OilcalcsPro for desktop 101 – Part 4

In our last post concerning OilcalcsPro for desktop 101 we discussed some more calculations using the main calculator.

We also talked about the two simple fuel blenders, the problems encountered when loading two components of different temperature and density and the shrinkage caused by mixing two components with different densities. And finally we discussed how the viscosity blender works.

In today’s tutorial we are going to talk about the following topics:

  • The visco – temp converter

  • LPG/NGL calculations – liquid

  • LPG/NGL calculations – vapor

If you are interested in following the examples on your own machine, the latest version of OilcalcsPro For Desktop can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

So let’s get started with the visco – temp converter: to get to it click ‘Tools’ in the main screen, then click ‘Viscosity/temp conversion’ in the tools screen.

This utitility does the following things:

  • For a given temperature / viscosity combination it calculates and displays the viscosity/temperature graph using the ‘V50’ formula.

  • For two pairs of temperature and viscosity it calculates and displays the viscosity/temperature graph using the ‘Walthers equation.

  • For a given viscosity it will calculate the corresponding temperature, either using the V50 formula or the Walthers equation.

  • For a given temperature it will calculate the corresponding viscosity, either using the V50 formula or the Walthers equation.

The viscosity is in cSt, the temperature can be either in degrees Celsius or Fahrenheit.

Looking at the below screenshot, let’s have a look at the various controls:

V50 graph

V50 graph

In the top left corner you can see the V50 calculator: only one viscosity and one temperature are entered to enable displaying the graph. In the V50 calculator is a button that shows ‘°C’. If you press it, the temperature values will automatically be converted to degrees Fahrenheit, and you can then also enter your temperature values in degrees Fahrenheit. After converting to degrees Celsius, the temperature button now shows the text ‘°F’, and if you click it again, temperatures will be converted from degrees Fahrenheit back to Celsius.

The viscosity and the temperature field in the top are the ones used to calculate the V50 graph. Below that are two more fields for viscosity and temperature; if you enter an alternative viscosity, the corresponding temperature is calculated and displayed in the second temperature field. Likewise if you enter an alternative temperature, the corresponding viscosity is calculated and displayed in the second viscosity field.

For a practical example, enter a value of 380 cSt and 50°C in the two fields in the top. As soon as you enter the values, the graph is automatically drawn. Above the graph there is a drop-down field where you can choose the maximum viscosity value to be plotted in the graph, and there is a button that presently says ‘Graph – single reference’. Clicking this button lets you switch between showing the V50 and the Walther graph.

Below the graph there is a check-box  that says ‘switch graph automatically when switching between Walther and V50; by default the check-box is ticked, so that when you enter a new value in the V50 calculator, automatically the V50 graph is drawn, and if you enter a new value in the Walther calculator, automatically the Walther graph is drawn and displayed.

Now if you enter a value of 500 in the alternative viscosity field, the temperature field will show 45.8°C. Conversely, if you enter a value of 49 in the alternative temperature field, the viscosity field will show 405 cSt. By default the viscosity range drop down is set at 500 cSt. If you change it to for example 1000 cSt, the graph is redrawn and the viscosity and temperature axis are both automatically adjusted.

Now lets make an example using the Walther equation: the Walther formula is usually written as: log10*log10*cS+a) = log10(log10*b+1/Tc). Using two sets of viscosity and temperature values, a and b can be solved and hence the graph can be calculated and plotted. Let’s enter the following values in the Walther calculator:

  • 950 cSt at 18°C

  • 120 cSt at 100°C

In below screenshot the graph is plotted for these values; if you now enter an alternative temperature of 50°C, you will see a calculated viscosity of 364.1 cSt for the corresponding viscosity:

Walther graph

Walther graph

By changing the viscosity range value in the drop down field, you can force the y-axis to a different viscosity maxima, with a maximum of 4,000 cSt.

Please note that while the V50 formula is good enough for a quick and easy approximation, it is not quite as accurate as the Walther formula. The V50 formula provides a reasonable estimate for viscosity / temperature conversions in the temperature range between approximately 30 °C and 120 °C for well known bunker fuels such as RMG 380.

If you need an accurate estimate for any fuel, definitely the Walther formula is the recommended one to use.

Next up is the LPG/NGL liquid calculation: this calculator can be used to calculate weights and volumes of a known quantity of LPG or NGL in a shore tank or ship tank.

To get there, click ‘Return’ on the visco/temp converter, and then in the tools screen, click the ‘LPG/NGL Calculation – Liquid.

To calculate the quantity of LPG or NGL, the following parameters are required:

  • Relative density at 60°F or density at 15°C

  • Liquid temperature

  • Shrink factor of the tank

  • Observed liquid volume

If you enter the relative density, this will automatically be converted to density at 15°C. This density will be used to calculate the CTL, using the calculations as described in API MPMS 11.2.4 (ASTM Technical Publication TP27).

The shrink factor is assumed to be 1 if no entry is made. Normally, the tank tables for the tank in question will provide the shrink factor, based on the liquid observed temperature.

Table 56 for conversion of weight in vacuo to air is calculated using:

T56 = (1 – (1.2 / dens15)) / (1 – (1.2 / 8100)).

After entering also the observed volume in M³, weight in vacuo and air are calculated using T56.

Now let us carry out an example: enter a relative density of 485, a liquid temperature of -15°C, a shrink factor of 0.99858 and an observed volume of 500 M³. You will see the density at 15°C is 485.4, the CTL is calculated at 1.08970 and T56 is calculated at 0.99768.

The resulting weight in vacuo is 264.095 MT, and the resulting weight in air is  263.481 MT.

