Saturday, June 8, 2013

OIL MEASURING STANDARD PROCEDURES AND TOOLS

OIL MEASURING STANDARD PROCEDURES AND TOOLS


* Oil measurement system
Measurements were made to obtain data that can be used to determine the quality and quantity of oil on each count movement

There are two systems of measurement of oil :
     1. Static measurement system
     2. Dynamic measurement system

Static measurement system
The measurement system is implemented when oil is at rest and require adequate settling time

Standard gauge
A standard measuring tool used to measure the physical properties of petroleum products, in the field or in the laboratory, according to standard methods that have been defined and used

Measuring tape (ASTM D.1085 or
 API 2545)
     a. A measuring tape that comes with scale spiki balls
     b. Use to measure the level of liquid oil and water contained in the tank hoard
     c. Measuring tape can be used to measure the free water if there is not water stick bar

Terms of measuring tape and the pendulum
a. Measurement methods innage or outage
    * Types of standard measuring tape ASTM D.1085 atau API 2545
    * Adjustable length of measuring tape with high tank
b. Standard pendulum
    * Spired
    * Scale
    * Fluid level more than 12 meter, weight 800 gram pendulum
    * Fluid level less than 12 meter, weight 600 gram pendulum

Water stick bar (ASTM D.1085)
Is the stick scale bar has a length of 1 meter. Use to measure the height of the free water in ground tank or tankers

Oil indicating paste
Seekers pasta oils that provide top level marking the measuring tape

Water indicating paste
Paste water search that provides top level marking BOB measuring tape or water stick bar

Hydrometer (ASTM D.1298 or API 2547)
Hydrometer cylinder of glass tube with inside diameter of the tube is not less of 25 mm which is to measure the density, specific gravity and API gravity of liquids

Range Hydrometer
   a. Pertamax, pertamax plus  0.700 s.d. 0.750
   b. Premium, avgas  0.700 s.d. 0.750
   c. Kerosene, avtur  0.750 s.d. 0.800
   d. Minyak solar  0.800 s.d. 0.850
   e. Minyak diesel  0.8500 s.d. 0.900
   f. Minyak bakar  0.900 s.d. 0.950
Accuracy rate readings 0.0001
Miniscus correction factor (Tabel 1 ASTM D.1298)

Cup/Flushing case assembly (ASTM D.1086 or API 2543)
An oil temperature gauge in the tank in the form of a thermometer scale oC or oF. At the bottom is equipped with a small 200 ml vessel, to accommodate the liquid to be measured temperatures

Weighted breaker/Bottle (ASTM D.270 or API 2545)
Tool used to take samples of oil contained in the tank

Centrifuge (ASTM D.96 or API 2542)
Tools to analyze water and sediment levels or centrifuge tube rotator (cone/pear) made of glass scale mm or %

Measuring cup
   a. See through
   b. Scale
   c. Size 1000 cc

Thermometer
   a. Standar IP 64 C
   b. Range -60 oC sampai dengan 102 oF - Range -60 oC to 102 oF

Automatic tank gauging (ATG)
Automatic measuring devices mounted on ground tank that can automatically measure level, temperature and density. Measurement results will be processed by computer

* Procedures for level measurement (ASTM D.1085 or API 2545)
Measurement methods
1. Innage method
This method measured the height of the liquid
2. Ullage atau outage method
This method measured the empty space in the tank or the distance from the surface fluid up to the point of measurement uncertainly in measuring the hole (reference point)
> Innage measurement method
> Measurement is carried out through a hole dip hatch or slot dipping device
> Basting oil paste tape measure around 10 cm above and below approximate height of the liquid
> During the measurement the measuring tape should always stick to the hole measuring point or reference point
> Decrease the measuring tape should be implemented gradually and on the surface liquid should not happen until the end of the pendulum feels ripples touched the table measuring or datum plate
> Inundation time measuring tape
   a. Minyak premium  antara 5 - 10 detik
   b. Minyak kerosene  antara 5 - 10 detik
   c. Minyak solar  antara 5 - 10 detik
   d. Minyak diesel  antara 10 - 30 detik
   e. Minyak bakar  antara 30 - 60 detik
> Slowly pull the tape and the tape should remain attached to the reference mark
> Repeat the measurement again and if the difference in outcomes is smaller than 3 mm then recorded as the measurement result
> If the result is equal to or greather than 3 mm should be measured re up to get 2 identical numbers

