How do I verify monthly capacity at a plastic case manufacturer China?

Answer: Calculate daily output from force, cycle time and effective hours, then multiply by working days. A calculated 29,000 against a stated 30,000 is normal; 8,000 means subcontracted work.

Can MOQ drop below 300 pieces?

Answer: Yes, at the cost of a setup charge; 300 pieces run about 20 percent dearer than 1,200.

Should tooling be paid in full up front?

Answer: On a first order that is simpler, if title and storage are written in. Paying in stages, tie each payment to a passed trial.

What slips most often inside 21 days?

Answer: The insert. Foam converted outside runs on another schedule, so send the drawing two weeks ahead.

Plastic case manufacturer China: 6 presses, 800 tons, 21 days

Quick answer: A plastic case manufacturer China quotes capacity by the month, yet capacity is arithmetic: force against projected area, cycle time and hours give a figure you can test.

Three numbers behind a capacity claim
Own plant or trading office: six checkpoints
How MOQ and tooling ownership land in the price
Working back from 21 days and payment terms
Five quote styles that look cheap
FAQ

1. Three numbers behind a capacity claim

A plastic case manufacturer China quoting thirty thousand units a month has said nothing until you ask which presses run. Three numbers settle it: force against projected area, cycle time, effective hours.

At 400 kg/cm² cavity pressure an 800-ton press covers 0.20 m². A 500×350 mm case with runners is 0.18 m², needing 720 tons, so 800 tons leaves a ten percent margin.

Press	Projected area	Pieces per day
530 tons	0.13 m²	480
800 tons	0.20 m²	377
1,300 tons	0.32 m²	305

Daily output follows: 22 hours divided by 210 seconds gives 377 shots on one cavity. Three 800-ton presses make 1,130 pieces a day, or 29,000 over 26 working days, exactly the stated thirty thousand.

Past the tonnage limit only two explanations survive: subcontracted work, or a two-cavity tool. Ask how many cavities and how many seconds the cycle grows, and put the count in the contract annex. A plastic case manufacturer China that will not name a cavity count is quoting somebody else's presses.

2. Own plant or trading office: six checkpoints

A company with export in its name may not own one injection machine. Six points on the floor settle it.

Plastic case manufacturer China: frosted translucent case open at an angle, two latch seats in the lid, cables inside

Machine plate: photograph tonnage and serial, then match the serial to the schedule board.
Dryer: hopper setting should suit the resin; polypropylene dries at 80℃ for two hours.
Tool store: ask for your mould's rack position, then walk to it.
Leak station: is there a test tank, and is the sampling rate posted.
Packing line: marks and carton labels printed in house, or bought ready-made.
Regrind: sprue ratio at 15 or 30 percent decides cold-weather brittleness.

The machine plate and tool store are hardest to fake. A tonnage that contradicts the schedule means the order changed hands, and a rack you cannot reach means the mould lives elsewhere. A plastic case manufacturer China buyers shortlist that explains both with the workshop manager away has answered the question.

A factory sends serial photos and shot counts; a trading office sends a showroom.

3. How MOQ and tooling ownership land in the price

MOQ falls out of changeover time and cavity count. A single-cavity tool for a 500×350 case takes 4.5 hours to change, a two-cavity tool six hours. Change twice a day and 40 percent of output disappears, so small orders queue or pay a premium.

Quantity	Tooling cost	Per piece	What it suits
500 pieces	38,000 CNY	76 CNY	Trial run
1,200 pieces	38,000 CNY	31.7 CNY	First order
3,000 pieces	38,000 CNY	12.7 CNY	Replenishment

A 38,000 CNY tool over 500 pieces adds 76 CNY to each case, more than the case itself. That is why a plastic case manufacturer China sets a floor at 300 pieces and still recommends 1,200 for the first order, where the spread falls to 31.7 CNY.

Ownership needs three lines: title to the buyer, free storage for 24 months, and who pays removal when production stops. Without the third, the mould costs a second tooling price the year you claim it.

4. Working back from 21 days and payment terms

Twenty-one days is standard; only the queue compresses.

Plastic case manufacturer China: grey case open on a wooden bench, foam lid insert with cut pockets, two latches

Read machine occupancy, not order numbers. If an 800-ton press is booked by three orders before month end, your job lands in the next changeover window. A new tool needs two trial rounds, an old one needs flash trimmed, and each costs a day. Copolymer resin is in stock while a custom masterbatch takes seven days. Foam converted outside runs on its own clock, often longer than moulding. String the four stages together and the slack sits only in the queue.

Payment runs 40 percent deposit, 50 percent before shipment, 10 percent thirty days after arrival. A plastic case manufacturer China supplier grants those thirty days past 800,000 CNY of annual spend; new buyers instead find the cost of money in the price, about 6 percent annualised.

5. Five quote styles that look cheap

Five quotes for one case can differ by 40 percent, and the gap is what nobody wrote down.

Insert not priced: bare case quoted, foam later, the unit looks 18 percent cheaper.
Tooling folded in: 12 CNY on the first 3,000 pieces, none refundable.
Tax in, freight out: 13 percent VAT included, crating apart.
Two-cavity lead time: trials single-cavity, production two, a week apart.
Verbal promises: 96 hours of salt spray and a five-high stack, never on paper.

The most expensive of the five is the last. With no written criterion, rework costs more than the discount, so push all five onto the line items before comparing one plastic case manufacturer China offer with the next.

Conclusion

Verification is three numbers and six checkpoints: if output adds up and the tool store is walkable, there is a basis to talk. The difference between one plastic case manufacturer China and the next is not whose figures look better but who opens the press plates and the schedule. Settle 800 tons against 0.20 m², 38,000 CNY of tooling over 1,200 pieces and 21 days in stages, and most quote traps close by themselves.

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.