The LPG/NGL calculator – vapor works a bit differently: in order to calculate the density of the vapor, the following formula is used:

d15= (288.15 * absPx * MolWeight) / (liqTemp * atmPx * 23.6382)

Where:

  • d15 is vapor density at 15°C

  • absPx is the absolute tank pressure in kPa

  • MolWeight is the molecular weight of the vapor, approximately 44 for LPG and depending on the specific composition. For LNG (or NGL as it is also referred to), the molweight is approximately 18, again depending on the actual composition.

  • liqTemp is the observed liquid temperature in °C

  • AtmPx is the atmospheric pressure in kPa

Both the molecular weight and density at 15°C are normally provided with the quality certificate, but the density can also be calculated using for example the revised Klosek-McKinley method. That is however a topic worthy of an entire blog post in itself.

Let us now do an example: head over to the LPG/NGL vapor calculator by first clicking ‘Return’ inside the LPG/NGL liquid calculator, then click the ‘LPG/NGL calculator – vapor’ in the tools screen.

Assume the following values:

  • Vapor temperature: -135°C

  • Tank vapor pressure: 5.6 kPa

  • Atmospheric pressure: 101.3 kPa

  • Molecular weight: 16.5

  • Vapor observed volume: 200 M³

  • Shrink factor: 0.99954

The vapor density is calculated as 1.433 and the resulting weight in vacuo is 286.468 Kg (not MT!).

Well, we have come to the end of this tutorial! In the next tutorial we will talk about the following topics:

  • LPG density calculation

  • LPG/NGL conversions

  • Oil conversions

If you are interested in following the examples on your own machine, the latest version of OilcalcsPro For Desktop can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal.

 

 

OilcalcsPro for desktop 101 – Part 3

In our last post concerning OilcalcsPro for desktop 101 we discussed:

  • Using pressure and thermal expansion coefficient inputs

  • The different oil types

  • Converting between different density units

  • Some real life calculation examples

In today’s tutorial we will look at the following items:

  • More calculations using the main calculator

  • Fuel Blending – two components

  • Fuel density after blending

  • The visco blender

If you are interested in following the examples on your own machine, the latest version of OilcalcsPro For Desktop can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

In the previous tutorial we saw two examples using the main calculator; one example using table 6B and one example using table 54A. We will now show you a few more examples for lubricating oils, special applications and LPG/NGL:

To start with a lub oil example: Say we have 500 liters of a certain lubricating oil, at an observed temperature of  28.6°C and a density at 15°C in vacuo of 881.3. What are the weights and standard volumes for this quantity of oil, using SI Metric standards?

Before we start calculating, lets head to the settings page and ensure the following settings:

  • SI Metric

  • Use table 56

  • Use 2004 tables

Back in the main calculator screen, select ‘Luboils’ in the oil type drop down box, and enter the density of 881.3 in the density field, enter the temperature of 28.6 in the temperature field, and enter the volume of 500 in the volume field.

The display now shows the following results:

  • VCF: 0.99028

  • GSV: 495.140

  • MT(Vac): 436.367

  • MT(Air): 435.839

  • LTons: 428.96

  • Bbls: 3,116

  • US Gallons: 130,872

Since we are using the metric standard, and have chosen luboil as the oil type, the VCF has been calculated using table 54D.

Special applications example:

A shore tank contains 5,000 Barrels of  99% + denatured fuel ethanol, with an API gravity of 53.89 at 60°F and a temperature of 62.5°F. The alpha coefficient is 0.000599 /°F or 0.001078 /°C. What are the weights and standard volumes using Imperial Standards?

First, in the settings page, change from SI Metric to Imperial, other settings can remain the same.

Then back in the main calculator page, select  ‘Special Applications’ in the oil type drop down box. Select ‘GOV Bbls’ in the volume drop down box, select ‘API60’ in the density drop down box, and select ‘/deg F’ in the thermal expansion coefficient drop down box. And select ‘deg F’ in the temperature drop down box.

Now enter the API of 53.89 in the density field, enter 5000 in the volume field, enter 62.5 in the temperature field, and enter the alpha of 0.000599 in the thermal expansion coefficient field.

The results display will show the following values:

  • VCF: 0.99850

  • GOV: 5,000

  • GSV: 793.744 (in M³ at 60°F)

  • MT(Vac): 605.234

  • MT(Air): 604.372

  • LTons: 594.83

  • Bbls: 4,993

  • US Gallons: 209,706

The following screen shot shows the above calculation, please note the settings of the various drop down boxes:

Example calculation

Example calculation

LPG/NGL example:

The temperature corrections for LPG and NGL are all calculated in accordance with GPA Technical Publication TP-27, edition 2007 and the setting 2004 tables / 1980 tables has no effect when calculating for LPG/NGL. Also the setting SI Metric or Imperial has no effect on the calculation of the temperature correction factor. This setting does however effect how volumes and weights are calculated.

Right, lets start off with an example using the SI Metric standard:

A tank contains 5,000 M³ of LPG at a temperature of 12°C, and a density at 20°C in vacuo of 518.7 kg/M³. What are the weights and volumes using SI Metric Standards?

Like in the other examples, check in the settings page that SI Metric standards is checked. Then in the density drop down box select ‘dens20’, in the volume drop down box select ‘GOV M³’, and in the temperature drop down box select ‘deg C’. Enter 518.7 in the density field, 5000 in the volume field and 12 in the temperature field.

