Figure 1: Accident involving Piling Barge and Transportation Barge
Figure 2: Sketching drawing before accident
Figure 3: Sketching drawing after accident
An accident occured on Jun 2011 involving a self-propelled piling barge at a private jetty located in Port Klang,Selangor. The accident caused serious injury to one worker who later died at the hospital while another three workers were treated with minor injuries. Those workers were working or on the top deck of the self-propelled transportation barge which was docked in front of the piling barge.
The piling barge which was sent back from the piling work in Malacca had undergone maintenance and servicing on the hydraulic cylinders for the luffing winches [on the port and starboard sides]. On completion of the work,the workers were instructed to carry out functional testing on the luffing winches for the luffing mast frame.The luffing mast structure was connected by pendant roping to the A-frame structure which has a tall vertical piling leader attached at its end.
According to the workers the test had been conducted for 4 times.In the midst of the testing one of the luffing winch drums [on the starboard side] suddenly failed and the wire rope layers on the drum uncoiled until its terminal connection.The terminal connection broke off completely from the cap-screw joints which was on the inside of the drum. The failure of the starboard luffing drum mechanism ultimately led to the complete collapse of the luffing mast frame, A-frame structure and the piling leader.During the incident the transporation barge which was docked in front was hit when the structures fell on its top deck.
Investigations found that there were severe damages on the main structure of the luffing winch, luffing mast frame, A-frame and piling leader. Also, the starboard luffing winch rope measuring 38 mm in diameter had completely unwound from the drum and had broken in about three places throughout its length.
The synchronous luffing winch system for the piling barge uses one length of wirerope and the wirerope terminates on the winches. Each of the winch system uses two hydraulic cylinders to control the braking system.
Recommended Control Measure
- The owner or occupier of the piling barge must ensure that Safe Operating Procedures [SOP] for the maintenance works and functional testing on the piling barge were prepared, documented and explained clearly to the workers.
- Secure safely all tall moving parts of the piling barge that have high centre of gravity to avoid any mishap during the maintenance work.
- Permit-To-Work (PTW) must be prepared, issued and followed before commencing any maintenance work on the piling barge. The PTW must include Hazard Indentification, Risk Analysis and Risk Control [HIRARC] or Job Safety Analysis [JSA] on the specific job to be performed. The PTW must ensure so far as practicable, the safety, health and welfare of the workers, public and those who may affected by the job.
- All the inspection, adjustment, repair and maintenance works on the piling barge mechanism should be carried out under the supervision of a competent person. The workers who are undertaking such work need to be trained and have relevant experience and skills to carry out such work safely.
- Any repair or maintenance work on the piling barge should follow published International Code Of Practices or Guidelines.
- Testing of the piling barge structures and mechanism shall not be conducted in poor weather conditions.
- The owner of the jetty shall have control of the works undertaken in his area to ensure that the place of works are safe and without risk to health.
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