【Special Article】After the Rekindling of the Turmoil, a Brief Discussion on Gas Meters (Residential Users)

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According to media reports, Chongqing Gas replaced expired gas meters for users, causing an uproar due to gas fee disputes, and Chongqing Gas was on the cusp of public opinion. Gas users and the public suspect that the gas meter is inaccurate and that the gas meter is overcharged. Although the government finally announced that the gas meter has been inspected to meet the requirements of the national standard, it still has not dispelled the doubts of gas users and the public about the accuracy of gas meter measurement, and media public opinion is still fermenting.

The membrane gas meter (residential user) is a legal measuring instrument for trade settlement between urban gas enterprises and gas users stipulated by the state. A membrane gas meter is a volumetric flow meter that uses a flexible, thin-walled measuring chamber to measure the volume of gas. The state has clear legal provisions on measuring instruments. Do not use substandard measuring instruments, or destroy the accuracy of measuring instruments. It is not allowed to manufacture or sell unqualified measuring instruments. Therefore, the gas meter must be strictly inspected and meet the requirements of the national standard before leaving the factory. Residential users use membrane gas meters, and the accuracy level of the gas meter is 1.5, and the allowable error is ±1.5%.

The working principle of the membrane gas meter: the gas meter is a volumetric gas flow meter, which uses a flexible diaphragm metering chamber to measure the gas volume flow. Under the effect of pressure difference, the gas enters the metering room alternately through the distribution valve, fills the rear exhaust outlet, and at the same time promotes the flexible diaphragm in the metering room to reciprocate the movement, and converts the circulation process of inflation and exhaust into the corresponding gas volume flow through the conversion mechanism, and then transmits it to the counter through the transmission mechanism to complete the gas accumulation metering function. To put it simply, the power of the membrane gas meter is to rely on the power of the gas to drive the reciprocating motion of the flexible diaphragm in the meter, and transmit it to the counter through the transmission mechanism to complete the metering function. Similarly, gas users feel that the newly replaced gas is faster than the original gas meter, which is also related to the working principle of the membrane gas meter. The flexible diaphragm of the gas meter begins to age after a certain period of use, and the action becomes slower, and the gas meter becomes slower, so this also makes the user feel that the newly replaced gas meter is fast.

In other words, it is impossible for the gas meter to move around to generate a meter without using gas. Only in the case of gas leakage from gas facilities and gas appliances behind the gas meter, the end number of the gas meter will walk around to generate a meter. At the same time, with the improvement of living conditions, some residents use thermostatic water heaters, which will also lead to an increase in gas costs. Thermostatic water heater is the user to control the temperature of the water at a certain temperature, the water heater to ensure a constant temperature, it is necessary to keep burning to ensure that the temperature of the water does not decrease, and there is set hot water for people to use at any time.

The development of membrane gas meters has gone through two processes. The first is the initial gas meter (hand reading) stage, the second is the IC card membrane gas meter (hereinafter referred to as the IC card meter) stage, and the third is with the development of science and technology, the IC card meter is also developing, from the ordinary IC card meter (sound and light alarm) to the liquid crystal display IC card meter stage, and then to the radio frequency meter (non-contact meter), until the wireless remote meter, ultrasonic meter and now vigorously promoted Internet of Things meter. The Internet of Things meter greatly facilitates gas users, and users can directly purchase gas on their mobile phones without going to the business hall of the city gas enterprise to buy gas.

With the rapid development of the gas industry and the increase of the urban gasification rate, natural gas has entered thousands of households to bring great convenience to the lives of urban residents, and the people no longer have to carry gas canisters up and down the stairs. Subsequently, there are also disputes with users over gas charges due to metering problems.

In the early days, urban gas enterprises installed ordinary meters (hand-read meters) for users. General meter (manual meter reading) ordinary membrane gas meter, using manual household meter reading charging method. It is difficult to enter the household, the cost is high, the gas fee is difficult to recover, and the operation and management expenses of urban gas enterprises are large. IC card meters have the function of prepayment, which solves the problem of charging and greatly saves labor costs. Urban gas enterprises do not need to go to the user's home to read the meter, disturbing the user, which is also very convenient for the user. However, various problems are also encountered in the use of IC card gas meters, because IC card meters can not be supervised for a long time when installed in the user's home, and the safety inspection of urban gas enterprises is once every two years. Whether the gas meter is normal or not, whether there is a fault, the city gas enterprise is not clear. The failure of the gas meter can only rely on the user to report for repair, resulting in some users owing a huge amount of gas bills, which cannot be recovered by the urban gas enterprise, affecting the company's operating income, and then leading to gas fee disputes with users. There is no essential difference between the general meter (hand meter) and the IC card meter, both of which are national legal measuring instruments. It's just that the charging method is different, which is a question of whether the user pays first or later, or whether the user uses gas first or later.

IC card membrane gas meter is a gas metering device with pre-purchased gas volume function composed of membrane gas meter as the metering base meter, IC card as the medium, and a controller installed. From this, it can be seen that the IC card gas meter is divided into two parts: the IC card prepaid part (control part) and the base meter part (metering part). The IC card (control part) is an add-on device that can be added to the base table to realize the corresponding function. It is allowed to install additional devices that perform certain functions, such as prepaid devices, pulse generators, and secondary devices for industrial and commercial meters, on the base meter, but the metering performance of the gas meter cannot be affected. Essentially, the prepaid part of the IC card (the control part) is just an add-on to the gas meter and does not participate in the metering.