The results display will show the following:

  • VCF: 1.02114

  • GSV (M³-20°C): 5,105.700

  • MT(Vac): 2,648.327

  • MT(Air): 2,642.600

  • LTons: 2,600.86

  • Bbls: 32,162

  • US Gallons: 1,350,804

Please note that the GSV is at 20°C because the density is at 20°C. If you would like to know the GSV at 15°C instead, then after entering the various values in the designated fields, select ‘dens15’ in the density drop down box. The density field will be updated and will now show a value of 525.6, and the GSV shows now at 15°C. Please note that the weights have not really changed, any change is due to rounding differences.

Right, lets move on to our next topic, Fuel Blending – two components:

When you click ‘Tools’ in the main calculator screen, you are presented with the Tools screen, and the first utility there is the ‘Fuel Blend – two components’ utility. The idea here is to enter two quantities of fuel of known density and temperature.

The application will calculate the blended density, the average temperature, the shrinkage caused by the blending, and last but not least it will indicate which component should be loaded first, based on the calculated weight correction factor for each component.

Especially when densities are far apart and there is a significant difference in temperature of the two, it is not always obvious which component should be loaded first in order to obtain a good blend. If the heavier component has been heated up to a considerably higher temperature than the lighter component, it may well be that the component with the lower density should be loaded first due to the fact that its weight correction factor is higher than that of the component with the higher density.

Let us first look at an example of blending two fuel oils on board: we have two parcels, with the following details:

parcel 1:

  • volume = 10000 M³

  • temperature = 35°C

  • density = 954

and parcel 2:

  • volume = 10000 M³

  • temperature = 50°C

  • density = 962

Lets make sure that in the settings screen we have selected SI Metric and 2004 tables. Heading to the blend tool screen, enter the data as listed above and note that the button in the lower right corner of the screen shows ‘Product’. You can do these calculations for either crude, products or luboils. When mixing crude and product, choose the oil type which is represented by the larger quantity.

After entering the data, the results display will show:

  • GOV(M³): 20,000.000

  • Shrinkage: 0.02 M³

  • Nett Volume: 19,999.981

  • Avg temp: 42.5

  • density: 958

  • M³ 15°C: 19,606.581

  • MT Vac: 18,783.105

  • MT Air: 18,762.322

  • Bbls 60F: 123,371

  • First to load: 1

As you can see in this example, even though the density of component 1 is lighter than the density of the 2nd component, component 1 must be loaded first due to the considerably higher temperature of component 2.

Shrinkage comes into play mostly when there is a big difference in density, for example when discharging fuel oil into a shore tank that already contains a significant amount of crude oil with a density of say 100 points less than the density of the fuel oil being discharged.

Lets make another example, this time with two components with a big difference in density:

parcel 1:

  • volume = 50,000 M³

  • temperature = 35°C

  • density = 990

and parcel 2:

  • volume = 50,000 M³

  • temperature = 32°C

  • density = 862

After entering the data, the results display will show:

  • GOV(M³): 100,000.000

  • Shrinkage: 63.33 M³ / 0.063%

  • Nett Volume: 99,936.670

  • Avg temp: 33.5

  • density: 926.6

  • M³ 15°C: 98,558.543

  • MT Vac: 91,324.346

  • MT Air: 91,219.874

  • Bbls 60F: 620,169

  • First to load: 1

As you can see from this example, the shrinkage is 63 M³! If we are discharging component 1 from our vessel into a shore tank which already contains component 2, it actually means that our outturn has been reduced by 63 M³ / 0.126% as a result of mixing with this lower density shore tank.

Next up is the ‘Fuel density after blend’ module: the concept is slightly different in that we have a tank with a known volume, density and temperature, and load into that tank a second component with known density. After loading we observe the total volume and the new observed temperature, and based on that data we calculate the new density.

For an example, consider the following scenario: the tank contains 10000 M³ of fuel oil with a density of 990, and a temperature of 36.2°C. We load a second component into the tank, with a density of 945. The final volume is 20,000 M³ and the final temperature is 38.5°C. What is the resulting density?

First enter volume, density and temperature in the ‘tank before blending’ frame. Then enter final volume, density of 2nd component and final temperature. The final density is displayed as 967.5.

This utility also calculates for crude, products and lubrication oils.

Next up is the visco blender:

The visco blender contains two functions:

1. It allows you to blend a maximum of 10 components and calculate the resulting density, viscosity, pour point and flash point. The ten components are stored in a database for easy retrieval / editing.

2. It can calculate the fractions of two components with a known viscosity in order to reach a target viscosity.

To start of with item 2) here is an example: lets say we need a quantity of 5,000 Mtons of fuel with a viscosity of 380 cSt, and we have two components available: one with a viscosity of 500 cSt and one with a viscosity of 220 cSt. How much quantity of each do we need to get the target viscosity of 380? As you can see in the below screenshot, the distribution calculator is very simple: you just key in your target quantity (whether M³ or Mtons), enter the viscosity for each component, and enter the target viscosity:

Fractions calculator

Fractions calculator

 As you can see in the screenshot above, the calculator has come up with a quantity of 3,404.9 for the 500 cSt component and 1,595.1 for the 220 cSt component. For those of you curious to know what happens behind the scenes:

The calculator uses the viscosity blend number to calculate mix viscosity: first the blend number VBN is calculated for each participating viscosity using the following formula (often referred to as the Refutas method):

VBN1 = 14.534 * Math.log(Math.log(V1+0.8)) + 10.975;
VBN2 = 14.534 * Math.log(Math.log(V2+0.8)) + 10.975;

Then, the VBN is calculated for the target viscosity:

VBN = 14.534 * Math.log(Math.log(VTarget+0.8)) + 10.975;

And finally, the quantity of each component is calculated using the difference between target viscosity blend number and individual visco blend number divided by the difference between the two participating visco blend numbers:

X1 = (VBN – VBN2) / (VBN1 – VBN2);
X2 = 1 – X1;

Now to move on to the actual visco blender: as I mentioned above, the visco blender can accommodate a maximum of 10 (ten) components; for each component you enter the density at 15°C in vacuo (or the API at 60°F if you are using Imperial standards, in accordance with your settings), the volume or weight (if you enter volume, weight is calculated and vice versa), the viscosity in cSt, the flash point and pour point.

