Page 10 - Flip IOCL Book.cdr

Case 6 Date: 28.12.2018 Time: 11:00 hrs.

Incident

Benzene loading bay no. 2 Benzene Tanker no. UP15DT4033 was fully loaded with 25410 Kgs of Benzene.
During disconnection of the loading arm Benzene started leaking from the tanker flange (manifold valves).
It was observed that Benzene was coming out from the manifold flange even after all the manifold valves
were found in fully closed condition. Immediately master valve was closed but leakage of benzene
continued due to passing of manifold valves & master valve. Finally leakage was arrested by removing
loading arm and putting end blind & situation brought under control.

Root Cause

1. Inefficient tankers checking system.
2. Passing isolation valves (Manifold and master).
3. Passing of the compartments.
4. No view glass to check complete draining.
Isolation valve in close loop
draining system

Tanker Valve manifold

Close loop draining
system to Close
blowdown vessel

Actual Site Photo of Draining assembly for Benzene Tanker

Recommendations

1. Tanker's overall checking system should be strengthened to ensure thorough healthiness of the tankers
before sending the tankers for loading at Gantry.

2. Marketing to ensure complete inspection of Master valves & Manifold valves by water filling / Hydro
test or by some other means and ensure NIL passing of i/vs before issuing Green cards for the tankers.

3. Passing of the compartments shall be checked at some fixed intervals and same shall be recorded and
shared with Gantry operation.

4. View glass shall be provided in the draining hose assembly to ensure completeness of the residual liquid
draining from the loading arm.

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