JPH0457967B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flow rate measuring device installed at oil supply sites such as oil depots and oil refineries.

Mechanical and electrical types are used as flow rate measuring devices having a temperature correction function. Mechanical systems do not require explosion-proof measures, but since the bellows use gears, minute temperature changes cannot be accurately transmitted, making it impossible to accurately measure the flow rate with temperature compensation.

In addition, in the case of an electric type, the temperature correction of the flow rate is accurate, but since electricity is used, conventionally, to measure the flow rate of flammable liquids such as petroleum, the flow rate measured with a flow meter and a flow meter at the refueling site is conventional. A flow rate pulse transmitter that sends a flow rate pulse based on the temperature and a temperature sensor that detects the temperature of the fluid are installed, and a control device, specific gravity setting device, instrumental difference adjuster, and integration after temperature correction are installed in an office far from the refueling site. A flow rate indicator, etc. is installed.

The outline of its operation is as follows.

A volume conversion coefficient table defined by JIS K-2249 is stored in the control device. Then, the specific gravity of the oil to be measured is input to the control device, and the flow rate of the flowmeter is actually measured and an instrumental error correction value is input to the control device.

Next, when the oil is poured, the temperature signal detected by the temperature sensor is input to the control device, and the converted volume is selected from the volume conversion coefficient table based on the temperature signal and the specific gravity input earlier, and the temperature correction coefficient is calculated. Ru.

Then, the flow rate signal from the flow rate pulse transmitter of the flow meter is corrected by the previously input instrumental error correction value, and the temperature-corrected flow rate is calculated and displayed from that value and the temperature correction coefficient. etc. will be communicated to.

By the way, as mentioned above, the conventional electric flow rate measuring device with temperature correction function has the control device etc. installed in the office, so it may be somewhat large and does not have an explosion-proof structure. Good too.
For this reason, the temperature display from the temperature sensor, the display of the instrumental error correction value, the display of the set specific gravity, the display of the calculated temperature correction coefficient, etc., were displayed using a CRT or a separate display meter. Incidentally, specific gravity setting and instrumental error adjustment are performed using a ten-key switch or the like.

However, in the case of the conventional method in which the control device is installed in the office, the flow rate signal from the flow pulse transmitter of the flow meter installed at the refueling site and the temperature signal from the temperature sensor are transmitted to the control device installed in the office using cables etc. There were problems in that the cable had to be connected to a cable, which required troublesome cable construction, and it was susceptible to noise.

For example, Japanese Utility Model Application Publication No. 56-10810 discloses a flow meter that calculates the flow rate of a fluid by an integration coefficient based on the number of revolutions of an impeller. However, although such known techniques can correct instrumental errors, they cannot correct temperature based on temperature. For example, JP-A-57-
Japanese Patent No. 158521 discloses a technique for correcting a gas to a reference volume at a reference pressure and a reference temperature. However, in the case of gas, there is no problem because the temperature and pressure change substantially proportionally, but in the case of oil handled at oil depots and oil refineries, the specific gravity varies depending on the oil type, and the temperature correction coefficient is Therefore, the above-mentioned known technology cannot be applied.

Furthermore, as described above, JIS K-2249 provides a volume conversion coefficient table based on the specific gravity of oil, but it is difficult to specify data for oil with a specific gravity at the installation site.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a flow rate measuring device in which a control device can be installed at a refueling site and data can be easily specified.

The flow rate measuring device according to the present invention includes a first display meter that displays the cumulative flow rate and a second display meter that displays stored specific gravity and instrumental error correction value data in an explosion-proof box that can be attached to the flow meter main body. The flow rate transmitter, the flow rate signal of the flow rate transmitter, the temperature signal from the temperature measuring device, and the stored volume conversion coefficient, specific gravity, and instrumental error correction value are stored in an explosion-proof box so that they can be viewed from the outside. Calculate the flow rate with instrumental error correction and temperature correction, and calculate the integrated flow rate value as the first
a control device for displaying on a second display meter, an input means for inputting a hydrometer difference correction value, and a data specifying means for specifying data to be displayed on a second display meter,
The input means and the data designation means are provided on the outer surface of the explosion-proof box, and the input means and data designation means are covered with a removable first lid. A second lid is provided at a location opposite to the designating means.