Please note that for the temperature values too, if you are using Imperial standards, temperature values are shown in deg Fahrenheit and if you are using SI Metric standards the temperatures are shown in deg Celsius.

Internally, all values are converted to SI Metric standards, how they are displayed depends on whether you have chosen Imperial or Metric standards in settings.

Above the various fields for volume, density etc there is a drop down list on the left side, where you select the number of the component you wish to change or enter data for. To the right of this drop down is a button called ‘Clear All’. Using this button you can either clear the presently selected component, or you can clear the entire database. When you click the button, a message box comes up asking if you want to clear all entries or only the current one. If you press ‘Cancel’ only the current entry will be deleted, if you press ‘OK’ all entries will be cleared.

Let us make an example now, using two components with the following data:

component 1:

  • Volume = 1,000 M³
  • density = 990
  • Viscosity = 500 cSt
  • Flash point = 62 °C
  • Pour point = 12 °C

component 2:

  • Volume = 1,000 M³
  • density = 945
  • Viscosity = 380 cSt
  • Flash point = 60 °C
  • Pour point = 5 °C

After entering both components, the results are:

  • Viscosity = 436.6 cSt
  • Density = 967.5
  • Flash point = 61 °C
  • Pour point = 8.8 °C

In this calculator too, the Refutas method is used for calculating the resulting viscosity. For calculating pour point and flash point also empirical formulas using blending index numbers are used to establish the mix pour point and flash point.

Below two screenshots of the results: one using SI Metric standards and the next one using Imperial standards. Volume, density and temperatures are automatically converted from Metric to Imperial when viewing the data and the results:

Visco blender Metric

Visco blender Metric

Visco blender Imperial

Visco blender Imperial

This concludes today’s tutorial! In the next tutorial we will talk about the following topics:

  • Visco temperature conversion

  • LPG/NGL calculation – liquid

  • LPG/NGL calculation – vapour

If you are interested in getting OilcalcsPro, the latest version of OilcalcsPro For Desktop can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

OilcalcsPro for desktop 101 – Part 2

In our last post concerning OilcalcsPro for desktop 101 we discussed the settings, and the impact of the choice between SI Metric and Imperial settings.

We also discussed the drop down boxes for density and volume, and showed an example of the reverse calculation going from weight to observed volume and we briefly mentioned the inline conversion that can be done using the density drop down box.

Today we will have a look at the following subjects:

  • Using pressure and thermal expansion coefficient inputs

  • The different oil types

  • Converting between different density units

  • Some real life calculation examples

The examples here are based on working with the latest version as of 16th January 2016 (version 1.0.2.0). The latest version of OilcalcsPro can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

So, lets get started and have a look at the remaining drop down boxes:

The temperature drop down box: this box has only two entries: deg C and deg F. If the temperature field contains a value, it will automatically be converted when you select the other temperature unit, e.g. if the temperature field contains a value of 32.6 with the temperature unit set at deg C, after selecting deg F the value in the temperature field will show 90.68.

The pressure unit drop down box: when using the 2004 tables, you can enter an observed pressure in either psi, kPa or Bar. This pressure could be for example the pressure in the pipeline where the liquid is being transported. You can find out more in detail about the calculations used by the 2004 tables in an earlier post on this blog under the title “ASTM Petroleum table 54 version 2004 and its implementation Part 1”. For table 6 a similar approach is used.

Just like with the temperature drop down box, if the pressure field contains a value, it will be converted automatically when you select a different pressure unit in the drop down box. For example if the pressure field contains a value of 1 Bar, if you then select psi, the new value shown will be 14.50.

When you use the 2004 version of the tables, regardless of whether you are using SI Metric or Imperial standards, the compressibility of the liquid is automatically calculated. If the pressure field does not contain a value the pressure is assumed to be zero. Compressibility is a measure of the relative volume change of a fluid as a response to a change in pressure, and it affects the volume correction factor of any liquid that is under a pressure higher than the atmospheric pressure.

It is for this reason also that the 2004 version of the tables do not anymore talk of a VCF or volume correction factor, but instead use the terms CTL (correction for the temperature of a liquid) and CPL (correction for the pressure of a liquid), and the combined term CTPL. Obviously for atmospheric storage of fuel oil, crude and lub oils, only the CTL needs to be taken in consideration, but for liquids under pressurized storage, or liquids being transported in pipelines under pressure the CPL has a significant impact on the correction factor.

The drop down box for the thermal expansion coefficient:

For crude oil, products and lubricating oils the thermal expansion coefficient is calculated using the density and three factors (K0, K1 and K2, which depend primarily on the oil type and in the case of Products also depend on the density) as input values:

alpha60

The CTL in turn is calculated using the thermal expansion coefficient and the temperature difference between actual temperature and base temperature.

For Special Applications such as denatured ethanol, anhydrous isopropyl, acetone and various other liquids, the thermal expansion coefficient cannot be calculated accurately using the aforementioned formula. Instead, these liquids have been submitted to certain tests in a laboratory which enable the testing facility to establish the coefficient accurately.

