D&D Stories
Stories from the elevator industry.
Buffer Replacement Records to Reduce Periodic Inspection Findings
Buffer replacement records must connect the model actually installed with the basis for its application and the work results. This article examines differences between PU Buffer and oil Buffer records, along with ways to organize certification histories and test documents.
2026-10-14
Review Points for Slim Type and Pencil Type Traction Machine Models at Modernization Sites
This article summarizes the sequence and checkpoints for narrowing down model names when reviewing Slim Type and Pencil Type Traction Machines at apartment elevator replacement sites.
2026-09-30
Bottom-type Overspeed Governors and MR&MRL Maintenance Access
Bottom-type Overspeed Governors and MR&MRL types differ in inspection position and work routes. The model name, stand, and rope path should be checked first.
2026-09-30
Why Check Sheave PCD Before Replacing Old Elevator Safety Parts
In replacement work for old elevators, sheave PCD is a key item to check because it determines the replacement scope for the Traction Machine and sheave, as well as rope suitability.
2026-09-24
Selecting an Overspeed Governor and Stand for Heavy Loads
This article explains why rated speed, rope routing, and stand installation conditions must be reviewed together when selecting an Overspeed Governor for a heavy-load elevator.
2026-09-08
Drop Test Data and Safety Gear Reliability
This article explains what test tower drop test data means for Safety Gear model certification preparation and on-site maintenance decisions.
2026-08-25
Inspection Points for Front-Rear Dual Encoder Signal Faults
This article outlines the rotation detection structure of front-rear dual encoder Traction Machines and the signs of signal faults that field maintenance technicians should check.
2026-08-11
UCMP Electronic Interlock Inspection and Car Door Opening Conditions
This article outlines the door-lock signals and inspection procedures that an Electronic Interlock must verify in the event of unintended car movement.
2026-07-29
Diagnosing Wire Rope Wear Patterns on Double Wrap Sheaves
This article examines how rope and sheave wear relates to noise and vibration in Double Wrap systems and outlines an inspection sequence for identifying tension imbalance.
2026-07-21
Oil Buffer Replacement: Check Stroke Before Leakage
Oil buffer inspection does not end with checking for leakage. The available stroke, return condition, and installation verticality must also be checked together.
2026-07-09
Managing Certificates and AS Manuals for Gyeonggi Inspections
This article explains how to manage elevator certificates, technical documents, standard prices, and AS Manuals so they can be checked immediately on site in preparation for local government inspections.
2026-07-09
Safety Parts for Elevators Over 21 Years: Replacement Planning
This article outlines how discussions on stricter replacement deadlines for safety parts in ageing elevators affect maintenance budgets, inspection preparation, and document management.
2026-07-07
Elevator Safety Gear: Function and Inspection Points
This article outlines the operating principle, periodic inspection, wear and corrosion checks, and replacement criteria for elevator Safety Gear.
2026-07-06