Therefore, when performing flow rate measurement work, first, the specific gravity of the liquid to be measured and the instrumental error correction value are input using the operator of the input means. These data are displayed on the second display, and selection of the data is performed using the operator of the data designation means. The display on this second indicator can be selectively displayed by data designating means, for example, a push button.

According to the purpose of the present invention, since the control device is installed at the refueling site, the control device must be housed in an explosion-proof box. To this end, according to the present invention, the first and second indicators are provided at positions that are visible from outside the explosion-proof box. Furthermore, explosion-proof boxes are made to be able to be opened and closed for internal inspection and maintenance, but opening and closing them is quite a difficult task. For this purpose, the input means operator and the data designation means operator which must be operated as necessary can be operated from outside the explosion-proof box, and are covered with a first lid that is relatively easy to attach and detach. . Therefore, by removing the first lid, the outside of the explosion-proof box can be operated, and furthermore, tampering can be prevented. Since the operator of the data specifying means is operated relatively often, it can be operated by removing the easily attachable and detachable second cover. As described above, according to the present invention, the operability of the operator can be improved and tampering can be prevented without impairing the explosion-proof function of the explosion-proof box.

Therefore, during normal operation, the correct flow rate can be displayed on the first display meter by the signal from the flow rate transmitter based on the input specific gravity and instrumental error correction value.

In this way, the control device can be installed at the refueling site, which solves the problem of noise, eliminates the need for cable work, and improves safety due to the explosion-proof box.
This can be achieved at the same time as improving operability.

In carrying out the present invention, it is preferable to use a rotary switch as the input means and a memory value change button switch as the data designation means.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a block diagram of each component of a flow rate measuring device embodying the present invention. A connecting pipe 1C equipped with a flow rate measuring device (to be described later) is flange-connected between 1B, and the connecting pipe 1C is equipped with a flowmeter 2 for measuring the flow rate of oil flowing inside the pipe and a temperature measuring device for measuring the temperature of the oil. A temperature sensor 3 is provided. A flow rate pulse transmitter 4 which is a flow rate signal transmitter driven by the flow meter 2 is provided, and the flow rate signal from the flow rate pulse transmitter 4 is inputted to the control device 5 as a pulse signal. Further, a temperature signal from the temperature sensor 3 is similarly input to the control device 5.

As mentioned above, the volume conversion coefficient table defined by JISK-2249 is stored in the control device 5 in advance. Further, as will be described later, the specific gravity of the oil measured by the setting dials 6 and 7 and the instrumental error correction value of the flow meter are inputted to the control device 5, respectively. When the oil flows, a converted volume is selected from a volume conversion coefficient table based on the temperature signal from the temperature sensor 3 and the specific gravity input earlier, and a temperature correction coefficient is calculated by the control device 5. Further, the flow rate signal from the flow rate pulse transmitter 4 is corrected by the previously input instrumental error correction value, and the temperature-corrected flow rate is calculated by the control device 5 using that value and the temperature correction coefficient, and the integrated flow rate is displayed on the display meter 9. The corrected pulses are then output to a batch counter (not shown) or the like. Further, various memory values such as set specific gravity and instrumental error correction value set using the setting dial are displayed on a memory value display meter 10 by a memory value change button 8, which will be described later.

Note that if it is not necessary to constantly display the cumulative flow rate, the cumulative flow rate may be displayed on the display meter 10 by pressing and switching the button 8 without using the display meter 9.

The flow rate pulse transmitter 4, the control device 5, and the display meters 9 and 10 are housed in an explosion-proof box 11.

When implementing the present invention, the following points will be taken into consideration.

(1) Since it is installed at the liquid supply site, it should be made smaller. For this reason, (a) various display meters are virtually shared.

