Chain Hoist Failure on MPD Flow Line
Chain Hoist Failure
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BOP and Riser running operations completed after an extensive repairs and maintenance
period while the BOP was on surface.
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Managed Pressure Drilling (MPD) choke and lines had to be rigged up: two 3rd Party
Contractor personnel & one Company personnel.
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Section of pipe (3.2mx320kg) required to be installed on the lower platform of the BOP
transporter. A 1T chain fall was added to provide additional reach
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PTW & JSA in place; however, Area Supervisor did not review the PTW and JSA correctly.
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Agreed amongst the team that the Contractor supervisor would operate the auxiliary hoist
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Hook not directly above the load; intention to man-handle the pipe clear of obstructions, no
consideration for tag lines.
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During the lift the pipe was seen to get caught under the flange. Both personnel made
attempts to stop
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Operator did not respond and continued to hoist the load, the upper chain hoist hook
stretched beyond its elastic limit, reached its yield point, and the load dropped
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Chain Hoist Failure
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The entire assembly with rigging fell to the deck, part of the rigging struck the IP’s hard hat
and knocked it off his head. The IP sustained a superficial 1.5cm laceration to his forehead as
a result.
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DROPS calculator indicates Probable Fatality for the 7kg chain hoist.
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Chain Hoist Failure
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Chain Hoist Failure
Summary:
Critical Factors
Inadequate control of lift allowed the load to be caught under the overboard valve flange
resulting in overload and failure of the chain hoist
Improper positioning of people allowed IP to be in an unsafe position.
Immediate/System Causes
Inadequate control of 3rd Party Contractor
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Bridge crane operated by 3rd Party Contractor contrary to Company Policy
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Company AD allowed this to happen
Poor leadership by Area Authority
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Task not fully understood; worksite and controls not audited before
endorsing the PTW & JSA
Inadequate implementation of PNA safety processes by the team
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JSA completed but not appropriate for the task. The supporting T5 risk
assessment process not followed and therefore appropriate controls not
identified and implemented.
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No lifting plan, no tag lines, hands on load where not required, no
additional supervision, positions of people, no dedicated banksman.
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Chain Hoist Failure
• Safety Stand Downs to be performed by Company Management; application of HSE policy in
relation to the incident to be a primary focus.
• Post lists of trained and approved operators of mechanised handling equipment
• 3rd Party Contractors to take immediate CoW refresher training & 3 monthly thereafter.
• Develop specific JSA for MPD rig up and rig down
• Amend Job Descriptions to include clear expectations of an Area Supervisor within the roles
and responsibilities, to be reviewed with the OIM and countersign.
• Area Supervisor will cascade the HSE Policy presentation to his team including 3-5 of his
personal expectations.
• Review effectiveness & implementation of the following and amend as necessary:
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3rd Party Inductions & 3rd Party Management
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Lift Planning & Lifting Guidelines
• Better planning of work
• Update PTW manual to include the requirement for periodic site visits by Area Supervisors.
Record of PTW signatories will be updated to ensure the requirement is effectively
communicated.
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DROPS HiPo
Summary
Whilst running in the hole with 5 1/2” drill pipe, a service loop retainer bar on
the vertical traverse arm of the Upper Bridge Racking Crane fell to the rig floor.
The retainer bar broke free from its mounting on the upper bridge racking crane,
when it contacted a stand of drill pipe that was racked back in the forward
setback area.
Background
Whilst making a connection at the rotary table an alarm tripped within the Zone
Management System due to equipment proximity & collision risk.
In order to clear this the Pipe Handling Operator utilised a “Manual Mode” which
allowed a greater range of operational envelope for the Vertical Pipe Handler
and an increased risk of collision with the setback.
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DROPS HiPo
During the installation and commissioning
of the VPH the BRC service loop was
identified as a possible snagging point on
the Top Drive. Concerns were raised and
consideration given to a modification,
possibly a drag chain.
The drag chain required engineering and
support from specialist contractor thus was
not an instant fix; an interim solution
utilised by Company on two other similar
systems in its fleet was therefore installed;
this was retro fitted retention loop.
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DROPS HiPo
As a temporary measure a retaining bar was
fitted. The material utilised was 16mm stub
bar approximately 430mm in length and
formed into the required shape. It was
covered with heavy duty wire spiral in order
to prevent chaffing of the loops on the
thread.
