Quality inspection index of wire and cable

The inspection of wire and cable has always been an important part of national standard wire and cable. The higher the quality inspection department of a wire and cable enterprise is, the better the quality of the wire and cable produced by the enterprise is and the more trustworthy it is. And the more stringent the third-party quality inspection department is, the more conducive to the development of the industry.

1.Measurement of dc resistance of wire

The conductor cores of electric wires and cables mainly transmit electric energy or electrical signals. Conductor resistance is the main index, its electric performance of the ac voltage effect when the wire core resistance due to the surface of skin effect and proximity effect than dc voltage function, but when the electric frequency of 50 hz and small lines of standard specifies requirements that are only now the core of dc resistance or the resistivity is more than standard value, through the inspection can be found in the process of production of certain defects, such as broken wire or part of the single fracture; Traverse section does not meet the standard; Incorrect length of product, etc.

2. Test insulation resistance

The insulation resistance is an important index to reflect the insulation characteristics of wire and cable products, which is closely related to the electrical resistance, dielectric loss, and the gradual deterioration of insulation materials in the working state. For communication cables, if the insulation resistance between wires is too low, it will also increase circuit attenuation, cross-talk between circuits and long-distance power supply leakage on the conducting wire core, etc., so the insulation resistance shall be higher than the specified value.

3. Measurement of capacitance and loss factor

When the cable is applied with an AC voltage, a current flows through it. When the amplitude and frequency of the voltage are constant, the capacitive current is proportional to the capacitance of the cable (Cx). For ultra high voltage cables, the current of the capacitance may be comparable to the rated current, which becomes an important factor limiting the cable capacity and transmission distance. Therefore, the capacitance of the cable is also one of the main electrical performance parameters. By measuring the capacitance and the loss factor, it can be found that the insulation is affected by moisture, the insulation layer and the shielding layer fall off and other kinds of insulation deterioration phenomenon. Therefore, the measurement of capacitance and TAN delta is always carried out in the cable manufacture or operation.

4. Insulation strength test

The insulation strength of wire and cable refers to the ability of the insulation structure and material to withstand the action of electric field without breaking down. In order to check the quality of wire and cable products and ensure the safe operation of the products, all types of insulation wires and cables generally need to conduct insulation strength tests. The insulation strength test can be divided into pressure test and breakdown test. The voltage of time is generally higher than the rated working voltage of the test product. The specific voltage value and withstand voltage time are stipulated in the product standard. Through the withstand voltage test, the reliability of the product operation under the working voltage can be tested and serious defects in insulation can be found, as well as some shortcomings of the production process can be found

5. Aging and stability test

The aging test is a stability test that can maintain stable performance under the action of stress (mechanical, electrical, thermal). Thermal aging test: The simple thermal aging test is to test the characteristics of the test product under the action of heat aging. The test product is placed in an environment with a certain value above the rated working temperature, so as to obtain a shorter life at a higher temperature.

6. Thermal stability test

The thermal stability test is to evaluate the insulation stability by measuring some sensitive performance parameters after the cable is heated by current and subjected to a certain voltage during a certain period of heating. Insulation stability test can be divided into long-term stability test or short-term accelerated aging test.

Us gas capacity and demand and cables

The US energy Information Administration (EIA) said in its Short Term Energy Outlook (STEO) that the days of the us have been reduced by government measures to slow the spread of the coronavirus, reducing economic activity and energy prices.

Gas production and demand will fall from last year’s record highs in 2020 and 2021.
The EIA expects dry gas production to fall from a record high of 92.21 BCFD (BCF/d, the same below) in 2019 to 89.24 BCFD and 84.23 BCFD in 2021.

The EIA also expects gas consumption to decline from a record 84.97 BCFD in 2019 to 82.35 BCFD in 2020 and 78.62 BCFD in 2021.

This would be the first annual decline in consumption since 2017 and the second consecutive decline since 2006.

The EIA’s July 2020 gas supply forecast is lower than its June forecast of 89.65 BCFD and its latest 2020 demand outlook is higher than its June forecast of 81.87 BCFD.

It forecast US LNG exports to reach 5.35 BCFD in 2020 and 7.28 BCFD in 2021, up from a record 4.98 BCFD in 2019 and below its June forecast of 2020

In 2021, it was 7.31 BCFD.

Carbon emissions from burning fossil fuels are expected to fall from 5.130 billion tonnes in 2019, the lowest level since 1992, to 4.507 billion tonnes in 2020, the lowest level since 1983, and then to follow

Increase in coal use to 4.775 billion tons by 2021.