When dealing with such products, the manufacturer / supplier of the liquid provides a certificate that states the correct thermal expansion coefficient, if it is not listed publicly. For calculating a volume corrected to 15°C (or 60°F when using Imperial tables) you simply need to enter the actual temperature and the thermal expansion coefficient. For calculating weights you obviously also need to enter the density or API.

The 2004 standards use a thermal expansion coefficient expressed in 1/deg Celsius for SI Metric tables and 1/deg Fahrenheit for Imperial tables, but in OilcalcsPro you can enter either as long as you chose the correct unit belonging to the value that you’ve been given.

Just like the drop down boxes for density, temperature and pressure, changing the selected unit will cause the application to convert the existing value in the thermal expansion coefficient field to the newly selected unit.

The oil type drop down box: choosing between Crude oil, Products, Special Applications, Lub oil and LPG/NGL.

By selecting a certain oil type you are basically telling the application which table to use and which section: if you are using SI Metric standards and you select Crude Oil, the application will use table 54A. If on the other hand you are using Imperial standards the application will use table 6A in that case.

Likewise when you select Products, the application will use either table 54B or 6B depending on whether have chosen to use SI Metric or Imperial standards in the settings screen, and the same goes for Special Applications (table 54C or 6C) and Luboils (table 54D or 6D).

When you select LPG/NGL, the scenario is slightly more complicated: when using density 15, the application will use table 54E, if you are using SI Metric standards. If you are using Imperial standards, the application will use table 24E, after internally converting the used density format to relative density.

When using the other density units and working with the SI Metric standard as per your settings (please note that API is not available as a unit for LPG/NGL), the density is internally converted to density at 15°C, GSV is displayed in M³ at 15°C and weights are calculated using this GSV and the internally converted density at 15°C. When using density at 20°C however, this internal conversion is not done, and GSV is displayed in M³ at 20°C and weights are calculated using this GSV and density at 20°C.

When working with the Imperial standard however, all density units are internally converted to relative density, GSV is displayed in M³ at 60°F and weights are calculated using this GSV and the internally converted relative density.

Converting between different density units:

OilcalcsPro offers inline conversion between all available density units, taking into consideration whether you are using the 1980 version or 2004 version standards. It should be noted here that the 1980 version standards do not accommodate API values below zero, while the 2004 version standards do.

For converting an observed density to any other unit, you need to enter also a temperature value, otherwise the density field will remain empty when you select the new unit. As mentioned above, converting the density has no impact on the results except when converting to / from density 20 and using SI Metric standards. When using the Imperial standard, all densities are internally converted to relative density so converting the density has no impact on the results, although you may seem minor differences when converting back and forth between for example API and relative density as a result of rounding errors.

Real life calculation examples:

To get a feel for how the calculator works, let us carry out a few examples of practical problems.

1. Using table 54A – crude oil:

Assuming that we have orders to load 2 MB of Murban Crude, API = 40.1 and load temperature  = 89°F. Our principal has asked to let him know how much we can actually load in Bbls, Metric tons air and vac, and Long tons. The available 98% tank capacity of our vessel is 314,216 M³.

First, let us make sure that our settings are in sync: use 2004 version tables, use SI Metric standard, and use Table 56 for the conversion between Mtons in air and vac.

Next, in our calculator screen select crude in the oil type drop down, select ‘API60’ in the density drop down, enter 40.1 in the density field, and select ‘deg F’ in the temperature drop down, enter 89 in the temperature field. Check to make sure that the volume unit selected is ‘GOV M³’ and enter 314216 in the volume field.

In our results display we will now see the following figures:

– GOV(M³)          : 314,216.000

– GSV(M³-15°C): 309,458.770

– MT Vac             : 255,055.918

– MT Air              : 254,722.990

– LTons               : 250,700.03

– Bbls                   : 1,947,411 (These are Bbls at 60°F)

– US Gallons      : 81,791,262

Please note that for some users (such as from Netherlands, Germany etc) decimal dot and comma are swapped.

You can see in the above example that the vessel can only load slightly under the requirement of 2 MB, namely 1.947 MB.

2. Using table 6B – products:

A foreign vessel arrives in the US with a cargo of Jet A-1, with a density of 795.2 and a temperature of 17.6°C. The attending cargo surveyor must gauge the vessel and produce an arrival ullage report using Imperial units. Demonstrate for one cargo tank (no.1 C) how this is done: observed volume is 8,592.415 M³. Average temperature in this tank is 17.6°C.

Once again, let us make sure that our settings are in sync: use 2004 version tables, use Imperial standard, and the setting for Table 56 is immaterial in this case.

Next, in our calculator screen select products in the oil type drop down, select ‘dens15’ in the density drop down, enter 795.2 in the density field, and select ‘deg C’ in the temperature drop down, enter 17.6 in the temperature field. Check to make sure that the volume unit selected is ‘GOV M³’ and enter 8,592.415 in the volume field.

In our results display we will now see the following figures:

– GOV(Bbls)        : 54,045

– GSV(M³-60°F): 8,575.832

– MT Vac              : 6,815.957

– MT Air               : 6,806.693

– LTons                 : 6,699.19

– Bbls                     : 53,940 (These are Bbls at 60°F)

– US Gallons        : 2,265,480

Well, this brings us to the end of today’s tutorial. In the next tutorial we will cover the following subjects:

  • More calculations using the main calculator

  • Fuel Blending – two components

  • Fuel density after blending

  • The visco blender

If you are interested in obtaining a copy of OilcalcsPro, the latest version of OilcalcsPro can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

OilcalcsPro for Desktop – automatic updating and other improvements

Based on the latest feedback from users, as well as the result of our in-house review process, we have made the following additional changes and  improvements to the application:

