What should I send a PP plastic protective case factory for a quote?

Five items: internal dimensions, wall thickness or load rating, minimum temperature, foam layout, quantity with target date. Those fix grade, tonnage and cavities.

How low can the MOQ go?

About 300 units for a single-cavity steel tool; below that, amortisation passes 40% of the price and a prototype is cheaper. Rotomoulding has no floor, but tolerance widens to 1.5 mm.

Can tooling amortisation be removed from the price?

Yes, if the buyer pays for the tool outright and the contract assigns ownership. Otherwise, fix the cumulative volume at which charging stops.

Why is one quote 40 days and another 60?

Trials. Forty days means a mature design passing T1 first time; sixty means two revision rounds on latch fit or shrinkage. Ask how many free revisions follow T1.

What matters on a small trial order?

Same batch, same tool, no colour-change stand-ins. Record measured internal dimensions and latch force at first-article approval, and tie the trial tooling fee to the volume price.

PP Plastic Protective Case Factory: Quote, MOQ and Lead Time

Quick answer: At a PP plastic protective case factory, three documents decide the price: a quote split into resin, moulding, tooling and finishing; a step ladder on 50, 300, 1,000 and 3,000 units; and a lead time split into tooling, trials, run and packing.

How a PP Plastic Protective Case Factory Quotes the Work
Injection Moulding or Rotomoulding
Tonnage, Cavities and Daily Output
MOQ Tiers and How Step Pricing Works
Splitting Lead Time Into Four Stages
FAQ

1. How a PP Plastic Protective Case Factory Quotes the Work

Two quotes for one case, 268 and 197, usually differ in scope, not margin: one buries tooling in the unit price, the other lists it; one includes foam, the other sells a bare shell. Ask a PP plastic protective case factory to split the number four ways.

Line	Basis	Share	Ask this
Resin	Weight x price x 1.03	38% to 45%	Grade, spot or quarterly
Moulding	Rate / cavities / cycle	22% to 28%	Setup included
Tooling	Tool cost / quantity	10% to 18%	Cap and refund
Finishing	Foam, print, assembly	8% to 15%	Die-cut or routed

Four items usually surface after the tool is cut: colour masterbatch, flame-retardant grades, drop reports, a second revision.

2. Injection Moulding or Rotomoulding

PP sits at 0.90 to 0.91 g/cm3, about 15% lighter than ABS, so the same volume uses less resin. It resists acids and salt solutions, not aromatic solvents; embrittlement runs near minus 10 C for homopolymer, below minus 35 C for block copolymer.

PP plastic protective case factory output: black case open on white, two cam latches on the lid, base foam cut to wrench and socket profiles

Injection moulding: 2.2 to 3.5 mm walls, 45 to 140 seconds a shot, plus or minus 0.5 mm, steel tool 120,000 to 350,000 CNY. Rotomoulding: 3 to 6 mm walls, 25 to 40 minutes a cycle, plus or minus 1.5 mm, aluminium tool 30,000 to 60,000 CNY. Tooling differs three to five times, processing 1.8 to 2.5 times the other way, so the crossover sits at 300 to 500 units.

3. Tonnage, Cavities and Daily Output

Clamping force must match projected area. At 35 MPa cavity pressure, 250 tonnes covers 0.07 square metres, 450 tonnes 0.126, 650 tonnes 0.182, 1,000 tonnes 0.28. Undersized tools flash; oversized ones lose life.

Daily output at a PP plastic protective case factory is 22 hours at 0.85 efficiency, times cavities, divided by cycle time. A four-cavity tool costs 2.6 times a single and a changeover takes 2.5 hours, so under 5,000 units amortisation worsens.

4. MOQ Tiers and How Step Pricing Works

MOQ is a ladder: under 50 units means a prototype or colour change; 300 justifies a single-cavity tool; 1,000 opens two cavities; 3,000 starts the four-cavity talk. About 70% of the gap is tooling, 30% setup.

Tier	Quantity	Tooling	Price vs 1,000	Delivery
Sample	1 to 10	Prototype	3.2 to 4.5x	7 to 12 days
Small	50 to 200	Single-cavity steel	1.35 to 1.8x	25 to 35 days
Medium	300 to 1,000	Single or two cavity	1.0 base	20 to 28 days
Large	2,000 to 10,000	Two or four cavity	0.82 to 0.9x	15 to 22 days

A 120,000 CNY tool amortises to 1,200 CNY a case at 100 units, 120 at 1,000, 12 at 10,000, while resin and machine time barely move. Lock quantity, then ownership: if a PP plastic protective case factory owns the tool, fix where charging ends.

5. Splitting Lead Time Into Four Stages

A single lead-time figure hides where risk sits: tooling slips on drawings, trials on revisions, production on scheduling, packing on foam arrivals.

Stage	Work	Days	Typical slip
Tooling	Review, roughing, CNC, EDM	18 to 25	Drawing change, EDM queue
Trial	T1 shot, inspection, revision	5 to 7	Warp, latch mismatch
Production	First 500 with first article	12 to 18	Machine booked elsewhere
Packing	Foam, cartons, pallets	3 to 4	Foam queue, pallet shortage

The four total 38 to 54 days; a repeat order on an existing tool ships in 20 to 28. Peak months push slots back two weeks, so plan on plus 14 days.

Conclusion

Three documents decide a purchase: a four-line quote, a ladder anchored on tooling amortisation, and a lead time split by stage. The second tenfold jump buys far less than the first. Settle those numbers before negotiating with a PP plastic protective case factory.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.