(b) Turn the specific gravity setting dial to 6 as shown in Figure 2.
The specific gravity can be set up to four digits using the three specific gravity setting dials 6A, 6B, and 6C. This flowmeter takes advantage of the fact that the oil (crude oil, refined oil, LPG, etc.) measured by this flowmeter does not have a specific gravity of 1.2 or higher, nor does it have a specific gravity of 0.5 or lower. In addition, setting dials 6A, 6B,
The switch set by 6C uses a general rotary switch 16 with 10 contacts.

In order to be able to set up to four digits with the three specific gravity setting dials, the setting dial 6A, which is 1/10, is used as shown in the table below. "0" is "1.0", "1" is "1.1", "5"
is "0.5", "6" is "0.6", "9" is "0.9", and the underlined numbers are displayed.

Verification Table 0 1.0 0.1 0.1 2 1.2 0.2 3 1.3 4 1.4 0.4 5 1.5 6 1.6 0.6 7 1.7 0.7 8 1.8 9 1.9 0.9 (C) As shown in the figure, it is one of the dials 7.

This instrumental error adjustment dial 7 is a normal one with 10 contacts, and in order to widen the adjustment range of the instrumental error, it is made fine where the instrumental error is small and coarse where the instrumental error is large. As a result, a flowmeter with good accuracy will have its instrumental error corrected with good accuracy, and a flowmeter with poor accuracy will be corrected in a rather poor manner.

(d) The display change switch for displaying various memory values on the display meter 10 is one of the switches 17, which is opened and closed by the push button 8, as shown in FIG.
The control device counts the number of presses and displays various memory values.

(2) Measures should be taken to prevent setting values from being changed due to mischief or erroneous operation on site. For this reason, cover each setting dial with a lid 19 and seal it.

FIGS. 3 and 4 show the external shape of a flow rate measuring device embodying the present invention, and a flow meter 2 (FIG. 1) is provided in a connecting pipe 1C that is flange-connected between liquid supply pipes 1A and 1B. , the flow meter 2 includes a display meter 12 indicating the flow rate before correction and a temperature sensor 3.
is provided, and the temperature sensor 3 is connected to the connection part 1.
It is equipped with 4. Further, an explosion-proof box 11 is attached to the flowmeter 2, and a flow rate pulse transmitter 4 operated by the flowmeter 2 and a control device 5 equipped with a microcomputer that performs calculations in the manner described above are installed in the box. ing. Control device 5
are the specific gravity setting dials 6A, 6 shown in Fig. 2.
B, 6C (hereinafter simply indicated by the reference numeral 6 when there is no need to distinguish between them), an instrumental error adjustment dial 7, a display change button 8 for various memory values (setting specific gravity, instrumental error correction values, etc.) on the display meter 10, and A corrected integrated flow rate indicator 9 and a memory numerical value indicator 10 are connected. Then, the rotary switches 16, 16', 1 for the flow rate pulse transmitter 4, the control device 5, the specific gravity setting dial 6, and the instrumental difference adjustment dial 7
6″, 16, memory value change button switch 1
7, a flow rate indicator 9, a memory numerical indicator 10, etc. are housed in an explosion-proof box 11.

Fig. 5 shows an example of a manner in which the specific gravity setting dial 6, instrumental difference adjustment dial 7, and memory value change button 8 are covered and sealed. The bolt 20 is sealed with a wire 15. In addition, a hole is drilled in the lid portion corresponding to the memory value change button 8, and a screw lid 18 is inserted into the hole.
is screwed in, and its screw cap 18 is not sealed. Therefore, when displaying various memory values, without removing the lid 17, the screw lid 1
8 can be removed to display the memory value.

Therefore, the specific gravity setting dials 6A, 6B, and 6C and the instrumental difference adjustment dial 7 are set in advance during flow measurement work. For example, specific gravity is 1.057
In the case of heavy oil, the setting dial 6A should be set to "0", the setting dial 6B to "5", and the setting dial 6C to "7". Also, when setting oil with a specific gravity of 0.728, set the setting dial 6A to "7" and set the setting dial 6B.
and the setting dial 6C to "8". As shown in the previous table, the settings dial 6A has scales of "2", "3", and "4" that are not normally used. The reason is that the specific gravity is 1.2 or more and
This is because oil with a value of 0.5 or less cannot be used practically.