Demand is down and the electricity market favours renewables

The COVID-19 pandemic shows the power market’s preference for renewables in the face of falling demand, and the clean energy transition is likely to accelerate, Moody’s reports.

“Coal generation has continued to decline, while renewable energy has shown greater resilience in key markets in the United States, Europe, China and India,” the report said.

As a result of the blockade, electricity demand in India has fallen by 20 per cent, which has had a significant impact on coal production.

Both business and household electricity demand are expected to be severely affected by the recession and weaker expectations for long-term growth. Conventional energy production, such as coal and oil, also declined, the agency said.

Worldwide, renewable energy accounts for most of the recent new capacity, which continues to displace coal-fired power. Moody’s said the trend was expected to continue as electricity demand fell sharply as a result of the blockade.

“Covid-19 could have a ratchet effect, limiting any rebound in coal production and accelerating declines in the US and Europe for several years,” the rating agency said.

Moody’s also predicts that increased use of biofuels, electric cars and improved engine efficiency will increase the likelihood that oil demand will flow over time. While most developed countries already have targets and incentives for rapid adoption of electric vehicles over the next decade, India has yet to enact such a policy.

Renewable energy growth hit a record high in 2019

On June 17, the 69th edition of THE BP Statistical Yearbook on World Energy was released. The Yearbook points to continued strong growth in renewable energy. Renewable energy, led by wind and solar, is growing at record levels, accounting for more than 40% of primary energy growth in 2019. Meanwhile, coal consumption has fallen for the fourth time in the past six years, and its share of the global energy mix has fallen to its lowest level in 16 years.

But the structural picture remains grim. Although coal’s share fell last year, it is still the biggest source of electricity, accounting for more than 36% of global output. Renewables, by contrast, account for only 10 per cent, and will need to grow even more strongly over the next three decades to decarbonise the sector.

More worrying is the trend in carbon emissions. Carbon emissions growth slowed to 0.5% in 2019, a lower rate that suggests some optimism. But this deceleration comes against the backdrop of a huge 2.1 per cent increase in carbon emissions in 2018. As the world emerges from the coVID-19 crisis, the energy transition will also require decisive changes towards a more sustainable path.

To achieve net zero emissions by 2050, the world would need to reduce carbon emissions by the same amount every other year for the next 25 years, or 2.6 billion tonnes, the yearbook says.

This can only be achieved through a fundamental shift in behaviour, namely through more efficient use of resources and energy, and the implementation of all the technologies that are available in zero and low carbon energy, including renewable energy, electrification, hydrogen, CCUS (carbon capture and storage), bioenergy, and more.

In terms of consumption, China has become the largest contributor to global energy consumption growth, accounting for more than three quarters of global net growth. In the net zero vision, China’s energy policy choices and paths will directly affect the future pattern of global energy consumption.

What will affect the cable life?

Popularity has very high power, manufacturing from all walks of life cannot leave the electricity, the power is inseparable from the cable, so the service life of the cable will directly affect the safety of production, the service life of the cable is determined by the oxidation induction period of sheath material, use 20 years general cable design, real life is far greater than this value.
What are the factors that lead to reduced cable insulation?
1. External damage
From the operation analysis in recent years, especially in the rapid economic development today, a considerable number of cable faults are caused by mechanical damage.
2. Damp insulation
This is also common, usually at the end of a cable in a buried or drain pipe. For example: cable joints made unqualified and in humid climate conditions to do the joint, will make the joint water or mixed with water vapor, for a long time under the action of the electric field to form water branches, gradually damage the cable insulation strength and cause failure.


3. Chemical corrosion
Cables buried directly in areas with acid and alkali effects will often cause corrosion of the cable armor, lead or outer sheath. Long-term chemical or electrolytic corrosion of the protective layer will lead to failure of the protective layer and reduced insulation, and also lead to cable faults. Change: the cable corrosion situation of unit is quite serious.
4. Long-term over-load operation
In overload operation, due to the thermal effect of current, the conductor will inevitably heat up when the load current passes through the cable. Meanwhile, the skin effect of charge, the eddy current loss of steel armor and the insulation medium loss will also generate additional heat, which will increase the cable temperature. In long-term overload operation, excessive temperature will accelerate the aging of insulation and even the insulation will be broken down. Especially in the hot summer, the temperature rise of the cable often leads to the first breakdown of the cable insulation weakness, so in the summer, the cable faults are particularly frequent.