Example :
a. The first measurement 6831 mm
    The second measurement 6833 mm
    Size used 6831 mm
    Because 6833 mm less than 6831 mm
b. The first measurement 6831 mm
   The second measurement 6834 mm
    Repeat the measurement again due  6834 mm less than 3 mm dari 6831 mm
c. The first measurement 6831 mm
   The second measurement 6834 mm
   The third measurement 6836 mm
   Size used  6834 mm
   Because 6836 mm less than 6834 mm

* Procedures for temperature measurement (ASTM D.1085 
or API 2543)
a. Temperature measurements should be carried out as expeditiously as possible, appropriate and accurate because it is very directly influence the calculation results of oil
b. Thermometer used to have a level of accuracy +0.25 oC
c. Prior to used checked again kindness by comparing with standart thermometer
d. Thermometer used are ASTM thermometer scale oC or oF
e. Type is cup case or flushing case assembly

Conditions thermometer can not be used
1. Appointment on a scale of inaccurate readings
    a. Before use thermometer calibrated with a standart meter or master meter at room temperature
    b. Compare the reading on the scale of the appointment of each thermometer
    c. Thermometer can not used if there is a difference readings 1 oF or 0.5 oC
2. Column of mercury is lost
3. Mercury bulb is broken

The time required to dip the thermometer depends on the type of product
a. Oil having saybolt universal viscosity less than 100 seconds at 100 oF for 5 minutes
b. Oil having saybolt universal viscosity between 100 to 170 seconds at 210 oF for 15 minutes
c. Oil having saybolt universal viscosity above 170 seconds at 210 oF for 39 minuts

If the difference in air temperature and oil temperature measured over 20 oF or 11 oC, cup case flushing assembly should be rinsed several times with the oil temperature to be measured to accelerate the process of adaptation to temperature cup oil

Minimum number of measurements required temperature for different liquid depths the piled measurement.
High oil in the tank
The depth measurement
Temperature measurement
1. More than 5 m
    a. 1 m below the surface
    b. middle
    c. 1 m above the base
        a + b + c divide 3
2. Between 3 to 5 m
    a. 1 m dibawah permukaan
    b. 1 m diatas dasar
    a + b divide  2
3. Less than 3 m
   Middle (a) 
The procedure for the measurement of density
Density/SG/API measurement
Three kinds hydrometer
To measure
   1. Density (Metric system)
   2. Specific gravity (British system)
   3. API gravity (American system)

Density : Weight was a time of fluid in vacuum at a given volume in the temperature 15 oC (Kg/Ltr)

Specific gravity : Comparison between the weight of a term in a given volume at 60 oF with the weight of pure water at the same volume and the same volume as well (60 oF/60 oF)

API gravity : The function of specific gravity
API 60 oF/60 oF = {141.5 / SG 60 oF/60 oF} - 131.5

Measuring instrument
   1. Hydrometer (Density/SG/API gravity)
   2. Standard hydrometer
   3. Thermometer
   4. Hydrometer cylinder
Range hydrometer used depending on the type of oil being measured
Range density (Kg/Ltr)
   a. Minyak premium  0.700 s.d. 0.750
   b. Minyak kerosene  0.750 s.d. 0.800
   c. Minyak solar  0.800 s.d. 0.850
   d. Minyak diesel  0.850 s.d. 0.900
   e. Minyak bakar  0.900 s.d. 0.950

The procedures for the measurement
   1. Hydrometer in a clean and dry condition
   2. Hydrometer first tested with a standard hydrometer
   3. The difference in sample temperature with the temperature in the tank -/+ 3 oC
   4. Samples of oil poured into the hydrometer cylinder without creating froth and bubbles
   5. Insert the thermometer into the hydrometer cylinder
   6. Hydrometer should be perpendicular position and protected from the wind
   7. Dip hydrometer slowly and let it in a state of calm and press down approximately 2 scale
   8. If already in a state of calm, hydrometer scale reading then read the temperature of the samples as well
   9. How reading for invisibility oil in the surface of the flat line oil
   10. How readings for oil opaque in peak numbers miniscus that stick to the hydrometer and this figure is corrected with miniscus correction factor (Tabel 1 ASTM D.1298)

Way Hydrometer readings
Reading the scale on the viscous product, starting from the top and the concave surface of the liquid will be read from where the scale on the fluid rises. When this conditions occurs the miniscus scale reading can be corrected by the correction factor miniscus +/- 0.0001 > correction on the table miniscus