In this way, the specific gravity can be set to the 1/1000th digit using the three setting dials.

The instrumental error adjustment dial 7 has a log scale, and by doing so, as described above, areas where the instrumental error is small are made fine and areas where the instrumental error is large are made coarse. This is also set after detecting the instrumental error with the reference meter. Note that the X mark in the figure is a contact point for the dummy pulse.

After setting each specific gravity setting dial and instrumental difference adjustment dial 7 in this way, close the lid 19,
Then, it is sealed with a wire 15 so that the set value cannot be changed. These set values and other memory values are displayed on the display meter 10 by pressing the button 8. For example, if you press this button 8 once, the set specific gravity will be displayed, if you press it once again, the set value of the instrumental difference will be displayed, if you press it once again, other memory values will be displayed, and if you press it several times, it will return to the original value. It's summery. This button 8 can be easily operated by removing the lid 18.

The switches 16 and 17 are located in the explosion-proof box 11, and the dial 6, which is the actuator,
7. Button 8 is located outside box 11, so
Since they are provided outside the box 11 when setting them, there is no need to open the box 11 when setting them, and therefore there is no danger in performing the setting operations on site.

As explained above, the present invention receives signals from a flow rate signal transmitter of a flowmeter, a temperature measuring device that measures the temperature of a fluid, a flow signal transmitter, and a temperature measuring device, and converts the value into a flow rate at a predetermined temperature. The control device that performs the calculation is installed near the flow meter along with the display meter that displays the flow rate calculated by the control device.
There is no need for cable construction to reach the office as in the past, and noise problems can also be solved. Furthermore, since the flow rate signal transmitter and control device are housed in an explosion-proof box, there is no risk of fire occurring from these devices that use electricity.

[Brief explanation of the drawing]

FIG. 1 is a block piping and wiring diagram of a flow rate measuring device embodying the present invention. FIG. 2 is a front view of a specific gravity setting dial, an instrumental difference adjustment dial, and a memory value changing button used in a flow rate measuring device embodying the present invention. 3 and 4 are external views of a flow rate measuring device embodying the present invention, with FIG. 3 being a front view and FIG. 4 being a side view. FIG. 5 is a longitudinal sectional view partially showing a side view of a lid covering a specific gravity setting dial, an instrumental difference adjustment dial, and a memory value changing button used in a flow rate measuring device according to an embodiment of the present invention. 1A, 1B...Oil supply pipe, 1C...Connection pipe, 2
...flow meter, 3 ... temperature sensor, 4 ... flow rate pulse transmitter, 5 ... control device, 6 ... specific gravity setting dial, 7 ... instrument difference adjustment dial, 8 ... memory value change button, 9 ... ...Flow rate display meter, 10...Various memory numerical display meter, 11...Explosion-proof box, 12...
A display meter that displays the operating status of the flowmeter.

Claims (1)

[Claims] 1. In an explosion-proof box that can be attached to the flowmeter body,
A first display meter that displays the cumulative flow rate and a second display meter that displays stored specific gravity and instrumental error correction value data are housed so as to be visible from the outside of the explosion-proof box, and the flow rate transmitter and , Calculate the flow rate with instrumental error correction and temperature correction using the flow rate signal from the flow rate transmitter, the temperature signal from the temperature measuring device, the stored volume conversion coefficient, specific gravity, and instrumental error correction value, and calculate the integrated flow rate value. A control device for displaying on a first display meter, an input means for inputting a hydrometer difference correction value, and a data specifying means for specifying data to be displayed on a second display meter are housed, and the explosion-proof box is provided on the outer surface thereof. An input means and an operator for the data designation means are respectively provided, the operator for the input means and the operator for the data designation means are covered with a removable first lid in an explosion-proof box, and the lid faces the data designation means. A flow rate measuring device characterized in that a second lid is provided at a location where the flow rate is measured.