In particular, the invention relates to a method and associated device for the control of delivery of metered amounts of temperature-sensitive hydrocarbons such as petroleum spirit.

Background of the Invention: Petroleum is sensitive to temperature inasmuch as its volume is dependent upon ambient temperature. The petroleum expands as temperature rises and therefore a smaller mass, with a resulting smaller energy content, is contained in a given volume. It has been shown that a temperature change of 2. 5°C will change the volume by 0.3%.

All transfers of petroleum between oil companies and all excise paid to government are made on the basis of volume corrected to the International Reference Temperature of 15°C. However, all retail and most wholesale sales at delivery are made without temperature correction.

At fuel loading terminals, complex computer-aided temperature measurement is made and a computer-determined volume is measured as expanded litres and a computer-corrected 15°C equivalent volume is calculated for the purposes of payment of excise.

Such equipment is very complex and costly and thus it is not practical to reproduce the equipment at the various points of delivery of the transported petroleum.

However, because temperature correction does not occur at that time, the customer receives hot (ie ambient temperature), expanded fuel. Any fuel"hot delivered" (i. e. above 15° C) will cool and shrink in underground storage tanks thus reducing the volume that can be resold.

There is a need for a simple method, and an associated device that is simple in its construction and operation, that can be used at the point of sale (i. e. delivery) of split deliveries of fuel to measure the temperature of delivered fuel and calculate a volume correction to account for the actual mass of fuel supplied.

The present invention seeks to meet this need.

Summary of the Invention: This invention accordingly provides a method comprising the steps of : at point of delivery of fluid hydrocarbon fuel by road tanker, interposing a temperature measuring device into a fluid delivery line ; recording temperature and volume of delivered fluid; measuring or calculating the density of the fluid; calculating a temperature-corrected volume of delivered fluid by reference to pre-determined temperature-correction coefficients.

The invention also provides a temperature-measuring device adapted for interposition in a fluid hydrocarbon fuel delivery line at point of delivery by road tanker comprising: a lumen in communication with fluid flow within the delivery line; a temperature probe within the lumen and located in the fluid stream;

means for observing or recording the temperature of the fluid in the fluid stream detected by the said probe.

Preferred Aspects of the Invention: It is preferred that the temperature measuring device includes a probe that measures the density of fluid in the fluid stream.

It is further preferred that the temperature measuring device includes a probe that measures the volume of fluid passing through the device.

In the method, it is preferred that the density of the fluid is determined by measurement. It is further preferred that the measurement of the density is achieved by use of the preferred device as described herein.

In order that the invention may be better understood, a preferred embodiment will now be described with reference to the accompanying drawings.

Description of the Views of the Drawings Figure 1 is a side view of a temperature measuring device according to the invention shown partly in section to illustrate the interior of the device.

Figures 2 to 5 are front, top, male-end and female-end views, respectively, of an alternative device according to the invention.

Detailed Description of the Invention A temperature measuring device according to the invention is illustrated in Figure 1. The device is shown partly in section to illustrate internal features.

The device comprises a hollow cylindrical body (1) having an industry standard cam lock male coupling (2) located at one end and a cam lock female coupling (3) located at the opposite end of the body. In an alternative embodiment of the device the cam lock fittings may be interchanged with industry standard threaded couplings.

Within the female coupling is located a seal (4) to make good the connection between the device and a mated surfaced of a fuel delivery line. The seal is completed by actuating the cam locks (5).

To the external surface of the body is welded or affixed a boss (8) and surrounding protective shroud (7). A hole is drilled through the boss and is threaded to accept a BSP/NPT sleeve or a thermometer body (9) of which a probe sensor (6) extends into the lumen of the body such that any fluid flowing over or past the sensor will cause a registration in the sensor which is translated as a temperature read out. The boss and protective shroud are oriented at an angle to the body so that the probe is in turn oriented at an angle downstream to the flow of fluid so that there is less force applied to the end of the probe.

The dial of the thermometer may be rotated or oriented for best viewing by an operator during use of the device and can be silicone filled to avoid damage.

In this embodiment of the device there is provided a second protective shroud (11) within which a second hole is drilled into the body and is threaded to accept a BSP/NPT sleeve or a volume measuring unit (10). The flow metering end (12) of the volume measuring unit protrudes into the lumen of the body so that fluid flowing through the device will be detected and recorded.

The device is designed to be intrinsically safe and electrically continuous to avoid generating sparks that could ignite hydrocarbon vapours. In addition, the device is fluid-tight and vapour-tight. Construction may be in aluminium or plastic by die- casting, extrusion or machining. The length of the device may be varied according to convenience as may the angle of the body to the end couplings.

As this device is simply an additional coupling attached to the delivery outlet of a road tanker, it does not raise any additional safety issues over and above those that are already addressed for split deliveries of fuel.

In another embodiment the invention provides a method for controlling the delivery of a temperature sensitive hydrocarbon fuel. The method is particularly adapted for use in determining the temperature correction and the derived volume of fuel delivered in split loads.

The method comprises the steps of : 1. the interposition of a portable or fixed temperature/volume/density and/or time measuring device into the gaseous and/or liquid petroleum product delivery and/or transport and/or storage system.

2. recording/storage of data; of the first observed/declared/calculated volume or temperature or time or density at the same time as taking temperature and measuring flow through volume.

3. the observance and recording of aspects of volume as effected by temperature and/or time and/or density.

4. the application of an operation on data, comparison to a standard reference, or a formula and/or factor to calculate the density as affected by temperature or application of time to the process of delivery/storage of petroleum product.

At the point of delivery, a road tanker is dipped, a temperature-measurement device according to an embodiment of the invention is attached to the tanker delivery hose or tanker tap or to an underground tank using an industry standard cam lock fitting.

In-line temperature measurements are taken at the same time as the tank volume is dipped or read off a supplier's docket or taken as a measured flow volume.

The action of the liquid or vapour fuel flowing over a sensor in the device will register temperature to an accuracy of +/-0. 5°C for an analogue meter or +/-0.1 °C for a digital meter. When fitted with a density-determining probe, the device will provide simultaneous density and temperature data.

Once the density of the delivered fuel has been determined by calculation and/or direct measurement, a temperature-corrected volume of fuel is determined by reference to pre-determined temperature-correction coefficients as published by the Standards Association of Australia (AS 2520-1981). The disclosure of the "Australian Standard for Petroleum Measurement Tables"is incorporated herein by reference.

The invention should be understood to embrace many further modifications and embodiments as will be readily apparent to persons skilled in the art and which will be deemed to reside within the broad scope and ambit of the invention, there having been set forth herein only the broad nature of the invention and a certain specific embodiment by way of example. In that regard, the disclosure in the associated Australian provisional patent application (number PQ6264) is incorporated herein by reference.