Ballast Water Management System

Ships need ballast water for many reasons: To achieve the sufficient draft and stability To reduce stress on structure integrity To correct the list or trim Ships carry ballast water to maintain stability in rough seas and when sailing without cargo. After a vessel has been unloaded the water is typically pumped into purpose-built tanks onboard. It is then drained during loading at the destination port, bringing ashore organisms which pose environmental and even health risks. This is suspected to have contributed toward a cholera outbreak in Peru – bệnh dịch tả hoành hành tại Peru that affected over 10,000 people. The International … Continue reading Ballast Water Management System

ODME – Oil discharge monitoring equipment

Oil tankers carry different types of oil cargo in their cargo tanks and it often happens that after discharging the oil cargo in some port, the ship sails without any cargo to some other destination. In order to do so, it has to take ballast from the sea to get better draught and stability. For this reason, ballast water is taken into cargo tanks wherein generally oil cargo would have been carried. It is to note that the ballast water carried in cargo tank has to be discharged out at sea before the next cargo loading. Therefore, Oil Discharge monitoring … Continue reading ODME – Oil discharge monitoring equipment

Pitfalls of Pump Piping design

Rule No. 1 Position the pump in an accessible location. When laying out the system, give some consideration to the people who eventually will have to look after the pump that easy access and working room for routine maintenance. Also, make sure overhead space is adequate for lifting devices and working clearance. Rule No. 2 Make the pipe diameter on both the inlet and the outlet sides of the pump at least one size larger than the nozzle itself. On the horizontal inlet side, an eccentric reducer is required to decrease the size of the pipe from the suction line … Continue reading Pitfalls of Pump Piping design

MGPS – Marine gross protection system

Marine growth in sea chests, box coolers and seawater piping systems is a potential threat for the performance and condition of your ship or installation. Blockages caused by barnacles (hầu)  and mussels (trai) are expensive and time consuming to remove and can have serious consequences. Engines will run at abnormally high temperatures, resulting in unnecessary increased fuel consumption and lower performance. To combat this risk the Marine Growth Prevention System (MGPS) was developed. Once installed it provides low maintenance and continuous protection against most hard and soft foulings as well as corrosion. The Marine Growth Prevention System utilizes an impressed … Continue reading MGPS – Marine gross protection system

MARINE COROSSION AND PROTECTION (Part 2)

Continuing on MARINE COROSSION AND PROTECTION (Part 1) that we discussed about the Electro-chemical corrosion protection methods and the last remained one is called ICCP system. Reversing the current by creating an opposite potential ( ICCP : Impressed current corrosion protection ) The ICCP system, a large positive current is applied to hull and pass through the adjacent water. As a result, current flow into ship’s steel whereas it has a direct unprotected contact with seawater and inducing a Cathodic reaction that protect the steel against the corrosion. To achieve this, the Rectifier (convert AC–>DC) is connected to ship’s steel with … Continue reading MARINE COROSSION AND PROTECTION (Part 2)

PUMP PRIMING (Notes)

When the centrifugal pump is not primed ( filled with liquid ) before starting, the air pocket inside the pump case may give rise to formation of vortex and discontinuity of flow  those lead to make noise, vibration and damages to the impeller. Priming is done by pouring liquid in to pump casing ( when pump is not running ) through a funnel and air will be displaced through an air vent provided on pump case. The formation of air pocket inside casing can be avoided by following methods: 1 – Installation of pump below the suction level 2 – … Continue reading PUMP PRIMING (Notes)

CENTRIFUGAL PUMP (Advanced)

There’re some confusing fluid mechanic principles, you may understand it during learning individually. Meanwhile, it’s real difficult and daunting  to gather and compile all the theories to design a reasonable pump configuration as the demand. In this post, we’ll break down the anatomy of all concept through the centrifugal pump curve (Characteristic curves). The pump characteristic curve shows the performance of a pump. It usually shows TDH-Total dynamic Head, Power, Efficiency and NPSHr plotted over Flow rate at a given RPM. In these diagrams you can estimate pump behavior at constant speeds and a range of impeller diameters. Constant horsepower, … Continue reading CENTRIFUGAL PUMP (Advanced)

CENTRIFUGAL PUMP (Introduction)

Well for the inspectors, trainees, and freshers who just move into the piping systems will have their introduction, with fluid transporting devices which are mainly “PUMPS“. Almost piping system have the basic and the mostly optimized device know as centrifugal pump those are  handled easily and  it is cheaper when compared to other pumping devices, even maintenance cost is much lesser than the others. But the LIMITATION ( •cannot handle entrained air – 3%max •cannot handle viscous liquids) THERE’RE 5 MAIN PUMP STYLES: 1-Horizontal Split Case good wear resistance (Mean of higher price ) suction and inlet are opposite high head pressure ( Cooling … Continue reading CENTRIFUGAL PUMP (Introduction)

EDUCTOR AND EJECTOR – in shipbuilding, industrial (How to distinguish, calculation, selection, and purchasing)

  At the beginning, there’s no need to fret over the differences that the different is in the motive fluid: An ejector uses a gas phase motive, usually steam or air.  An eductor uses a liquid phase motive, usually water.  Eductors/Ejectors … Continue reading EDUCTOR AND EJECTOR – in shipbuilding, industrial (How to distinguish, calculation, selection, and purchasing)