EMSD releases investigation report on Ngong Ping 360 cable car incident

Having completed a comprehensive investigation into the Ngong Ping 360 cable car incident on January 25, the Electrical and Mechanical Services Department (EMSD) released its investigation report today (April 3). As the required improvement measures have been implemented satisfactorily, the EMSD has agreed that cable car operation may resume.

The EMSD completed the investigation with assistance from an independent expert. The report pointed out that the accident was due to the irregular spalling in the inner race of the bearing of bull wheel no. 4 of the cable car system and the uneven wearing out of the linings of that bull wheel. This caused vibration of the haul rope which in turn triggered the position sensor of the bull wheel to stop the cable car's operation. Examination of the lubricating grease collected from the bull wheel bearing revealed that water was present in relatively large quantities in the grease, which reduced the effectiveness of lubrication and caused spalling of the bearing.

To prevent recurrence of similar incidents, the report pointed out that Ngong Ping 360 Limited (Ngong Ping 360) shall implement the following improvement measures before re-opening the cable car:

‧ Replace all bull wheel bearings;
‧ Enhance the vibration monitoring system of all bull wheel bearings to capture data on an ongoing basis, and increase the frequency of examination of the collected data to once every two weeks;
‧ Conduct monthly grease analyses to monitor the moisture and metal contents of the lubricating grease and step up the re-greasing frequency according to the result;
‧ Store and handle lubricating grease properly to prevent ingress of moisture;
‧ Check and re-grease all bearings of the ropeway system;
‧ Tighten the procedure for inspection and replacement of the bull wheel linings;
‧ Conduct a comprehensive review of the maintenance regime of the cable car system and complete the action items identified;
‧ Enhance the emergency handling procedures, and provide staff with regular training to ensure their quick and appropriate response to unforeseen incidents; and
‧ Carry out an annual examination of the cable car system to ensure a satisfactory result.

The EMSD has conducted on-site examinations of all the improvement measures. It confirmed that the required measures have been implemented satisfactorily and can effectively prevent recurrence of similar incidents and enhance system reliability. Therefore, the EMSD has agreed that Ngong Ping 360 may resume cable car operation.

A spokesman of the EMSD said, "Ngong Ping 360 must learn from the incident. It has implemented all the improvement measures. Ngong Ping 360 must also step up efforts to manage the ropeway and ensure that the improved maintenance procedures of the ropeway, emergency handling procedures and reporting mechanisms are strictly and consistently followed. The EMSD will continue to closely monitor the operation and maintenance of the cable car system to ensure the safe operation of the ropeway."

The report can be downloaded from the EMSD's website: www.emsd.gov.hk/emsd/e_download/pps/ar/English_version_Incident_2012-01-25.pdf .

Ends/Tuesday, April 3, 2012
Issued at HKT 13:01