– Automatic updating: the application now has a new setting, which will check for the availability of an updated version. If an update exists, the application informs the user, and you can then download the update from the about screen. The following screenshots show the process:

When the program starts the first time, it automatically checks for an available update: (This can be changed in settings to not check for updates):

Download available

Download available

If an update is available you can download it from the ‘About’ screen by clicking the ‘Check for updates’ button; if an update is available the application will ask you if you want to download, otherwise it will tell you the application is up to date:

Download latest version

Download latest version

Once you click ‘Yes’, the download starts:

Downloading update

Downloading update

When finished downloading, the ‘download completed’ message will pop up:

Download completed

Download completed

Once downloading is completed, you can close OilcalcsPro, unzip the downloaded update file, and copy the contents over the existing files in your installed location. NOTE: If you have data in the viscoblender database that you wish to keep, then do not copy the “oilcalcsDB.db” file. This file contains your viscoblender data.

– Improved consistency in calculating weights and volumes for LPG/NGL: previously it was not really obvious how weights and volumes for LPG/NGL were calculated when using Imperial standards, and when entering a quantity not being an observed volume in M³. This has now been standardized.

– Improved consistency in calculating weights and volumes for all oil types when entering density 15°C instead of API etc:

  • When using Imperial standards, all non API density values are converted to relative density at 60°F; this means that the CTL as displayed is the CTL corresponding to the converted relative density using Imperial standards. All weights and volumes are then calculated using the converted relative density and the corresponding CTL. Also the GOV is shown in Bbls, and the GSV is shown in M³ at 60°F, regardless of which unit is used in the volume field.

  • When using SI Metric standards, API, relative density and observed density are internally converted to density at 15ºC, GOV is shown in M³ and GSV is shown in M³ at 15°C. If the density unit is density at 20°C however, the GSV is shown in M³ at 20°C.

The new version of OilcalcsPro can be downloaded here. From now on, updates will still be announced in our blog, but if you keep the setting ‘Check for update on start’ selected (requires internet connection), the application will automatically check for updates:

New settings screen

New settings screen

OilcalcsPro for desktop 101 – Part 1

Having released OilcalcsPro for desktop just a few days ago, we thought it would be handy for new users to have a reference tutorial at hand, in the absence of a full user manual. Although the vast majority of functionality in the desktop version is identical to the way things work in the Android and iPhone app, there are a few small differences here and there.

Also the number of possible calculations that you can carry out in the calculator screen are numerous and are certainly worthy of an in-depth explanation with real life worked examples.

This tutorial will consist of several parts, since explaining everything in one go it would be impossible to keep the reader’s attention long enough to reach the bottom of the page….:)

If you don’t have a copy of the application, OilcalcsPro can be downloaded here.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

So here we are, at part 1 of this 101 guide, and let us start with briefly explaining the ‘Settings’ screen:

Settings screen

Settings screen

In the settings screen, the user can select his/her preferences for the following items:

  • Whether to use the 1980 tables or the 2004 tables.

  • Whether to perform calculations using the SI Metric system, or the Imperial system.

  • Whether to calculate metric tons in air using table 56 or by deducting 11 points from density in vacuo (this obviously only applies to the SI Metric system.

  • The number of decimals to use for rounding of CTL, GSV, metric tons, Gallons and Barrels

The choice between 1980 and 2004 tables is clear enough and speaks for itself, but there is one thing that may not be immediately obvious: when the user selects the 1980 tables, the CTL decimal rounding is automatically set to 4 decimals, whereas if the user selects the 2004 tables this rounding is set automatically to 5 decimals.

The user can however override this setting after choosing the table version, by simply selecting the desired rounding for the CTL after selecting the table version.

If you are wondering why we included the 1980 tables, when in the majority of countries the 2004 implementation has been adopted: because the API standard is a voluntary one, the only requirement in using a certain standard is that all involved parties should agree on which standard to use. So as long as buyer and seller agree to use the 1980 version tables, there is no problem. In countries such as Singapore the 1980 standard is until now in use, and adopting the 2004 standard is only now beginning to take place there.

The choice between using the SI Metric system and the Imperial system tells the application whether to use table 6A to calculate the VCF (or CTL as it is called nowadays) for a quantity of Crude oil, or to use table 54A to calculate, and the same goes for calculating Products, Lubrication oils and Special Applications. It should be noted here that when calculating LPG/NGL, only SI Metric calculations are available

This choice also tells the application whether to use Imperial units (i.e. API, Bbls and degrees Fahrenheit) or use Metric units (i.e. density at 15°C, M³ and degrees Celsius) in the various utilities. We will talk about that in detail when we discuss each utility.

The choice between using table 56 and using a not so accurate alternative of subtracting 11 points from the density in vacuo may seem a peculiar addition, considering that in most European countries, the United States and a number of countries in Asia, table 56 is used for the conversion from metric tons in vacuo to metric tons in air. There are however some countries such as for example Singapore, where it is common practice in the field to not use table 56 but instead the shortcut.

All of the above settings can be changed at any time, and any change will immediately be reflected in all utilities where the changes apply. For example in the main calculator screen, if we are calculating a quantity of fuel oil with a density of 990.1 at 15 °C in vacuo, at a temperature of 35.6 °C using SI Metric units, the CTL will be calculated using table 54B, and volumes and weights will be displayed accordingly.

If we then head to the settings screen and change to Imperial units, we will see that the displayed output now has changed:  the CTL has changed from 0.98590 to 0.98627; the density of 990.1 has been converted to an API of 11.33; the temperature has been converted from 35.6 °C to 96.08 °F, and obviously GSV and weights have changed slightly due to the change in CTL. We can change back the API, which will be then converted to 990.1 if we select density at 15 °C, and we could change back the temperature as well to degrees Celsius, but you will see that these two changes will not have any effect on the displayed results.

