Can I order an EMI shielding case below 100 units?

Answer: Yes, but tooling is billed separately and the date follows the plant schedule. Colour and wall thickness also vary more between units.

Should tooling be a separate line or absorbed into the unit price?

Answer: Beyond three years a separate line is cheaper from year two; for a trial build, absorption is easier on cash if ownership and transfer terms are in the contract.

The quote has no attenuation figure. Can we still sign?

Answer: Not advisable. An EMI shielding case needs attenuation written as frequency plus value, such as 60 dB at 1 GHz, with the test port and sampling ratio named.

Which stage slips most in a 45 day lead time?

Answer: Conductive coating. It is outsourced, cure runs on its own schedule, and a re-spray costs a week, so attach the spray date to the contract.

EMI Shielding Case Quotes: MOQ, Tooling Ownership, Lead Time

Quick answer: Most of the spread in EMI shielding case quotations comes from tooling ownership, minimum order quantity and outsourced conductive coating rather than from the shielding layer itself, so one drawing can attract prices that differ by a factor of two. Fix the fields, schedule and payment terms before the inquiry goes out.

Write a Duty Card Before You Ask for a Quote
MOQ and Tooling Ownership
Split the Lead Time Into Four Stages
Five Places a Quote Grows
Payment Milestones and the Factory Visit
FAQ

1. Write a Duty Card Before You Ask for a Quote

Last winter a batch of EMI shielding case units travelled 1,200 km by road. The cargo bay peaked at 40°C by day, fell to minus 8°C at night, and the load was handled four times. One drawing went out; quotes came back between 2,600 and 5,100 yuan per unit.

The drawing gave a 600 x 400 x 220 mm cavity, a 6 mm wall and 60 dB at 1 GHz, and said nothing about restraint, gaskets, salt spray or packaging. Every missing field is one the supplier fills cheaply for itself.

Field	Specify	Impact if omitted
Transport	Strap over the lid, pallet stacking	Lid ribs deleted, 120 yuan lower
Climate	Minus 8°C to 40°C, 85% RH	Gasket down a grade, 90 yuan lower
Shielding	60 dB at 1 GHz, test port	No gasket, 260 yuan lower
Delivery	Carton or pallet, label content	Packaging extra, 40 yuan higher

An EMI shielding case ordered against a vague request for good corrosion resistance is never quoted honestly; one specified at 96 hours of neutral salt spray is.

2. MOQ and Tooling Ownership

Minimum order quantity is the first number to settle and the easiest to leave blurred.

EMI shielding case: grey rotomolded cases held by a black strap inside a white van cargo bay, ratchet latch closed, ribbed walls

A steel mould costs near 38,000 yuan, an aluminium one near 22,000. Spread over 200 units the tool adds 190 yuan per case; over 50 units it adds 760.

Tooling either sits on its own line or is absorbed into the unit price. The difference is ownership.

A separate line means the buyer owns the mould and can move it when the programme ends. Absorbed tooling is a supplier asset that cannot travel, so a second tool is paid twice. Two questions decide the route: how long the EMI shielding case stays in the catalogue, and whether the structure may change. Beyond three years the separate line wins. The unit price then carries no amortisation. Name the maintenance interval and who pays for corrosion too.

Once ownership is clear, MOQ can move: 200 units is the economic batch for a mould change.

3. Split the Lead Time Into Four Stages

The gap between 45 days and 70 days is rarely machine speed. It is one stage waiting on another.

Stage	Days	Usual bottleneck
Tooling and first shot	12	Cavity radii revised after sign-off
Rotomoulding	8	Mould queue, colour change
Conductive coating	10	Spray booth, coating cure
Assembly and test	7	Gasket delivery, sampling

The stages total 37 days, and five days of freight bring it to 42. A 45 day promise is reasonable; a 30 day promise usually means the coating stage was folded into a batch already running.

Ask for a production date, not a total. Where coating is outsourced, that date sits on a third party's board.

4. Five Places a Quote Grows

A readable quote is a signable contract.

EMI shielding case: close-up of an off-white latch on a closed case in an airport terminal, blurred passengers and seating behind

Gaskets quoted separately. A 600 mm cavity with twin runs uses 2.4 m, adding 60 yuan by the metre.
Coating by area. Paint priced on total surface grows on ribs, and real use runs 25% above projection.
Testing per point. A sweep across 1 GHz and 10 GHz costs about 800 yuan, sampling on top.
Sample fee offset. Whether the charge is credited against the first order belongs in the notes.
Packing and marking. Crate, pallet, marks and labels need line by line confirmation.

Fight all five on price or not, but get all five in writing: a short quotation breeds change orders.

5. Payment Milestones and the Factory Visit

Milestone	Share	Released by
Signature	30%	Tooling and first article
Before shipment	40%	Sampling report, loading photos
30 days after arrival	25%	Quantity and cosmetic check
12 month warranty	5%	Gasket and latch claims

That final 5% decides whether anyone answers the phone when a gasket hardens. Failures in an EMI shielding case rarely appear on day one; compression set and slack latch pins surface between month eight and month twelve.

A factory visit needs three stops: a spray room with its own cure zone, the calibration date on the salt spray chamber, and a fixed test port. If those line up, the process cost in the quote has an origin.

Conclusion

The hard part of buying an EMI shielding case is not the data sheet but the six fields around it: duty, order quantity, tooling ownership, lead time stages, quote basis and payment. Fix those and a two-to-one spread narrows to within ten percent. Write the duty card, split the schedule, price gaskets and testing separately, and only the unit price is left to argue about. Done in that order, an EMI shielding case inquiry turns into a comparison of terms.

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.