repeat?
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The quote was made on an assumption (88% recovery, no moisture deduction) that the material did not meet. The buyer is entitled to adjust to actuals, but not to reprice the whole load as if it were a different grade. Position: settle on measured actuals - dry-weight metallic after magnetic separation, moisture deducted per the consumer's schedule - and document the assay. Do not accept a blanket downgrade to a lower grade name.
Prevention: (1) Require a moisture and ferrous screen on any oil-wet turnings before quoting - a two-hour dry at 220°F and a magnet pull are cheap. (2) Quote turnings on a dry-metallic basis with an explicit moisture deduction clause above 2%. (3) Require the machine shop to segregate steel from aluminum at the cell, or price the mixed stream as mixed. (4) Cap dwell time on the pad - nine days of unprocessed inventory is a process failure, not bad luck.