An independent laboratory analysis of after-market escalator chain (claimed to be the replacement for KONE’s US67884 escalator chain) yields startling results, and causes us grave concern. Here’s why:
This after-market chain does not comply with ANSI Safety Code standards.
The unretouched photo above shows the results from a critical breaking load test performed on a five-link strand of after-market chain claimed to be rated at 41,000 lb. Test results show the after-market chain failed at just 35,000 lb. load. The after-market chain failed the code-required load and factor of safety as defined in ANSI A17.1-2013, Rule 188.8.131.52.2.
After-Market Chain can Permanently Damage other Critical Escalator Components
Compare these results:
Outer and inner diameters of after-market protection rollers often have a very poor finish (not ground). This condition, combined with excessive hardness that is significantly harder than defined by KONE specifications, can lead to accelerated wear of the bull gears, lower reversing station sprockets and load support curves (novatex boards). The increased internal friction causes rollers to slide instead of roll.
The after-market chain that claimed to be the “equal” of KONE (Montgomery) US67884 and US67883 chain is nowhere close in terms of design, manufacturing quality and code-compliance.
After-market chains are often laser cut (photo on left). KONE chain components are machine-stamped as shown in the photo on the right. Hard-tooled products are more precise.
Outer link plates of after-market chain have deep, uneven grooves from laser cutting. The accumulation of imprecise manufacturing tolerances leads to assembled chain that exhibits skewed orientation when put under a normal operating load. This generates uneven and excessive wear of all operating components in the escalator step band. This begins the moment the after-market chain is installed. Also note the round holes in the after-market chain are not formed with the anti-rotation feature (flats) that is used in KONE chain to prevent rotation of similarly-machined step pins.
Contact surface between outer link plate and the retainer clip on the after-market chain is significantly reduced by the fit between the pin and outer side plate — as much as 15% of the contact area missing (see arrows). This weakens the chain in terms of reduced press-fits and can lead to instabilities (e.g. skewed chain strands) – as reflected in the photos below, showing the skewed relationship of both ends of a chain strand under load.
After-Market Chain Under Load
The right photo illustrates “skewing” of the after-market step chain extended pins when load is applied. In this test, one end of after-market chain is rigidly mounted and load is applied through a swivel. The surface hardness of pins in after-market step chain is found to be hardened to a depth twice that defined by industry standards. This condition can result in very brittle chain pins.
Seriously. Why buy after-market products especially when KONE Spares offers superior OEM products at essentially the same price?
The so-called “bargain” of after-market parts is really no bargain at all.