Skip to content

Parted green pin plate lifting clamps

An incident occurred during the loading of a plate girder (weight approximately 12 tonnes) onto a cargo barge. As the girder was being lowered two out of the four certified Green Pin Plate Clamps, type 6.0 EH, parted causing the plate girder to drop onto the deck.

No-one was injured and no further damage was sustained at the time of the incident. However, since certified lifting gear parted during apparently normal operations, an investigation was carried out into the nature and cause of the fracture of the lifting clamps.

The investigation concluded that the basic cause of the fractured Green Pin Plate Clamp was a brittle fracture initiated by micro-cracks in combination with a fragile design.

The contractor involved proposes to initiate the following actions:

  1. Check the Safe Working Load for each single Green Pin Plate Clamp against the original certifications and Vendor’s documentation.
  2. Dismantle the Green Pin Plate Clamp and inspect the knife plate (= cam) for micro-cracks by using an adequate NDT method prior to using this kind of clamp for lifting plates, plate girders, etc.

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of all. The effectiveness of the IMCA Safety Flash system depends on Members sharing information and so avoiding repeat incidents. Please consider adding [email protected] to your internal distribution list for safety alerts or manually submitting information on incidents you consider may be relevant. All information is anonymised or sanitised, as appropriate.

IMCA’s store terms and conditions ( apply to all downloads from IMCA’s website, including this document.

IMCA makes every effort to ensure the accuracy and reliability of the data contained in the documents it publishes, but IMCA shall not be liable for any guidance and/or recommendation and/or statement herein contained. The information contained in this document does not fulfil or replace any individual’s or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.