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5.24 PUMPROOM INSPECTIONS

An accurate log must be maintained of the pumproom operations, including the starting and stopping time(s) of each pump and the reason for the change. When each pump is started, it should be immediately inspected for proper operations.
The inspection should include a visual check of the pump drive shaft bulkhead seal, the driveshaft coupling, the forward and aft pump glands, local readings of the pressure and RPM instruments (as compared to the CCR readings).
If the pump is equipped with bearing, seal and/or casing temperature probes, the local readings of these should be checked. If no temperature sensors are fitted, the temperatures must be checked by hand. This can only be done safely if the parts to be checked are safely guarded from rotating parts. No part of the pump should be too hot to touch with a bare hand: 60 C (140 F), unless the cargo is heated to a higher temperature.

5.24.1 Pumproom ventilation
The pumproom ventilation should have been in operation continuously since before arrival at the discharging berth. Continuous ventilation is essential to maintaining a safe atmosphere at the bottom levels of the pumproom.
All personnel assigned to conduct pumproom inspections have two principal obligations:
To advise the cargo watch officer before entering the pumproom to make an inspection, when reaching the bottom of the pumproom and when the inspection is complete.
To verify that the pumproom ventilation is functioning properly before descending below the top level of the pumproom.

The cargo officer should have a member of the deck watch stand by at the top or some intermediate level of the pumproom to keep watch over the person inspecting the lower level equipment. The crew member keeping watch must have a portable radio and understand that his first duty if the other person is overcome is to raise the alarm and then ascend to the top of the pumproom to assist or become part of the rescue team. He must not descend to the lower level to rescue his shipmate. If the pumproom is under continuous ventilation there is adequate time for a rescue to be organised (see section 2.15.8).
Pumproom rescue equipment must be immediately available in the pumproom during cargo discharge.

5.24.2 Checking sea valves


Case study
Four days after Trieste harbour had suffered a major crude oil spill, a 125,000 DWT tanker began discharging crude oil. At 1815, oil was discovered along the vessel's port side. An investigation of the situation in the pumproom disclosed that the port side sea chest was fitted with two butterfly valves, both of which were apparently leaking. The outer valve was replaced. Local authorities demanded a class inspection of the sea valves. The starboard sea chest was also dismantled and checked. The vessel was arrested by authorities to ensure clean up costs would be paid and owners were required to post a bank guarantee of USD 250,000 to obtain its release. Clean up costs totalled USD 207,000 when complete.

Case analysis
This problem is largely caused by owner's selection of a valve specification which was not appropriate for the critical function performed by the pumproom sea chest. Having selected a less than optimal design, owner's should have put in place a programme for regularly verifying the integrity of the sea valves. (See section 2.18.1) Apparently this was not done by owners, or by the master or chief officer on their own initiative. The outcome of this management decision cost considerably more than the installation of a more secure valve type!



A drain and sensor installation to prevent pollution when pumproom valves leak.

One of the most common causes of harbour pollution by tankers is leakage through sea valves. This is normally not a problem with SBT ships, but is still a potential source of trouble for CBT vessels. Many vessels are now fitted with butterfly valves on sea chests. Butterfly valves offer a lower reliability for tightness than the previously used gate valves. To minimise the potential for escape of oil leakage through two butterfly valves, it is advisable to install a drain and tundish arrangement near the outer valve, in a location where the drain valve can be conveniently observed. An arrangement for such a drain system is indicated in figure 5.24.2:
The drain should be left open at all times while discharging, Any leakage through the upper valve will be detected as a flow from the drain valve. The tundish and drain line will carry the drainage to the bilge. The tundish line may be fitted with an liquid or oil detector to provide remote indication of leakage. Any defects in the inner valve should be repaired at the earliest opportunity.

5.24.3 Logbook entries
The pumping performance of the ship should be entered in detail in the pumping log sheets, with main points entered in the deck logbook. Times of starting and finishing individual cargo tanks should be included. The time of pumproom inspections should be entered in each. If no problem are noted, the entry should indicate that the pumproom was found 'in apparent good order'. It is very important to log the times and reason for any delay or stoppage, including the party or equipment responsible for the stoppage and whether the stop was ordered by the ship or shore. Within the limits of safe operations, the discharge should proceed as requested by the receivers.
If any stoppage is caused by a failure of ship's equipment, full details of the efforts to make necessary repairs should be set down, including any obstructions or interferences to making repairs. It will be important for owners to be able to demonstrate due diligence in seeking a remedy to the delay and such demonstration cannot be made unless accurate records are maintained.

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