Which items in an Equipment Case standard need full inspection?

Answer: Class A only, so every unit gets a pressure check.

Why not test pressure straight off the line?

Answer: A warm case cools inside and reads low; soak two hours.

Can a case that leaks after a drop be reworked?

Answer: No. A distorted rim will not seal again.

Does white rust fail salt spray?

Answer: Above 5% of the area. Red rust always fails.

Is one shielding frequency enough?

Answer: No. Seams resonate, so read five points.

Equipment Case Acceptance Standards: Test Items and Verdicts

Quick answer: A clause for an Equipment Case is testable only when it names the item, method, condition, sample size and pass line. Class A takes zero defects, B and C are sampled by AQL, and serial numbers tie results to a batch.

Test Items and Verdict Rules for an Equipment Case
Visual, Dimensional and Latch Checks
Pressure Decay, Drop and Vibration
Salt Spray, Cycle Life and Shielding
Sampling, Documents and Batch Traceability
FAQ

1. Test Items and Verdict Rules for an Equipment Case

A clause saying the finish looks good cannot be measured: name the item, instrument, condition and limit. An Equipment Case sorts items by consequence, with a failed seal or a cracked shell in class A, assembly and life in B, appearance in C. Class A is never sampled, so every unit gets a pressure check; B follows level II, C may drop to S-2.

Item	Class	Method	Pass line
Appearance	C	800 lx, 600 mm, 45 degrees	No crack, sink 0.5 mm or less
Size	B	Caliper, three points	Outside ±2 mm, cavity ±1.5 mm
Pressure decay	A	Charge to 5 kPa	30 s, decay 0.2 kPa or less
Drop	A	1.2 m concrete, ten drops	No crack, decay 0.3 kPa
Stack	B	250 kg on lid, 24 h	Set 3 mm or less

Each row needs a position sketch, an instrument number and a signatory; without the number, two calipers give two verdicts.

2. Visual, Dimensional and Latch Checks

Fix the light first: 800 lx, 600 mm, 45 degrees. Sink depth is a 0.5 mm feeler that must not enter; flash on the parting line runs to 0.3 mm before rework.

Equipment Case: a wide latch on a black case front, catch plate engaged, parting line on the rounded corner, tools on a bench behind

Size checks specify points: three per outside dimension, three at the mouth, three at the floor. The ±1.5 mm cavity limit carries the draft allowance; squeeze it to ±0.8 mm and good lots come back. Latches take a 400 N pull, 0.5 mm alignment and a 0.3 mm hinge bore.

3. Pressure Decay, Drop and Vibration

Test pressure two hours after moulding, then charge to 5 kPa and hold 30 seconds; 0.2 kPa of decay passes. A warm case cools inside, pulls a vacuum and reads better than it is.

Test	Condition	Value	Pass line
Pressure	After 2 h soak	5 kPa, 30 s	0.2 kPa or less
Drop	Concrete, ten orientations	1.2 m	No crack, 0.3 kPa
Vibration	Random, three axes	1.04 g rms, 30 min	No loosening
Stack	Uniform lid load	250 kg, 24 h	Set 3 mm

Ten drops from 1.2 m onto 50 mm concrete, six faces, three edges, one corner, decay rechecked at 0.3 kPa; a case that stays intact but leaks is scrapped, since a distorted rim will not seal. Vibration is random at 1.04 g rms for 30 minutes per axis, clamped at the base corners.

4. Salt Spray, Cycle Life and Shielding

Salt spray on an Equipment Case means 5% sodium chloride at 35 °C for 48 hours: red rust fails, white rust fails above 5% of the area, and only metal parts are rated.

Equipment Case: a grey case open sixty degrees, insert split into three zones with a handheld meter, coiled cable and parts tray

Cycles run at 15 per minute and 23 °C, 5,000 for latches and 3,000 for hinges; at 30 per minute heat softens the catch and inflates the figure. Force may decay 20%, so 400 N ends at 320 N. Shielding is read at five points from 200 to 1000 MHz, where 45 dB and 35 dB are the usual limits.

5. Sampling, Documents and Batch Traceability

Sampling of an Equipment Case follows an adjusting plan: level II, normal, single, AQL 2.5 for class B and 4.0 for class C. A lot of 501 to 1200 gives code J, sample 80, accept 5, reject 6.

Lot	Sample	AQL 2.5 accept	reject	AQL 4.0 accept
91 to 150	20	1	2	2
151 to 500	50	3	4	5
501 to 1200	80	5	6	7

Documents ship as a set: certificate, per-unit record, batch certificate, packing list and instructions, each record carrying serial, inspector, date and instrument number. The eight-digit serial is stamped 0.3 mm deep at the lower right of the back panel; keep three samples per lot for 24 months, and trace no further than the material lot.

Conclusion

Class decides sampling, method and condition decide whether readings compare, the pass line decides scrap or release. Write instrument number, hold time and retention period into the clause, and the Equipment Case is accepted on evidence, not negotiation.

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.