There is/was no Management of Change
(MOC), or Request for Engineering Support
(RES) in place for this modification.
The positioning of the retaining bar is
indicated top right, the bar following the
DROPS bottom right.
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DROPS HiPo
Whilst working to overcome the
Zone Management System
alarm the VPH was operated in
manual mode and came into
very close proximity to the
setback, as depicted in the
photograph.
The retainer bar struck against
the setback and subsequently
fell as a result of the contact.
The PHO was aware of the
proximity and stated that he did
see a slight contact with the
service loop and setback.
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DROPS HiPo
A person crossing the aft
drillfloor from the
doghouse heard the
retaining bar fall and
investigated.
He was approximately
3m away at the time of
impact.
DROPS calculator
indicates a FATAL
outcome had he been
struck.
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X
Possible Immediate Causes
Actions
3 Use of protective equipment or methods
3.5 Disabled guards, warning systems or safety devices
The use of Manual whilst it is a required operating mode, effectively removes
certain parameters from the system thus allowing a greater range of movement
and the possibility for collision into the setback.
Conditions
4 Lack of focus or inattention
4.6 Routine activity without thought
Manual mode is utilised frequently without any real consideration given to the
hazards that are inherent in its use, particularly whilst operating in proximity to
the setback.
5 Protective systems
5.1 Guards or protective devices not effective
The design of the retaining bar was woefully inadequate as a working solution. A
sturdier, better engineered, & none threaded bar should have been fitted.
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Possible System Causes
Personal factors
13 Behaviour
13.1 Antecedent not present
No prompt present in the PHO cabin in the form of a placard/sign as a reminder
that Manual mode requires extra care and attention when in use.
13.2 Antecedent not effective
Previous training regards certain limitations of the system being removed in
Manual mode, plus his seeing the VPH in close proximity to the stands were not
enough to cause him to stop and rethink the operation.
Job factors
15 Training/Knowledge Transfer
15.3 Knowledge Transfer Not Effective
A well established OEM course was delivered, the practical aspect reiterating the
requirement to pay extra care and attention in manual mode. This however was
not effective in this case at driving home the importance of paying attention
whilst in Manual/Direct Mode.
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Possible System Causes (continued)
Conditions
16 Management/supervision/employee leadership
16.10 Risk analysis not effective
A lack of understanding by senior personnel with regard the potential hazards
inherent whilst operating in Manual mode.
18 Engineering/design
18.1 Technical design not correct
The design of the retaining bar was woefully inadequate as a working solution. A
sturdier, better engineered, & none threaded bar should have been fitted. The design
should have been appropriately reviewed by several personnel and approved through
the proper channels utilising management of change.
18.5 Assessment of Operational Effectiveness not Effective
Retainer bar installation occurred after VPH commissioned with no revalidation of
acceptance.
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Possible System Causes (continued)
19 Control of Work (CoW)
19.2 Risk assessment not effective
A general lack of understanding with regard the potential hazards inherent whilst
operating in Manual mode was apparent; no mention of hazards related were present
on the JSA.
22 Standards/Practices/Procedures (SPP)
22.2 Development of SPP not effective
Procedure for tripping with the VPH made no mention of Manual Mode, therefore
any review and subsequent JSA would not incorporate the hazards associated as a
result.
23 Communication
23.2 Vertical communication between Supervisor and Person not effective
Communication between the Driller and PHO did exist but was not effective via the
talk-back system. The driller had to resort to using the telephone in order to
effectively communicate.
23.4 Communication between work groups not effective
Final installation of the retaining bar was not properly communicated between the
project and operation team; the operation team had little input into the design and
were not provided with any follow up information following the installation.
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Action Items
Operating Procedure (s) to be updated
JSA to be developed regarding VPH Operating Modes
JSA to be updated to include hazards related to utilising Manual/Direct mode.
Develop, install, & commission permanent retaining method for service loop
Implement interim inspection plan to reduce potential damage service loop
Installation of Rig Floor Color Coding of Hazardous Areas
Evaluate Enhanced Communication Capabilities between Driller & PHO
Complete installation of lights/alarms on Lower Guide Arm on rig floor
Hazard ID training (with specific focus on VPH)
Contractor Operator Training to be reviewed
Evaluate/implement method to reduce use of Manual Mode
Any after market/non-OEM modifications subject to rigorous MOC and
testing/acceptance
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