Then, the fluid must be drained to ensure the functionality of the meter. Figure 3: The preferred and non-preferred orientation for horizontal pipe installation. The orientation of the transducer holders in this case does not matter, as the possibility of fluid filling the upstream transducer holder is the same regardless of the orientation. In this case the transducer holders may be mounted in a position that suits space and access requirements.
If this is the chosen orientation, then the upstream transducer holder must be periodically checked for liquid accumulation and emptied, if necessary. Figure 4 shows the transducer holder orientations for a vertical pipe. A continuous drain system may be installed by leading the fluids back into the pipeline at a lower point of the flare stack.
Figure 4: Vertical flare boom with the transducer holders and transducers installed. The orientation of the transducers is irrelevant for installation on a vertical pipe run. Before installing the transducer holders on the pipe, the correct placement of the spot marks must be ensured. There are numerous ways this can be done. The first consideration is the location of where the spot marks are supposed to be placed. The first thing to do is to find the centerlines on the pipe.
Note that the centerlines are exactly opposite each other on the pipe, ref. Figure 6. Always ensure that the centerlines are placed accurately by measuring the distance between them, both on the upper and lower circumference. The measured lengths should be the same. Figure 7: Cold tapping — contour marker. If the pipe is horizontal, use the Curv-O-Mark contour marker to find the centerlines on each side of the pipe, ref.
Figure 7. Remember to turn the contour marker and set a second spot, to avoid problems in regards to misalignment of the grade scale. If the pipe is vertical or inclined at a certain angle, other means of finding the centerlines must be applied. Confer with the pipe fitter or welder, as they usually have the tools and experience needed to help you.
After the centerlines have been marked and their position has been verified, use the labeling band to mark a line around the pipe, placed at the first spot spot A , ref. Figure 8. Then, on the other side of the pipe, measure the distance to the second spot spot B. It is also a good idea to mark another line around the pipe at spot B, as this will help when placing transducer holder B.
Spot A Figure 8: Marking a line around the pipe using a marking band. Mark the hole for the sensors on the pipe wall following the inside rim of the transducer holder when they are mounted in the welding-jig. Repeat the procedure for the other transducer holder.
The holes can now be cut according to the marked line on the pipe-wall. After the holes are cut, ensure that the inner edges are grinded to be smooth, and beveled in the correct way, ref. Figure 9. Before the welding starts, the groove angle must be grinded on the holders.
Figure Figure Machined holder. Adjust the gap between the pipe and the transducer holder until it is correct. This is done to get a satisfactory welding connection. Figure As you raise the transducer holder, you must also move it backwards to keep the centering correct. When the transducer holders are grinded and the holes have been made, the welding-jig should be located in the right position and the transducer holder connected. The transducer holder can now be tacked to the pipe.
Usually, the welder will use three or four tacks. Ensure that there is enough space to insert the transducer. Fluenta recommends using the sighting tool to verify this. The tool should be able to be inserted without any friction or obstructions. The next step is to mount the second transducer holder. Be aware that as the welding is in progress, the transducer holders can be pulled off their angles by the welding process. Therefore, it is necessary to pay close attention during the welding, regularly checking the angles with the digital electronic level.
Figure Welding jig and transducer holder. Figure Transducer holder welded to the pipe. This activity needs to be carried out by a skilled welder as precision and accuracy is necessary to get the transducer holders welded into their right positions. Next step will be NDT and final approval of the welding. The weldingjigs can be dismounted when the transducer holders are properly connected to the pipe as shown in Figure There are two tools in a set, one fits tightly in each transducer holder.
Each of the tools has a hole in the center. This set of tools uses the path of light for verification like the first. The set comes with a pair of stop washers, shown in Figure The tool must penetrate the transducer holder to the same depth as the transducer.
This is shown in Figure This depth should be the same for the sighting tool. Measure from the narrow end of the sighting tool and tighten the stop washer at that position. Insert the sighting tool so that the stop washer is flush with the flange on the transducer holder, this is shown in Figure There is a groove in the head of this type of sighting tool shown in Figure Align one sighting tool with the pipe, and rotate the other until the light is visible.
Adjust the sensor holder so that the circle of light is seen as described below. Visual check Figure Look through the holes on the sighting tool. When the transducer holders are properly aligned and the sighting tools are inserted, it is possible to see a perfect circle of light when looking through the hole in one of the sighting tools, shown in Figure If there is not enough ambient light, it may be necessary to shine a light source through the hole in the opposite sighting tool.
Figure A bad alignment. When the welding of the transducer holders has been performed and the ball valves are mounted, connect the hot-tapping equipment to the 2" ball valve.
