5 Years Docking Service
General Information
Every 5 years, when the vessel’s dry dock service is planned, we recommend including the boiler system in the plans. Even though the expected service life of the gaskets in oil/steam ball valves is relatively long, we have experienced that they typically start to leak after some years. Since the leaks start as minor leaks and take a relatively long time to repair, it is quite common that no action is taken, meaning that the leaks will get bigger over time. So, the 5-year docking is the perfect opportunity to overhaul the system.
We are specialised in completing these major docking overhauls of Aalborg KBSD boiler systems and have extensive experience with them. We can tailor these services to each client’s wishes and add or subtract extra parts/services to our general package.
We generally recommend a complete overhaul of any Aalborg KBSD boiler system, and our general package includes what is shown in the headlines in the below table. Overhaul and installation usually take approximately two working days per boiler, and commissioning and testing typically take about a day.
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What is done in the service?
The 5 years docking service of Aalborg KBDS burners, is a major service where all the mechanical and electrical components are overhauled and/or checked, and in this section, the overhaul procedure is described in details.
Although the main objective of the docking service is to overhaul the fuel oil line and its components, we also focus on the control system, feed water valve, pilot burner and FD fan. If the boiler system uses Mission Control as control system, we visually check the Unisab controllers and replace the back-up batteries in them. In cases where we have reason to believe the condition of a Unisab controller is not good, we recommend to replace Unisab in question. Besides that we replace the 24v power supplies, timer relays and the sockets for the PR modules. Overhauling steam/water globe valves is normally shipyard scope, but we check the feed water regulating valve, where we normally recommend to replace the diaphragm in the actuator, the filter regulator and positioner. If the FD fan is using a pneumatic actuator, we replace the O-rings in the air cylinder and replace the filter regulator and we recommend to replace the positioner. The O-rings are also replaced in the pilot burner air cylinder.
The below drawing and table show the work on the fuel oil line and its components. Please note that positions P, Q, R and S on the drawing are only present in boiler systems installed with two separate fuel oil lines for HFO/DO and MGO – a so-called double string system. Kindly note that overhauling these valves and actuators and replacing the solenoid valves is not a part of the general package and one extra days work per boiler should be expected, in services where these items requires overhaul. For boiler systems which includes these items, we do however recommend that these items are included in the overhauled.
Position | Component | Overhaul action |
A | Manual 3-way oil ball valve | Replace gaskets inside valve |
B | Manual 3-way oil ball valve | Replace gaskets inside valve |
C1 | Flow meter – mechanical or Coriolis flow meter is installed. | Mechanical flow meter overhaul – replace ball bearings and O-rings |
C2 | Flow meter – mechanical or Coriolis flow meter is installed. | Coriolis flow meter cannot be overhauled |
D1 | Fuel oil regulating valve – electric or pneumatic reg. valve is installed | Pneumatic valve – overhaul valve and replace IP converter |
D2 | Fuel oil regulating valve – electric or pneumatic reg. valve is installed | Electric reg. valve with ES11 box – recommend to replace ES11 box |
D3 | Fuel oil regulating valve – electric or pneumatic reg. valve is installed | Electric reg valve without ES11 box – no overhaul |
E | Automatic 3-way oil ball valve with pneumatic actuator | Replace gaskets in valve and actuator, replace solenoid valve and quick release valve |
F | Automatic 2-way oil ball valve with pneumatic actuator | Replace gaskets in valve and actuator, replace solenoid valve and quick release valve |
G | Automatic 2-way steam purge ball valve with pneumatic actuator | Replace gaskets in valve and actuator, replace solenoid valve and quick release valve |
H | None-return valve | No overhaul – replace gaskets before and after the valve |
I | Manual 2-way oil ball valve | Replace gaskets in valve |
J | Manual 2-way steam ball valve | Replace gaskets in valve |
K | Automatic 2-way atomizing steam ball valve with pneumatic actuator | Replace gaskets in valve and actuator, replace solenoid valve and quick release valve |
L | Regulating globe valve for atomizing steam pressure | No overhaul |
M | Manual 2-way ball valve for atomizing air | Replace gaskets inside valve |
N | Manual globe valve for atomizing steam | No overhaul |
O | None-return valve | No overhaul – replace gaskets before and after the valve |
P | Automatic 3-way ball oil valve with pneumatic actuator | Replace gaskets in valve and actuator and replace solenoid valve |
Q | Automatic 2-way oil valve with pneumatic actuator | Replace gaskets in valve and actuator and replace solenoid valve |
R | Manual globe valve for HFO bypass | No overhaul |
S | Automatic 3-way ball oil valve with pneumatic actuator | Replace gaskets in valve and actuator and replace solenoid valve |
If you have any questions about what we can offer for your specific boiler system, please don’t hesitate to do contacts us. As mentioned above, we have extensive experience with docking services, and we have successfully completed more than 20 of them in the company’s first two years. So, we can give you immediate info, suggestions and ideas and offer a cost estimate within hours.
We usually have all the required parts in stock, and in exceptional cases, we can complete the overhaul in port or at anchorage with the correct assistance.
Pre-dock inspection
Free of charge
The pre-dock inspection is an inspection which should be completed approximately two to four weeks before the docking. Here the boiler system is evaluated to check if any special work/parts are required.
If the inspection is completed in one day, and if WWMA is booked to complete the docking service, the inspection is free of charge, and only the expenses will be invoiced. In cases where one additional day is needed for travel, EUR 400 will be invoiced for that day. The standard service rate will be invoiced for additional hours on top of the first additional day. If WWMA does not complete the docking service, the pre-dock inspection will be invoiced according to WWMA’s standard service rate. Furthermore, the free-of-charge inspection is based only on the inspection and minor tool-less adjustments. In cases where service work is needed during the pre-dock inspection, the work will be invoiced according to our standard service rate.