The sampling method
General definitions
Examination or test samples is an analysis of the oil sample using a certain amount of oil procedures or equipment or a specific time in order to obtain a picture or character or nature of the oils come from

Purpose :
   1. An early stage of the transaction
   2. To determine the conditions of properties
   3. As a guarantee or warranty
   4. Representatives of some or all of the oil
   5. Related to the economic value

The basic principle
Test the quality by sampling is either done manually or automatically. A representative sample of the results are considered representative of the population or the entire oil sampled. There are various methods of sampling and selection methods used adapted to the use of sampling itself

Sampling methods in the shore tank and vessel tank
Various methods of sampling for the purposes of knowing the quality of oil and counting oil quantity standard ASTM D.4057-95
   1. All level sample
   2. Running sample
   3. Spot sample
   4. Top sample
   5. Upper sample
   6. Middle sample
   7. Lower sample
   8. Clearance sample
   9. Bottom sample
   10. Drain sample
   11. Composite sample
   12. Single tank composite sample
   13. Multi tank composite sample
   14. Surface sample
   15. Outlet sample

All level sampel : 
1. SSample obtained by submerging the sealed sample bottle to a place as close as possible (draw off level outlet)
2. Then the sample bottle was uncorked by jerking the rope
3. Pull hard with speed such that fill the sample bottle as much as 3/4 parts (max 85%) as it appears on the surface of oil or liquids

Running sample :
1. Sample obtained by submerging the sample bottle from the surface exposed to the fluid same height as the bottom of the pit exit pipe or pipe hole swing
2. Then pull it back with a speed such that the sample bottle filled 3/4 parts, as it appears on the surface of the liquid

Spot sample :
Samples taken from some particular point in the tank by using a thief or sample bottle

Top sample :
Spot samples taken from 6 inchi (150 mm) below surface of the liquid

Upper sample :
Spot samples taken in the middle of the upper third of the oil content

Middle sample :
Spot samples taken from the middle of the oil content

Lower sample :
Spot sample taken at the same height with a hole in the pipe or pipe hole swing out from fixed roof tank

Clearance sample :
Samples taken 4 inches (100 mm) below the height of the pipe exit hole

Bottom sample :
Samples taken from the bottom of the tank, a storage area or at the lowest point of the pipeline

Drain sample :
Samples taken from the pipe exit (drain off) or shelfish (discharge valve). Sometimes drain sample same with bottom sample as the tank cars

Composite sample :
Samples obtained by mixing two or more spot samples are silent

Drain sample :
Samples taken from a tank in a proportional comparison. The term can also be used for a number of oil samples taken from the flow in the pipe

Single tank composite sample :
1. Samples obtained by mixing upper, middle or lower sample
2. For a tank like container equipped uniform vertical cylindrical tank, the mixture consisted of equal volumes of the three parts of the sample above
3. For horizontal cylindrical tank, the mixture consisting of 3 samples

Multiple tank composite sample :
Samples obtained by mixing of all samples from all levels compartments containing oil of the same type of oil in proportion to the contents of each compartments

Surface sample :
Spot samples taken from the surface of the liquid in the tank

Outlet sample :
Spot samples taken from the bottom of the tank at the tank outlet to the type of fixed or floating tank

Sample collection procedures :
1. Sample bottles down slowly until it touches the bottom of the tank, the height of the sample bottle hole 33 cm from the bottom of the tank
2. Gently pull and place it at the height of the tank outlet hole (bottom/lower)
3. Snapped the rope so that the sample bottle lid open and let the moment (1 to 2 minutes) until the bottle is filled
4. Drag it to the surface and pour the sample into a place (sample can) that has been provided
5. Other samples were taken completely clean and slowly lower into the tank until mid-height (middle)
6. Do as point 3 and 4
7. Other samples were taken completely clean and slowly lower the tank up to the desired position in
8. Do as point 3 and 4

Sampling in tanks ashore
Tools to be used :
   1. Weighted breaker/bottle
   2. Sample container

Spot sample collection procedures (ASTM D.4057)
High oil in the tank
   1. More than > 4.5 m
   2. Between 3-4.5 m
   3. Less than 3 m
The depth measurement
1. A. Upper sample
    B. Middle sample
    C. Lower sample
2. A. Upper sample
    B. Lower sample
3. A. Middle sample
Samples examined
1. A+B+C
2. A+B
3. A

Procedures for measuring the liquid in the ship tank (ASTM D.1085 
or API 2545)
1. Ordinance basically tank level measurements in the same boat with the procedure of measurement in tanks ashore
2. Measurement method outage
3. Some of which need to be considered
    a. The ship's position
    * Even keel (sama rata) - Equally
    * Trim or different fore draft and after draft
    * The list of the ship (angle of the heel ), left (port) or right (starboard)
    b. Trim correction factors and calibration tables heel on the ship

Tankers Gauge
On a big tanker compartment is equipped with an automatic means of measuring devices installed permanently ( Master level). Data measurement results are automatically processed by a computer.
In the small tanker which was not equipped with a master level, level measurement using a UTI ( Ullage Temperature and oil/water Interface) measurement devices for closed and restricted applications.

