First-class maintained waterways, second-class maintained waterways, and third-class maintained waterways?: How to distinguish?
Inland waterway grades are classified according to the size of ships that can pass the river.
* First-class channel: navigable 3,000 tons
* Second-level channel: navigable 2,000 tons
* Third-level channel: navigable 1,000 tons, third-level channel The minimum standard for class-class waterway dimensions is a water depth of 3.2 meters and a bottom width of 45 meters. According to the "Inland River Navigation Standard" GB50139-2004, newly built bridges use one span to cross the river, and the bridge clearance height is not less than 7m. What type of maintenance is the main type of sudden failure maintenance
1. Regular maintenance
Regular maintenance is a type of preventive maintenance. It stipulates corresponding cycles based on the changing rules of the vehicle's technical condition and statistical analysis of faults, and performs maintenance on the vehicle according to the prescribed work content at certain intervals (or mileage).
Regular maintenance allows maintenance work to be carried out with preparation, facilitates organization and arrangement, and ensures maintenance quality. However, a car is a complex system. Since the working conditions of each component are different and the initial technical status is also inconsistent, their life spans are also different. If they are maintained according to the prescribed period, the life potential of some components will inevitably not be fully achieved. play. In addition, since the maintenance work is mandatory according to the plan, the manpower and material resources invested are often unnecessary for some components. Moreover, blind disassembly not only increases the maintenance workload, but also destroys the coordination efficiency of the components, causing the The inherent reliability of the component decreases. As for the resistance to sudden failures, regular maintenance is also ineffective.
2. On-demand maintenance
On-demand maintenance is also a type of preventive maintenance. It is based on failure mechanism analysis, regularly or continuously inspects or monitors the technical condition of the vehicle through diagnostic or monitoring devices, and organizes maintenance work based on the inspection results.
For on-demand maintenance, it is necessary to grasp the changing rules of the vehicle's technical condition, the allowable limits of technical condition parameters, fault characteristics, characteristics and their impact on the vehicle's working ability.
Because on-demand maintenance is performed when signs of failure are detected, it increases the effectiveness of the vehicle and maximizes the life potential of the vehicle components. Therefore, this is an ideal maintenance method.
3. Post-event maintenance
Post-event maintenance can give full play to the life potential of each auto part and avoid human errors caused by blind disassembly. Since many failures occur randomly, the use of post-event maintenance methods makes it impossible to make planned arrangements for repair work, making organization and management difficult. At the same time, when post-event maintenance is adopted, the failure rate is high because the timing of failure is not grasped in advance and it cannot be controlled. Moreover, when the failure occurs during transportation, it will affect the completion of the task. What department publishes waterway maintenance standards and inland waterway maps
According to inland waterway navigation standards, inland waterways are divided into seven levels. Level 1 waterways are navigable for ships above 3000T. According to the current national waterway implementation With the development of the industry, ships are developing towards larger sizes. With the improvement of waterway conditions, waterways for ships of 3000T and above have become very common. Just like the Yangtze River, ships of 5000T and above can now be passed all year round below Chongqing.
The water depth of the Yangtze River waterway maintenance in the 41st week of 2014
Forecast of the waterway maintenance standards of the Yangtze River trunk line in the 41st week (October 6th to October 12th, 2014)
Sequence
No.
River section
Planned maintenance water depth in October 2014 (m)
October 6, 2014 Maintenance scale forecast from Sunday to October 12 (water depth × width)
Main shallow water channels in the river section
Maintenance scale forecast
Remarks
< p> Waterway nameChannel
Water depth (m)
Channel
Width
(m)< /p>
Measurement time water level (m)
Water level station (navigation water gauge) name
Detection time
1
Hejiangmen~Wangye Temple
3.5
4.5×100
Yangliu Qi Waterway
4.5
100
6.30
Black-faced Guanyin
September 30, 10:00
Xianglutan Waterway
4.5< /p>
100
7.20
Golden Rooster Tail
September 30, 10:00
Jingkou Channel
4.5
100
6.80
Guanyin Hall
September 30, 10:00
2
Wangye Temple~Lanjiatuo
3.5
4.0×80
Shayuqi Waterway
4.0
80
6.00
Xiao Taozhu
September 30, 09:00
3
Lanjiatuo ~ Louxigou
3.5
3.7×100
Kuzhuqi Waterway
3.7
100
7.00
Huangji
September 30, 09:00
Zhanqizi Waterway
< p> 3.7100
7.50
Ertan
September 30, 09:00
Hu Family Beach Channel
3.7
130
10.08
Qingyanzi
September 30, 09:00< /p>
4
Louxigou～Yangjiaotan
3.5
3.7×100
Triangular Moraine Waterway
p>
3.7
100
11.20
Longfeng River
September 30, 09:00
Zhuerqi Waterway
3.7
100
13.62
Yangjiaotan
September 30, 09 Time
5
Yangjiaotan ~ Shantuo Bridge
4.0
4.2×150
Chaotianmen Waterway
4.2
150
13.62
Yangjiaotan
September 30, 08:00
6
Shantuo Bridge ~ Lidu Bridge
4.0
5.0×300
Changshou Waterway
5.0
300
171.00
Giethoorn Castle
September 30, 09:00
7
p>Lidu Bridge ~ Three Gorges Dam
4.5
4.5×150
Lidu Bridge ~ Miaohe River Section, Zhongshuimen ~ Xia Linjiang The actual maintenance water depth in the Ping River section is 4.5m. The actual maintenance standards of the waterway between Miaohe and Zhongshuimen are subject to the waterway information released by the Yangtze Three Gorges Waterway Bureau.