The relevant national regulations also stipulate that the base meter has a basic measurement function, which directly displays the original data of gas consumption and is a measuring instrument that is separated from other additional functions. The gas consumption of gas users is subject to the data displayed in the base table. The key to the IC card gas meter is the control part (solenoid valve). If the control part is faulty, that is, the solenoid valve cannot be completely closed or is in a half-open state, all functions will fail, resulting in the user can not use gas normally. The solenoid valve cannot be closed normally, because of temperament, and there are also reasons for user use. The user does not replace the battery on time. At the same time, it is not excluded that the user man-made damage to the control part of the IC card will cause the control part of the IC card to fail, and then the user will exceed the gas consumption, resulting in gas fee disputes.

There is a user card socket on the IC card meter, and the water vapor generated by the user when cooking causes the kitchen to be damp and the harsh environment caused by cooking fumes, which corrodes the main board of the IC card gas meter and causes the IC card meter function to fail.

The IC card and gas meter are out of service, and the electronic components are aging and damaged, resulting in the failure of the control function of the IC card meter. At the same time, the overdue service of gas meters will also cause certain legal risks to urban gas enterprises. According to the relevant regulations of the state, the gas meter with a maximum flow rate of Qmax≤10m3/h and used for trade settlement will only be subject to the first mandatory verification, which will be used within a time limit and replaced at the expiration date. The service life of gas meters with natural gas as the medium is generally not more than 10 years. The service life of gas meters with artificial gas, liquefied petroleum gas, etc. as the medium is generally not more than 6 years.

The IC card gas meter cannot be measured due to the failure of the base meter (mechanical counting part), which leads to gas bill disputes between urban gas enterprises and users.

In short, gas meters are legal measuring instruments for trade settlement between urban gas enterprises and users. The IC card table is composed of two parts: the prepaid control part and the base table. When there is a discrepancy between the base meter measurement data and the data record recorded in the control part of the IC card, the base meter measurement data shall be used as the basis for settlement.

Residential user service has a certain particularity, basically the user's gas facilities and gas equipment have faults and problems, and the urban gas enterprise will send people to provide door-to-door service after the user reports for repair, so it is a passive service. In accordance with the provisions of the city gas regulations, the gas of urban gas enterprises shall provide users with free security inspections on a regular basis. Most provincial and municipal gas management regulations stipulate that free security checks are provided to residential users once every two years or a year. Therefore, the security inspection work is that the city gas enterprise takes the initiative to serve users and find problems. Checking whether the gas meter is working properly is also an important part of the safety inspection.

Therefore, whether it is passive service or active service, we should not give up the opportunity to publicize every door-to-door to users, not only to publicize the safe use of gas, but also to publicize the basic knowledge of gas meters (IC card meters) of gas facilities. Maintenance personnel and security personnel come to the door to find that the IC card meter is faulty, and the user's gas purchase does not match the amount of excess gas, inform the user and ask the user to sign for approval. Because the law stipulates that users have the right to know, the staff of urban gas enterprises have the obligation to inform users to avoid the risk of legal disputes.

If gas users have doubts about the accuracy of gas metering, they can identify the gas meter through a third-party qualified appraisal agency, or they can be arbitrated by a metering arbitration institution or resolved through legal means.

Metrological disputes refer to disputes arising from the accuracy of measuring instruments. The handling of measurement disputes shall be subject to the data of the verification and testing of the national measurement benchmark or social public measurement standards. Arbitration verification refers to the measurement verification and testing activities for the purpose of adjudication carried out by using measurement benchmarks or social public measurement standards. Measurement mediation refers to mediation between the parties to the measurement dispute under the auspices of the measurement administrative department of the people's government at or above the county level. If one or both parties are not satisfied with the first arbitration verification, they may apply to the metrology administrative department of the people's government at the next higher level for the second arbitration verification within 15 days from the date of receipt of the notice of the arbitration verification result. The arbitration verification conducted by the metrology administrative department of the people's government at the next higher level shall be the final arbitration verification.

Shanghai first issued the Measures for the Settlement of Civil "Three Meters" Metering Disputes, "Specifications for the Measurement and Disposal of Civil Water Meters, Electric Energy Meters, and Gas Meters" (hereinafter referred to as the Disposal Specifications), which became the first standard for civil "Three Meters" measurement disputes in the country and guided the handling of disputes. The "Disposal Specification" stipulates the refund of expenses and the time limit for verification that resident users are concerned about.

It can be seen from the turmoil of heavy gas charges that gas users suspect that there are problems of price adjustment, ladder gas fees, and meter reading and estimation of gas fees, which are caused by the superposition of various factors. In essence, it has nothing to do with the accuracy of gas measuring instruments, some people use network media to infinitely amplify the inaccuracy of gas measuring instruments and overcharge, but most of the gas users and the public do not know much about the working principle of gas measuring instruments, which is also related to the lack of publicity of gas measuring instruments by urban gas enterprises.

Resources:

1《膜式燃气表检定规程JJG 577—2012》

2《燃气服务导则GB/T28885-2012》

3《IC卡膜式燃气表》CJ/T112-2008

4《膜式燃气表》GB/T6968-2019

5. Measures for Arbitration Verification and Metrology Mediation (promulgated by the State Bureau of Metrology on October 12, 1987)

6. Metrology Law of the People's Republic of China