5. Cable joint failure
The cable joint is the weakest link in the cable line. The fault of the cable joint caused by the personnel’s direct fault (poor construction) often occurs. In the process of making the cable connector, if the original network such as the joint is not pressed tightly and the heating is not sufficient, the insulation of the cable head will be reduced, thus causing an accident.
6. Environment and temperature
The external environment and heat source in which the cable is located will also cause the cable temperature to be too high, the insulation to break down, and even the explosion and fire.
7. Other factors
Normal aging of cable body or other reasons such as natural disasters.

What is aluminium alloy power cable?

Aluminum alloy power cable is a new material power cable with AA8030 series aluminum alloy material as the conductor, adopting advanced technology such as special roll forming wire twisted production process and annealing treatment. Alloy power cable made up for the inadequacy of previous pure aluminium cable, although there is no improve the conductive properties of the cable, but the bending performance, creep resistance and corrosion resistance are greatly improved, to ensure that the cable for a long time to keep continuous stable performance when overload and overheat, the AA – 8030 series of aluminum alloy conductor, which can greatly improve the conductivity of the aluminum alloy cable, high temperature resistance, and solves the problem such as pure aluminium conductor, creep. The conductivity of aluminum alloy is 61.8% of that of copper IACS, the most common reference material. But at the same volume, the actual weight of an aluminum alloy is about a third that of copper. Therefore, the weight of the aluminum cable is about half that of the copper cable with the same load flow. The use of aluminum cable instead of copper cable can reduce the weight of the cable, reduce installation costs, reduce equipment and cable wear, making installation easier.
Aluminum alloy cables add copper, iron, magnesium, silicon, zinc, boron and other alloying elements into the electrical aluminum. At the same time, through process adjustment, the mechanical properties of aluminum alloy conductors are greatly improved to avoid the problems of low elongation, poor creep resistance and poor flexibility of pure aluminum conductors and increase the connection reliability of the cable system. In addition, keep the electrical properties of aluminum alloy and electrical aluminum conductor equal, at 61%IACS above.
Alloy power cable made up for the inadequacy of previous pure aluminium cable, although there is no improve the conductive properties of the cable, but the bending performance, creep resistance and corrosion resistance are greatly improved, to ensure that the cable for a long time to keep continuous stable performance when overload and overheat, the AA – 8030 series of aluminum alloy conductor, can significantly improve the conductivity of the aluminum alloy cable, high temperature resistance, at the same time solve the pure aluminium conductor electrochemical corrosion, creep, etc.
The conductivity of aluminum alloy is 61.8% of that of copper IACS, the most common reference material. But at the same volume, the actual weight of an aluminum alloy is about a third that of copper. . Therefore, the weight of the aluminum cable is about half that of the copper cable with the same load flow. The use of aluminum cable instead of copper cable can reduce the weight of the cable, reduce installation costs, reduce equipment and cable wear, making installation easier.
Aluminum alloy power cable has good mechanical properties and electric properties, it can be widely used various fields of national economy, such as common people residence, high-rise buildings, elevators, both large supermarket shopping malls, subway, airport, railway stations, hospitals, Banks, office buildings, hotels, postal telecommunications building, exhibition hall, library, museum, ancient buildings, schools, electricity, building, public places of entertainment, tunnels, underground buildings, warehouses, etc., can also be used for metallurgy, steel, coke, coal mines, power plants, power transmission and transformation station, shipbuilding, petroleum, chemical, aerospace, military, medicine, nuclear power plants, paper and other industries, And home appliances, cars, public transportation, and so on.

CRU upgraded China’s optical fiber and cable market demand forecast

With the novel Coronavirus epidemic under rapid control in China and the policy requirement to speed up the construction of new infrastructure such as 5G and big data center, the three domestic operators have also substantially increased the capital expenditure related to 5G. All these have provided further room for the growth of demand for optical fiber and cable.

Economic recovery CRU raised China’s optical fiber and cable market demand forecast

Michael Finch, director of CRU cables, said that given the latest statistics, worldwide demand for cable is expected to contract by 12-13 per cent year-on-year in the first quarter, falling below 100 million core kilometres, the lowest level since the fourth quarter of 2015.

Looking at the Chinese market, Michael Finch points out that demand for fiber optic cable in China has collapsed in Q1, down 18.6% year on year. Meanwhile, In Q1 of 2020, China will account for only 44 percent of the global demand for optical cable, compared with 53 percent in the same period of 2018.

