Ullage Survey :
Ship Cargo tanks full capacity has charged due to a modification or is not accurately calculated. In this case, the internal Electro-Optical Distance Ranging Method (EODM) by 3D laser scanning supported by our advanced software is required. This method is ideal for every ship but especially for floating storage Vessels, delivery barges, chemical tankers, bunker tanks etc.., where accuracy is very important. Dip stick or ullage bar are engraved with large legible markings for ease of readings. After Barge/Vessel tank calibrations, deliverables are ullage tables which is the load calculation method of determining ship carrying liquid cargo.
The volume of liquid cargo, such as crude oil, petroleum products, chemicals, and similar products loading or discharging on tanker ships, is determined by using ullage survey method. It is, in short, a weight calculation method. Based on measuring the empty space above the cargo in the tanks and performing basic static calculations, this method is used. By using the ullage survey , ship’s cargo weight easily determined by advanced 3D Scanning technology.
The ullage method refers to the measurement of the distance (i.e., the space) between the liquid’s surface and the top of the inner surface of a tank. Ullage tables are located on the ships. These tables are produced in relation to a tank’s interior volume as measured from a reference point. The sounding method is the opposite of Ullage method. This approach involves measuring the distance between various reference points at the tank’s bottom and the liquid’s surface to determine the depth of a tank of liquid.
Frequency of Sounding Survey and Ullage Survey:
Frequency of sounding and ullage may depends upon the ship owners requirements.
1.All the fuel storage tank,lube oil tank and diesel oil tank may sounded twice in a day to ensure any leak or any other related to oil loss.
2.All the waste water tank and bilge tank sounded twice in a day.
3.Frequency of sounding in a Ballast water tank and fresh water tank is once in a day.
5.During ballasting or deballasting of the tanks are going on, it is taken in every hour.
6.During waste water transferring or discharging overboard through 15ppm equipment in a of ship ,it is doing 2 or 3 times in every one hour.