Now, before we start exploring the main calculator screen, let us ascertain that in the settings screen the various options have been set as outlined below, so that you can follow the examples using your copy of OilcalcsPro:

  • Select SI Metric Units

  • Select the 2004 tables

  • Select using table 56

  • Leave all decimal roundings at their default values

Having done that, we can head over to the main calculator screen to explore the various options and possibilities:

Main Calculator screen

Main Calculator screen

First of all let us look at the various controls available on the screen: starting at the top of the screen, on the left hand side we find the entry field for density or API, followed by the entry field for volume, followed by the entry fields for temperature, pressure and thermal expansion coefficient.

Then, on the right hand side from the top down, we find drop down boxes for density, volume, temperature, pressure and thermal expansion coefficient units.

Below these two rows of controls you see the oil type selector, which lets you choose between Crude, Products, Special Applications, Luboils and LPG/NGL. Below that is the space for the results to be displayed and finally at the bottom we have three buttons: one for the various tools, one for the settings screen and one for the About screen.

Next we will discuss the drop down boxes:

The drop down box for density: this box lets you choose the density unit, either:

  • Density at 15°C

  • API at 60°F

  • Relative density (formerly known as specific gravity) at 60°F

  • Density at 20°C

  • Observed density

If the density field contains a value and you select a different density unit, the application will convert the original unit to the newly selected one. For example, if our density field contains a value of 990.1 and density 15 is selected, if we then select API, the new value showing in the density field will be 11.33.

If you wish to convert an observed density to any of the other units, then you need to enter a temperature as well, before selecting a new density unit: first select “Obs.dens” from the drop down list, then enter your observed density and temperature; lets assume that the observed density is 970 and the observed temperature is 35.6; after selecting dens15, the new value showing in the density field will be 984 (assuming that Products is selected as oil type since the outcome of this conversion is oil type dependent).

One important note should be made here: when using API, relative density and observed density, the used density unit is converted to density at 15°C, and GSV is displayed as M³ at 15°C (when using SI Metric units in settings). When using density at 20°C however, GSV is calculated as M³ at 20°C (when using SI Metric units in settings). If you want to show GSV at 15°C, then you need to convert the dens20 first to dens15.

When using Imperial settings, GSV is always displayed in Bbls at 60°F. The reason for this difference between using SI Metric and Imperial settings is that in some places (notably oil terminals in Russia) a density at 20°C is used instead of 15°C, and GSV will be calculated also at 20°C. By implementing this differentiation the user can choose more flexibly how he wants his units to be calculated and displayed.

In the application there was a bug with this, as the volume was indicated as M³ at 15°C when it should read M³ at 20°C. The volume was however calculated correctly at 20°C. This has been corrected in the latest update, which can be downloaded here.

The drop down box for volume: this box lets you choose not only the volume unit, it also lets you select metric tons or long tons as input unit. This means that you can reverse calculate the quantity M³ at observed temperature that is occupied by a weight of 1500 Mtons in air for example. You can choose as input unit:

  • gross observed M³

  • gross standard volume in M³ at 15°C or 60°F, depending on whether you are using SI Metric of Imperial settings

  •  gross observed Bbls

  • gross standard volume in Bbls at 60°F

  • Metric tons in air

  • Metric tons in vacuo

  • Long tons

  • Gallons at 60°F

To illustrate this with an example, let us assume the following situation: a shore tank is nominated to receive a cargo of 12,000 Mtons (in air) Jet A-1 with a density of 795 and an actual temperature of 22°C. The available space in the shore tank is 15,000 M³. Prior to receiving, the logistics department needs to check if the amount of 12,000 will fit in the tank.

Solution: First select ‘Product’ from the oil type drop down; after entering a dens15 of 795, a temperature of 22°C and a volume of 12,000, select ‘MT Air’ from the volume unit drop down. At a weight in air of 12,000 Mtons, the gross observed volume shows as 15,215.294 M³, which exceeds the maximum volume of the shore tank.

Here ends part 1 of this tutorial. We still have quite a bit of ground to cover in the main calculator screen, and part two of OilcalcsPro 101 will deal with the following topics:

  • Using pressure and thermal expansion coefficient inputs

  • Converting between different density units

  • The different oil types

If you are interested in following the examples, OilcalcsPro can be downloaded here. Without registering, the application can be used fully functional for 15 days. Once the demo period expires, most of the functionality becomes disabled and you then need to register if you want to continue using all functions in the application.

If you want to convert the demo version to the permanent pro version, buy a license code voucher here: Goto Paypal

OilcalcsPro for Desktop – important update

Following the launch of OilcalcsPro we received feedback from a number of users, based on which we made various changes and improvements on the application.

Update: latest version uploaded on 12th January 2016.

The updated version has proper number format support for all non-US based windows versions now, this was one of the major problems with the original version; on for example computers with a Dutch version of windows, the numbers showing in some screens would be all wrong. Dutch, German and several other localisations of Windows swap the comma and the decimal point since in those countries the comma is used as the decimal point where as the decimal point is used as the thousands indicator.

Below two pictures show the difference between the US version and the Dutch version:

US version

US version

Dutch version

Dutch version

The application is available for Windows 7 and higher, and requires the .Net Framework 4 or higher installed.

Download link for OilcalcsProForDesktop:

Download from Dropbox

Buy license code voucher here: Goto Paypal

Note: please send an email to: mmc.mooring@gmail.com or ron.mooring@gmail.com if you do make a payment using paypal. Please include in your email both the Paypal transaction number and the serial number generated by OilcalcsPro. The way we have set up payment, it may take a day or two before we receive the confirmations into our account”.