Ships tank sampling
Tools used :
a. Weighted breaker/bottle
b. Sample container
There are two ways of sampling on board :
1. Sampling was conducted on the entire compartment even in the same compartement type oil
2. When a tanker load of oil equivalent, sampling done in the compartment as in the following data

Number of compartments
a. 1 s.d. 2
b. 3 s.d. 6
c. 7 s.d. 12
d. Lebih dari 12 - More than 12

Samples taken
a. In each compartment
b. 3 compartments similar to oil
c. 5 compartments similar to oil
d. 7 compartments similar to oil
Weakness of the latter
Can impact the lact of accurate in calculating the volume of oil in tankers

Measurement methods crossing density and temperature measured only in the compartment 1P, 2S, 3P dan 4S. For the density and temperature 1S=1P 2P=2S 3S=3P dan 4P=4S. Sampling of cross impact on the calculation of the volume is not accurate because of the temperature and density the compartment that is not measured is not necessarily the same as the measured compartment. Oil temperature in the compartment is affected by ambient temperature

Determination of sampling methods
1. Decision making method of sampling is strongly influenced by the condition of the oil to be in the sampling
2. Recommended oils made specifically for mutual agreement between sender and receiver
3. Sampling locations
4. Methods (automatic and manual)

Sampling on the tank
System manually following the oil height top/middle/bottom (static/transfer)

Sampling on tankers and barges
1. Multiple tank composite sample
2. Take a sample from each individual compartment subsequent blending

Sampling in the distribution system through a pipe
1. Automatic sampler (recommended)
2. Continuous sample

Dynamic measurement system
The measurement system is implemented in a state at the time of the oil flow and thus does not require settling time

Metering system
Metering system is one type of measure that can be used as a transfer point determination in carrying out the handover of a product (transfer of rights).
Magnitude numbers shown in metering system is used as a guide indetermining the amount or volume of products handed.
In order for the appointment of metering system is accurate or not a large deviation occurs before the first operation should be tested by a master meter or meter prover.

Flowmeter
1. Positive displacement flowmeter
2. Turbine flowmeter
3. Cariolis
4. Ultrasonic

Meter prover : Function to calibrate the flowmeter in order to yield more accurate measurements so that deviations that occur in the process of measurement become smaller

Flowmeter
Migas Approval             Oil   Gas
PD Meter                      Yes  No
Turbine meter                Yes  Yes
Orifice (Dual chamber)   No  Yes
Ultrasonic meter             No   Yes

Difference metering system with Manual tank gauging
Metering system no influence accuracy of human resources, tanks, pipes and gauges.
Manual tank gauging very influential.

Metering system have accuracy up 99.975 %
Manual tank gauging must be in tolerance for 0.5 %

Metering system truth can be proved by proving system
Manual tank gauging difficult to be proved

Metering system if the question can be proven
Manual tank gauging difficult to be proven

Metering system do quality insurance THP prover and instrument accessories
Manual tank gauging difficult to find a fit

Metering system repeatability value < 0.05 %
Manual tank gauging repeatability value until 0.5 %

Metering system repeatability < 0.02 %  inearity operation 0.15 %
Manual tank gauging no calculations

Operation metering system
Operation of the metering system basically is running a command or provisions contained in the SOP metering system itself.
Level of success in operating the metering system is influenced.
SOP are clear and correct.
Skilled human resources.

Procedures for calculation with ASTM table

Oil quantity calculation policies
1. Using ground tank calibration table or tank tanker
2. Using ASTM-IP table

Legal basis
By ordonance tera 1949 and Republic of Indonesia law No. 2 Tahun 1981
concerning legal metrology.
In the calculation of the quantity of oil using ASTM-IP table metric system

In indonesia to calculate the volume of oil to use Tabel ASTM-IP 1953


Modul : Loading Master Training

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