Cycle Time Analysis: Find the Bottleneck Station
The Line That Ran Fast Everywhere Except One Place A customer wanted to increase a packaging line’s output from 60 to 90 parts per minute. They sped up the infeed conveyor, the labeling station, and…
Author: JUMI
Pre-Use Safety Inspection: 5-Minute Start-Up Check
The Start-Up That Skipped the Inspection A line was restarted after a weekend shutdown. The operator pressed “auto” and walked away. Within 30 seconds, a robot collided with a fixture — the fixture had been…
Safety Signage: Signal Words, Pictograms, and Placement
The Warning Label That Said Nothing A robot cell had a warning sign on the fence. It read: “Warning: Robot. Authorized Personnel Only.” The sign was black and yellow, faded, mounted 2 meters up on…
Electrical Isolation: Live-Dead-Live Test and Capacitors
The Voltage That Was Still There A technician opened a motor starter to replace a contactor. He turned off the local disconnect switch (a rotary handle on the cabinet). He tested the line side with…
Pneumatic Energy Isolation: Vent, Verify, Lockable Valve
The Cylinder That Moved After the Air Was “Off” A maintenance technician was replacing a seal on a pneumatic cylinder. The supervisor closed the ball valve on the air supply. The technician crawled into the…
Rotating Part Guarding: Nip Points and Coupling Covers
The Shaft That Ate the Glove A line shaft on a conveyor was exposed — a 50 mm diameter steel shaft turning at 120 rpm, with no coupling guard. An operator’s glove brushed it. The…
Noise Exposure and Hearing Protection: Source Before PPE
The Operator Who Lost His Hearing on the Press A punch press operator worked at a stamping plant for 15 years. He wore earplugs (sometimes). At his annual hearing test, he had 40 dB of…
Risk Assessment ISO 12100: Hierarchy of Controls
The Machine That Passed Inspection and Still Hurt Someone A new packaging cell was delivered, installed, and inspected. The inspector checked the guards, the e-stop, and the light curtain. All present. The machine ran. Three…
Machine Guarding: Fixed vs Interlocked Guards and Bypass
The Guard That Was Bolted Shut — and Then Removed A conveyor had a fixed guard over a nip point between the drive pulley and the belt. It was bolted in place. The maintenance crew…
Emergency Stop Circuit: Hardwired Safety Relay, Not PLC
The E-Stop That Did Not Stop the Machine A packaging line had a red mushroom button on the control panel. The operator hit it during a jam — the line kept running. The electrician opened…
Lockout Tagout LOTO: Six Steps and Stored Energy
The Press That Cycled While Someone Was Inside A maintenance technician reached inside a stamping press to clear a jam. His partner was supposed to hold the e-stop button. The partner got distracted, released the…
PLC Program Backup and Recovery: Version Control and Battery
The Day the PLC Lost Its Mind A PLC on a packaging line died — the CPU faulted, the battery alarm went off, and the program vanished. The maintenance technician plugged in his laptop, opened…
Air Leak Detection: Ultrasonic Survey and Compressor Savings
The Plant That Was Paying for Air Nobody Used A food plant had a 30 kW air compressor that ran almost constantly. The production manager said, “We need another compressor — demand is growing.” We…
Vibration Analysis: Predictive Maintenance with a Handheld Meter
The Fan That Shook for Six Months Before It Stopped A large exhaust fan ran in a paint booth. Maintenance heard a new rumble about six months before it failed. They turned the volume up…
SMED Changeover: Internal vs External and Quick Clamps
The 4-Hour Changeover That Took 20 Minutes A customer ran a stamping press that made 12 different part numbers. Every changeover took four hours — the die was unbolted, lifted out, the new die lifted…