Michael Finch said, “While fTTX-related demand continues to weaken, increased capital spending and a greater focus on 5G will support growth in China’s fiber demand. So we think the market will be brighter for the rest of 2020.”

It is clear that the signs of China’s economic recovery are becoming more and more obvious, and all eyes are now on the bidding of China’s three major operators. Against this backdrop, CRU raised its forecast for the Chinese market in 2020, with a projected demand decline of 5.7%. Michael Finch noted that CRU had forecast a 9% decline in February.

According to Michael Finch, China’s naked fiber market will be dominated by destocking in 2020, and the country’s naked fiber production is expected to fall 14 percent for the full year, while fiber optic cable production will fall 5 percent. Meanwhile, Michael Finch notes that despite the difficulties, many Chinese manufacturers will seek opportunities to expand exports this year.

In asia-pacific, excluding China, overall demand will remain weak in 2020, especially in India. In addition, in The North American market, higher demand growth was supported by regional protection and increased capital spending by U.S. carriers such as Verizon. However, in the European market, due to the impact of Q1 and Q2 epidemic, the demand showed a significant decline. “The delay in 5G deployment across Europe and the Asia-Pacific region has also affected the demand for fiber optic cables in the region to some extent.” Michael Finch says.

According to Michael Finch, operators are experiencing certain performance and financial pressures as a result of the outbreak, which will affect their investment and deployment plans. According to the latest estimates, global demand for optical fiber and cable is expected to drop by 3.6% in 2020, compared with a 1.9% decline in the absence of the epidemic. However, CRU also raised its market forecast for 2021 to 10.5% from 9.3%.

This summer, U.S. electricity demand fell to its lowest level since 2009

Summer electricity demand in the US is expected to be the lowest since 2009, according to the US Energy Information Administration.
The summer demand level from June to August is expected to be 998 billion kilowatt-hours, down 5% from last summer’s demand, the report said. The lower power demand is mainly due to the coronavirus pandemic and its effects.
Compared with demand in 2019, the EIA said it expected residential electricity use to increase by 3 per cent, while commercial electricity use would fall by 12 per cent and industrial use by 9 per cent.
The EIA says coal production is likely to be lower than last summer. Coal is forecast to generate 178 billion kilowatt-hours of electricity, down from 272 billion kilowatt-hours last year.
It said it expected coal to account for just 17 per cent of electricity generation this summer, down from 24 per cent last summer.
Gas is expected to grow from 460 billion KWH last summer to 467 billion KWH this summer, with low gas prices making it attractive. Natural gas is expected to account for 44% of electricity generation this summer, up from 41% last year.
The EIA says the share of wind power will reach 7% this summer and utility-scale solar will grow to 3%.

China’s optical fiber and cable market is recovering

With the novel Coronavirus epidemic under rapid control in China and the policy requirement to speed up the construction of new infrastructure such as 5G and big data center, the three domestic operators have also substantially increased the capital expenditure related to 5G. All these have provided further room for the growth of demand for optical fiber and cable.

Economic recovery CRU raised China’s optical fiber and cable market demand forecast

Michael Finch, director of CRU cables, said that given the latest statistics, worldwide demand for cable is expected to contract by 12-13 per cent year-on-year in the first quarter, falling below 100 million core kilometres, the lowest level since the fourth quarter of 2015.

Looking at the Chinese market, Michael Finch points out that demand for fiber optic cable in China has collapsed in Q1, down 18.6% year on year. Meanwhile, In Q1 of 2020, China will account for only 44 percent of the global demand for optical cable, compared with 53 percent in the same period of 2018.

Michael Finch said, “While fTTX-related demand continues to weaken, increased capital spending and a greater focus on 5G will support growth in China’s fiber demand. So we think the market will be brighter for the rest of 2020.”

It is clear that the signs of China’s economic recovery are becoming more and more obvious, and all eyes are now on the bidding of China’s three major operators. Against this backdrop, CRU raised its forecast for the Chinese market in 2020, with a projected demand decline of 5.7%. Michael Finch noted that CRU had forecast a 9% decline in February.

According to Michael Finch, China’s naked fiber market will be dominated by destocking in 2020, and the country’s naked fiber production is expected to fall 14 percent for the full year, while fiber optic cable production will fall 5 percent. Meanwhile, Michael Finch notes that despite the difficulties, many Chinese manufacturers will seek opportunities to expand exports this year.

