How to Reduce QC Inspectors with Automatic Sorting Machines: Is It Worth It?

✨How to Reduce QC Inspectors with Automatic Sorting Machines: Is It Worth It?✨

Factories producing high volumes of parts (screws, nuts, bolts, rivets, springs, O-rings or plastic parts) often need many QC inspectors to remove NG parts before shipping.

The larger the volume, the bigger the problems.

This article explains how to reduce inspectors with automatic sorting machines and which option fits your factory.

■ Why manual inspection is not enough

Fatigue: human eyes are excellent, but after hours of repetitive checking, concentration drops and NG parts slip through.
Inconsistent results: each inspector judges differently, especially borderline defects.
Many people needed: for low-cost, high-volume parts, inspection labour can cost more than the part itself.
Sampling only: calipers and profile projectors cannot keep up with production, so only samples are checked, not 100%.

■ How an automatic sorting machine (AOI) works

A vision sorting machine, or AOI (Automatic Optical Inspection), photographs every part from several angles with multiple CCD cameras.

Image-processing software measures dimensions and finds defects, rejects NG parts and counts OK parts automatically.

It checks:

Dimensions: length, diameter, thickness, thread pitch
Deformation: bent, twisted, dented
Mixed part numbers of similar size
Surface defects: scratches, dents, stains, foreign matter, cracks, chips, burrs

Speed depends on the model and part shape.

Glass-table machines sort about 300–800 parts per minute, and a special system for M3–M5 screws reaches 2,000 parts per minute.

For defects a camera cannot see, such as abnormal hardness or wrong material, it can be combined with an eddy current tester.

■ Two ways to reduce inspectors

Q. Option 1: Buy an automatic sorting machine

A. Best for factories with parts to inspect every month.

You control quality in-house, and inspectors can move to other work.

Nano Seimitsu is the distributor of VIZION, UAZNC, DECSYS and CCM sorting machines in Thailand and can test your real parts before you decide.

See automatic sorting & AOI inspection machines.

Q. Option 2: Use a parts sorting and inspection service

A. Best for irregular work, urgent problem lots, or factories not ready to invest.

Send your parts to Nano Seimitsu for 100% automatic inspection: 50,000–100,000 parts per day, about 0.07–0.20 THB per part depending on difficulty, or about 6,000 THB per 8-hour day.

See parts sorting & 100% inspection service.

■ A simple way to judge the cost

Count the inspectors and monthly labour cost spent on this work.
Estimate the cost when NG parts reach your customer: claims, re-sorting, transport and lost trust.
Compare with the sorting service price per part, or the machine price divided by its months of use.

Many factories start with the sorting service to prove the machine can detect their defects, then buy a machine once volumes are stable.