Open the ball valve and drill the hole. The hole should be as close to If possible, use a 49 mm drill and avoid sharp edges. The method is shown in the figure below. This is carried out on site during installation of the transducers due to the fact that the entire length is measured, including ball valves and gaskets. The transducer is thereafter positioned correctly. Figure The gas-proof measuring tool. When setting the insertion depth, remember that the retraction of the transducer means that the insertion depth should be reduced see Figure Figure Insertion depth.
The insertion depth green arrow must be reduced red arrow according to the angle of the transducer holder As a result of the reduced insertion depth, the distance between the transducer tips will increase see Figure The transducer tip distance is a parameter that directly affects the flow velocity calculations, therefore the transducer distance must be updated in the configuration of the flow computer.
When the transducers are retracted, the transducer distance will increase from the original distance red arrow in Figure 25 to the new transducer distance green arrow. This must be updated in the flow computer. The transducer distance must then be increased by 36mm 2x18mm in the flow computer configuration. The transducer distance must then be increased by If this is a first time installation, the transducer holder should be checked for liquid and drained prior to installation. Care must be taken to avoid any impact or friction to the ultrasonic sensor head.
Also, it must be ensured that the sensor casing is connected to protective earth. Verify that the installed ball valves are gas tight no gas leaks. This should be done by the on-site personnel - using a gas monitoring device. Measure and adjust the installation depth of each transducer, which is set by fastening the Alock lock-ring. Open the ball valve, and push the transducer all the way in, until meeting the A-lock locker ring.
Fasten the A-lock nut to the transducer packbox. FGM is condemned by a number of international treaties and conventions, as well as by national legislation in many countries. Similarly, defining it as a form of torture brings it under the rubric of the Convention against Torture and Other Cruel, Inhuman, or Degrading Treatment or Punishment. Moreover, since FGM is regarded as a traditional practice prejudicial to the health of children and is, in most cases, performed on minors, it violates the Convention on the Rights of the Child.
Available data from large-scale representative surveys show that the practice of FGM is highly concentrated in a swath of countries from the Atlantic coast to the Horn of Africa, in areas of the Middle East such as Iraq and Yemen and in some countries in Asia like Indonesia, with wide variations in prevalence.
The practice is almost universal in Somalia , Guinea and Djibouti , with levels around 90 per cent, while it affects no more than 1 per cent of girls and women in Cameroon and Uganda. However, FGM is a human rights issue that affects girls and women worldwide. Evidence suggests that FGM exists in places including Colombia [2] , India [3] , Malaysia [4] , Oman [5] , Saudi Arabia [6] and the United Arab Emirates [7] , with large variations in terms of the type performed, circumstances surrounding the practice and size of the affected population groups.
In these contexts, however, the available evidence comes from sometimes outdated small-scale studies or anecdotal accounts, and there are no representative data as yet on prevalence. The practice is also found in pockets of Europe and in Australia and North America which, for the last several decades, have been destinations for migrants from countries where the practice still occurs [8].
The highest levels of support can be found in Mali , Sierra Leone , Guinea, the Gambia , Somalia and Egypt where more than half of the female population thinks the practice should continue. However, in most countries in Africa and the Middle East with representative data on attitudes 23 out of 30 , the majority of girls and women think it should end. Overall, the practice of FGM has been declining over the last three decades. In the 30 countries with nationally representative prevalence data, around 1 in 3 girls aged 15 to 19 today have undergone the practice versus 1 in 2 in the lates.
However, not all countries have made progress and the pace of decline has been uneven. Patil and A. In some countries, data have been collected through other nationally representative household surveys.
After a few years, the module was modified and has been included in DHS for 23 countries to date. This is derived from self-reports. In most surveys, eligible respondents are all girls and women aged 15 to The second indicator used to report on the practice measures the extent of cutting among daughters of girls and women of reproductive age 15 to If the eldest daughter was reportedly not cut, respondents were asked if they intended to have their daughter cut.
This was followed by questions about the procedure type, age at cutting and practitioner for the daughter most recently cut. As a result, prevalence estimates can be obtained for girls aged 0 to Therefore, the data on prevalence for girls under age 15 is actually an underestimation of the true extent of the practice. Since age at cutting varies among settings, the amount of underestimation also varies. That said, these data must be analysed in light of the extremely delicate and often sensitive nature of the topic.
First, women may be unwilling to disclose having undergone the procedure because of the sensitivity of the topic or the illegal status of the practice in their country.
However, even these data need to be interpreted with a degree of caution. Despite this, considerable challenges arise when examining trends, particularly when establishing a connection between programmatic activities and changes in prevalence levels over time.
First, prevalence can be compared from surveys in the same country from two or more points in time. Several important factors should be considered when examining trends in the practice:. Female genital mutilation FGM August
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