Download link for OilcalcsProForDesktop: Download from Dropbox

Download link for .Net 4.5: Offline .Net V 4.5 installer on Microsoft.com 

Download link for .Net 4.0: Offline .Net V4 installer on Microsoft.com

OilcalcsPro for Desktop: an app for windows desktop users

We are pleased to announce the launch of a new app today – OilcalcsPro for Desktop: a desktop version of the OilcalcsPro app for Android / Oilcalcs app for iPhone.

The application is available for Windows 7 and higher, and requires the .Net Framework 4 or higher installed.

Update 1: latest version uploaded on 12th January 2016.

Update 2: a few users noted that the app starts up using the 1980 version of the ASTM tables. In order to change that, just go to the ‘Settings’ screen, and select ‘2004 tables’.

Update 3: please send an email to: mmc.mooring@gmail.com or ron.mooring@gmail.com if you do make a payment using paypal. Please include in your email both the Paypal transaction number and the serial number generated by OilcalcsPro. The way we have set up payment, it may take a day or two before we receive the confirmations into our account”.

Update 4: we’ve noticed that for certain languages, such as Dutch, the number format does not respond as expected and results in errors in some screens (such as the Blend Two Components screen). We are working on a solution for this and will release an update within the next 2 or 3 days.

Update 5: number formatting has now been fixed and should work for all languages. Please download the latest version of OilcalcsPro using the link below.

Download link for OilcalcsProForDesktop:

Download from Dropbox

Buy license code voucher here: Goto Paypal

Here are some screenshots of the application:

Main calculator

Main calculator

The main calculator calculates for Crude, Product, Luboil, Special Applications (such as denatured Ethanol), and LPG/NGL, just like the Android and iPhone apps do. The drop down list next to the volume entry can be used to select not only volumes but also metric tons, long tons etc in order to calculate reversely, from weight to observed volume etc.

All other utilities

All other utilities (Tools)

Settings screen

Settings screen

Just like the Android / iPhone counterparts, the application gives access to both the 1980 and 2004 versions of the ASTM tables, as well as to calculations for SI Metric (i.e. table 53, 54 etc) and Imperial (i.e. table 6, 24 etc).

LPG density calculator

LPG density calculator

The LPG density calculator uses the Francis formula to calculate density, based on the amount of 5 possible constituents, vapour and liquid temperature and vapour pressure.

Oil API / density conversions

Oil API / density conversions

The oil converter gives full access to the 2004 version of tables 5(A/B/D), 6(A/B/C/D), 23(A/B/D), 24(A/B/C/D), 53(A/B/D), 54(A/B/C/D), 59(A/B/D) and 60(A/B/C/D). It also does inline conversion between API / relative density / density at 15C / density at 20C and observed density.

LPG/NGL density conversions

LPG/NGL density conversions

The LPG/NGL density converter gives access to table 53E and 59E, for converting an observed density to respectively density at 15C and 20C, and table 23E, for converting an observed density to relative density at 60F.

LPG/NGL vapour calculation

LPG/NGL vapour calculation

LPG/NGL density calculation

LPG/NGL liquid calculation

Visco, pourpoint, flashpoint and density blender

Visco, pourpoint, flashpoint and density blender

The visco blender can blend up to 10 components, which are stored inside a database for easy retrieval and editing. The blender calculates the resulting viscosity (in cSt), flash point, pour point and final density (or API) of the mix. The upper part of the blender contains a viscosity target calculator, which calculates the amount of two components of a certain viscosity to reach a target viscosity.

Density after blending

Density after blending

The fuel blender comes in two variations: the one above calculates the final density based on an existing quantity and adding a second quantity with a given density, and a final volume and temperature.

Blending 2 components and calculate shrinkage

Blending 2 components and calculate shrinkage, which to load first

The second blender is great for two things: to calculate the amount of shrinkage when blending two components, and to establish which component to load first based on their density (or API) and actual temperature. Especially when densities do not differ all that much, it is not immediately apparent which component to load first, because if the temperature of the high density component is sufficiently higher than the temperature of the other component, you will see that the lower density component must be loaded first in order to achieve proper blending.

Visco-Temp Converter

Visco-Temp Converter

The visco-temp converter can graph viscosity against temperature in two ways; either using the so-called V50 formula, which requires only one density and one temperature as input, and the other one using the Walther equation, which needs two viscosities and two temperatures to produce a graph. Temperatures can be entered in either degrees Celsius or Fahrenheit (this goes for most of the screens), and the maximum viscosity to be displayed can be selected. The graph automatically switches from one to the other when you enter any data in the related boxes.

Download link for OilcalcsProForDesktop: Download from Dropbox

Download link for .Net 4.5: Offline .Net V 4.5 installer on Microsoft.com 

Download link for .Net 4.0: Offline .Net V4 installer on Microsoft.com

Download itself is free, and gives you a demo version that fully functions for 15 days. If you wish to continue using it after that, you will need to buy a license code voucher (USD 9.99), using Paypal or credit card through Paypal.

The license code is indefinitely valid, for one machine. To buy a license code, you can click the Paypal link below, this will take you to a Paypal invoice page. In the invoice page, please make sure to provide your email address and the serial number as generated by OilcalcsPro.

Alternatively you can send an email to mmc.mooring@gmail.com, stating the serial number and your Paypal transaction reference number. Upon receiving these, the license code will be sent to you. Once you enter the license code in the application, registration is complete.

Buy license code voucher here: Goto Paypal