What is Quality Inspection?

An inspection is an activity such as measuring, examining, testing or gauging one or more characteristics of a product and comparing the results with specified requirements in order to establish whether conformity is achieved for each characteristic. (This definition comes from the ISO 2859 standard, which is derived from MIL-STD 105 E.)

Generally, quality inspectors do this by following a pre-established Check List based on certain product specifications. In fact, any type of product can be inspected, starting with just the components used for the product to semi-finished ones and (most often) the finished product itself.

Inspected products can be the components used for production, semi-finished goods, or (most often) finished goods before shipment to a customer.

In Quality Inspection inspectors should inspect the  items with the following categories:

A. Quantity (Production Status of finished, packaged and unpackaged items)
B. Workmanship (Defects if available)
C. On-Site Tests (Product Function and Barcode Scan Tests)
D. Materials & Components (Dimensions, weight, color, general appearance)
E. Packing and Packaging (Dimensions of export cartons, product box)
F. Marking & Labeling
G. Photos and videos and Client Special Requirements

Part of the job is to pick samples and think;
“Would a consumer/user accept this?” if it is sold to users,
“Would this create issues down the road?” if the part is to be further processed or assembled. However, there needs to be a checklist too.

After all, the products were made based on agreed-on specifications? Does production conform to these specs? The typical approach is to use these specs as a checklist, to guide the control process.
Sample checklist for a wristwatch;
Check PointDescription
Watch CaseCheck for scratches, bad polishing, other cosmetic defects
Watch StrapCheck for scratches, bad prints, other cosmetic defects
Gift BoxCheck for scratches, bad prints, other cosmetic defects
Watch FaceThe clock shall be shiny, not matt
LogoCross-check clients artwork to ensure logo is an exact match
Net WeightTake weight, report actual findings and compare to client specification. Values in grams
Watch DimentionsTake dimensions to report actual findings and compare to client specification. Values in mm.
Giftbox DimentionsTake dimensions to report actual findings and compare to client specification. Values in mm.
Smell CheckNo strong or irritate smell is allowed on the product.
MovementCheck movement model against client specs. Eg. Seiko AL35
Drop TestDrop height should be 1m on flat and hard surface with batteries inside. 6 Flat drop ( bottom, top, right, left, front, back) on each sample. The product should work normally 1 hr after test.
Movement TestRemove the plastic movement blocker to test the movement for 3 hours.
Component CheckOpen the watch case to check the movement and battery.
Glass HardnessCheck the glass hardness with the specific hardness testing tool.
Scrach surface of StrapScratch the surface of the print to see the if colors come off
Assemble Fitness CheckIt is important that the strap is securely fitted and correctly assembled.
Basic FuntionCheck the basic function of the product. It should work as claimed.
Full FunctionCheck the full functions as claimed in the user manual.
Fatigue TestPress, push, use adjustable parts 50 times. The product should be as remain the same as new.
Color FastnessRub 30 cycles with dry cotton cloth and 10 cycles with wet cotton cloth.
Adhesive testUse 3M tape for testing coating, electroplate and markings (logos, labels, barcodes…)
Fitting TestWear the product, it should fit well and no obvious problem.
Strap StrenghtPull the strap with normal strenght of around 3lb, belt should remain firmly.
Water PressureUse water pressure machine to check model A: Gold (should strain 3 ATM) – (Depends on specs. and design)
Time accuracyCheck for the time accuracy for 1 day, record actual finding.
Shaking testShake the product 3 minutes, product should remain same after the test.
Watch hand alignmentCheck watch if hand align
Internal workmanshipOpen the unit, check the internal workmanship: such as right polarity connections, no exposed connector, good connections, cables are well fixed etc.
Quality inspection is an essential part of every production line. It might seem like an unnecessary investment at the start,
however, with proper management, they can reduce future costs, relating to customer support, warranty returns, and rejected/returned items. They can even add value to your company, as you’ll count on a competitive defense tool that will eventually pour more money into your pockets.