A brand new 1,250 tonne Kobelco 16000 J-H crawler crane collapsed while undergoing final tests on July 26th at Kobelco’s plant in Takasago, Hyogo Prefecture, Japan.
The boom, jib and derrick mast collapsed sideways striking a number of buildings and vehicles in the vicinity. A man working in the immediate area, Tadashi Yamaguchi, 56, was declared dead at the scene, while Shihei Nishida, 23, secumbed to his injuries and died in hospital. A third man aged 59, remains seriously injured as does a fourth man. Others working in the area or the buildings affected received minor injuries.
From the photos and many videos posted locally, it looks like the derrick mast was ripped off its pivot pins, while the boom failed at the connection with the butt section.
Kobelco Construction Machinery has now issued a more detailed explanation of the incident which is published in full below:
"On July 26, an SL16000J-H crawler crane manufactured by Kobelco Construction Machinery Co., Ltd. was undergoing a load test prior to shipment.
The load test, where a suspended load is hoisted, was being conducted at Kobelco’s test yard, which is located within Kobe Steel’s Takasago Works* in Hyogo Prefecture in western Japan.
(*Note: Takasago Works is a manufacturing complex for Kobe Steel’s business divisions, covering steel and other metals as well as industrial machinery and equipment.)
When the crane was swinging during the test, for some reason, the boom and jib collapsed sideways, breaking the entire attachment.
The accident caused the death of two people and injured two others, a total of four. All four were doing other tasks when the attachment fell.
With a lifting capacity of 1,250 tonnes, the SL16000J-H is one of Japan’s largest lattice boom crawler cranes. The crane went on sale in Japan in May 2016. The cranes that have been delivered to customers have all passed the tests and are currently in operation.
Why the accident happened is unclear and the cause is currently under investigation. Kobelco is cooperating fully with the police and other authorities in the investigation in an effort to determine the cause."
Kobelco company officials also also issued the following statement: “We sincerely apologise for the loss of two precious lives (the two people from our subcontracting company), and deeply regret causing this serious accident,”
“We offer our deepest sympathy and condolences to the bereaved families of the two who passed away. In addition, we pray that the two injured workers will make a speedy recovery,”
The Kobelco 16000, which handles its 1,250 tonne maximum capacity at 10 metres, has been highly successful in Japan, with a good number of units already delivered since the first crane shipped in 2016. The units at work have completed some challenging and substantial projects with an excellent safety record.