1. Service Quality Presentation
Godwin Chidiebere Nwafor
Port Harcourt, NGA

2. SchlumbergerPrivate
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Outline
• Introduction
• Sequence of Events
• Summary of the Events
• Remedial Actions
• Focus of Investigation
• Action Plan
• Corrective Action Plan
• Plots/Charts & Pictures
• Client’s Opinion

3. SchlumbergerPrivate
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Introduction
Customer: Sterling Energy
Exploration &
Production Company
SLB Supervisor: Godwin Nwafor
Treatment #: 983738 Has FSM been contacted? Yes
Equipment #
involved in incident:
Cementing silos Has FQC/HSE been
contacted?
No
Job or Type of
Activity:
9 5/8” production
casing
If you have entered a RIR,
please give Quest #
20130611132500
Location: Anieze 9 Date of incident: 10th
June, 2013
Time of incident: 12:10 pm 3rd
Party Name if applicable: NA
Customer Contact
Field:
Anieze Customer phone number: +234-8152092254

4. SchlumbergerPrivate
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Sequence of Events
4:00 am – Arrived rig site to prepare for the up coming job with
the cementing crew. Started mixing chemicals in the pits
already prepared earlier.
7:17 am – Carried out STEM 1 on all equipment on location.
Primed the cementing unit using water
9:00am – Conducted safety meeting with all going to be
involved during the job on the rig floor.
9:27 am – Flushed cementing lines before conducting the
pressure test
9:32 am – Tested cementing surface lines to 4000 psi

5. SchlumbergerPrivate
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Sequence of Events
9:55 am – Rig pumped 20 bbls of base oil and
10:00 am – Rig pumped 50 bbls of Scavenger mud
10:19 am – Dowell pumped 30 bbls of chemical wash from
cementing unit
10:29 am – Rig pumped 62 bbls of MUDPUSH II spacer
10:47 am – Bottom plug was released from cement head on rig
floor
10:54 am – 12:05 pm – Started mixing lead slurry at 12.5 ppg

6. SchlumbergerPrivate
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Sequence of Events
 Mixed slurry in the mix tub to the required density
 Mud engineer took sample from sampling point to ascertain
density
 Company representative confirmed density and gave go
ahead to start pumping.
 Pumped a total of 355.4 bbls of lead slurry
12:05 pm – 12:10 pm – Started mixing tail slurry at density 16.4
ppg. Confirmed tail density with company representative and
continued pumping downhole

7. SchlumbergerPrivate
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Sequence of Events
12:50 pm – observed difficulty in maintaining required tail
density,
 Signalled to bulk operator to check supply of cement.
 Stopped pumping to troubleshoot and find root cause of poor
cement supply.
 The silos were checked to confirm discharge supply
 Confirmed silos were empty without cement

8. SchlumbergerPrivate
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Sequence of Events
1:10pm – The situation on the rig was communicated with
SEEPCO office in town and the decision to drop the top plug
and displace was taken.
 Pumped the remaining slurry in the mixing tub. Total tail
slurry volume pumped was 84.6 bbls
 Climbed up to the rig floor to release top plug from cement
head
 Pumped 5 bbls of Water to flush cement off the lines

9. SchlumbergerPrivate
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Sequence of Events
1:18pm – 2:48 pm – Rig took over displacement, pumping
SOBM
 Pumped a total of 538.7 bbls
 Bumped plugs with 1604 psi
 Casing was tested to 3500 psi for 10 minutes using
cementing unit
 Pressure bled off after successful pressure test.
3:00 pm – Did a thorough and proper wash up of cementing unit
to ensure all lines were clean.

10. SchlumbergerPrivate
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Summary of the Events
While pumping the tail slurry during the 9 5/8” casing cement
job on Anieze 9, the cementer observed he was unable to
maintain the required designed density of 16.4 ppg for the tail
slurry. After several attempts to increase the density, and
after beckoning to his bulk plant operator, he observed there
was no more cement in the silos to feed the surge can. At
this point, the client asked him to pump the slurry left in his
mix tub downhole. The total volume of tail slurry pumped was
84.6bbls.

11. SchlumbergerPrivate
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Summary of the Events
The top plug was then dropped by the cementing crew and
then displacement commenced. 5 bbls of water was pumped
from the cementing unit after which the rig took over and
continued with the displacement. The plugs were bumped
with 1604 psi after which the casing was tested to 3500 psi
for 10 minutes. The pressure was then bled off after a
successful pressure test.

12. SchlumbergerPrivate
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13. SchlumbergerPrivate
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Remedial Actions
Time was taken to check the silos to confirm if they were empty.
Checked all discharge lines to confirm no blockage or
restriction along the lines. A crew was mobilized to the
location to maintain the silos in preparation for the next job.

14. SchlumbergerPrivate
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Focus of Investigation
• Discharge problems from the silos due to blockage or
restrictions.
• Inadequate cement on location due to improper inventory
management prior to cementing job
• Shortage of cement supplied to the rig during last bulk
transfer.
• Poor fluffing of cement prior to the job
• Emergency Security Evacuation of Personnel from the Rig
and Rushing for the job
• Poor maintenance of Silo and leftover of handgloves inside
the Silo that blocked the discharge line

15. SchlumbergerPrivate
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Action Plan - Immediate
• Attempted severally to aerate the silos and totally discharge
any left over cement within silos.
• Opened the silo hatches to see inside the silos and confirm
exact picture.
• Mobilized cementing crew to carry out thorough
maintenance on the silos.

16. SchlumbergerPrivate
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Corrective Action Plan
• Plan to have extra cement onsite
• Proper inspection of all silos prior to offloading cement
• Proper inventory tracking for both chemical and cement on
site

17. SchlumbergerPrivate
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Plots/Charts

18. SchlumbergerPrivate
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Pictures
Pictures of Cement Silos when opened after the Job

19. SchlumbergerPrivate
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Pictures
Closer view of opened hatch showing some cement left inside

20. SchlumbergerPrivate
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Pictures