In asia-pacific, excluding China, overall demand will remain weak in 2020, especially in India. In addition, in The North American market, higher demand growth was supported by regional protection and increased capital spending by U.S. carriers such as Verizon. However, in the European market, due to the impact of Q1 and Q2 epidemic, the demand showed a significant decline. “The delay in 5G deployment across Europe and the Asia-Pacific region has also affected the demand for fiber optic cables in the region to some extent.” Michael Finch says.

According to Michael Finch, operators are experiencing certain performance and financial pressures as a result of the outbreak, which will affect their investment and deployment plans. According to the latest estimates, global demand for optical fiber and cable is expected to drop by 3.6% in 2020, compared with a 1.9% decline in the absence of the epidemic. However, CRU also raised its market forecast for 2021 to 10.5% from 9.3%.

Cable raw material copper, trend analysis in July

Analysis of the main products of cable raw materials (copper): According to the monitoring data of the cable network, the domestic spot copper price continued to fall sharply in July, and the overall copper price fell during the month. The average spot copper price in the beginning of the month was 42585. RMB/ton, the average spot copper price at the end of the month was 39,030 yuan/ton, and the price dropped by 3555 yuan/ton, a decrease of about 8.35%.

Macroscopically, abroad, the minutes of the Federal Reserve’s June meeting announced recently confirmed the recovery of the US economy. The Federal Reserve’s interest rate hike in September may intensify. This topic may still be the focus of the market in August. However, the US GDP in the second quarter fell short of expectations. It was not easy to realize the interest rate hike in September. What is more certain is that the strength of the US dollar will not change, which may trigger a new round of upsurge of funds leaving the commodity market, which will also put pressure on copper prices. On the domestic front, the current Chinese economy is still operating at a low level. Although the Chinese government continues to introduce loose monetary policy in the second half of the year, it has limited room for short-term boost to the real economy. Therefore, the copper market may still be under pressure in the first half of August. When the off-peak season alternates, copper prices may rebound.

Market: Since the second quarter, the downstream operating rate has gradually increased, and through the arrival of the peak season of copper pipes and other industries, the overall market turnover has improved, but year by year, this year’s peak season is not busy. Affected by the weakening of consumption in the off-season in July and the weakness of China’s economy, spot copper prices have dropped sharply, but merchants’ adjustments have remained stable and no selling has been seen. After the copper price hit a new low, suppliers are reluctant to sell. When copper supply has shrunk, consumption has shrunk, and the overall economy is severely severe, copper prices are unable to rebound, and the subsequent continued decline may break through.

Inventory: LME and Shanghai copper inventories continued to show a slight growth trend this month. The latest statistical data shows that LME copper stocks reported 345,475 tons, which is a bit higher than before; while in the past week, Shanghai copper stocks on the Shanghai Futures Exchange increased slightly to 103,117 tons. Inventory has been in a downward channel for several months, but it increased slightly in July. The growth in July may be related to the recent cross-market arbitrage. Due to the continued profitability of imports, the positive arbitrage of buying LME copper and selling Shanghai copper has the opportunity. This may attract some traders to ship the goods to the warehouse, but the overall amount of change is not large. . At present, the overall supply pressure of copper is not great, and the difficulty of copper price upwards still comes from the shrinkage of the demand side.cable cu

Outlook forecast: July economic indicators have been significantly eased compared to the previous month, but the market focus has remained on the economic side. The recent US data has been weak and unfavorable, but the dollar is still strong, putting pressure on basic metals such as copper, plus China Copper consumption has always been in a weak position, which has greatly reduced global copper consumption. Therefore, copper prices have been unable to rebound and have fallen frequently. In the short term, there is still room for rebound in copper prices, but in the long run, US interest rate hikes have reached the long-term strength of the US dollar index, coupled with the copper market demand has not yet recovered significantly, copper prices will weaken again later.

One of the largest submarine optical cable projects in the world

China Mobile International Corp, Facebook, MTN GlobalConnect, Orange, STC, Egypt Telecom, Vodafone and WIOCC have announced a partnership to build 2Africa, the most comprehensive undersea fiber optic cable serving the African continent and the Middle East, and will also connect through East Africa and other undersea cables to expand connectivity with Asia.Wires and cables

The developer has awarded Alcatel Subsea Network the contract to build the cable to greatly enhance connectivity throughout Africa and the Middle East.

2Africa is 37,000 km long and will connect Europe (east via Egypt), the Middle East (via Saudi Arabia) and 21 landing sites in 16 African countries, according to the report. 2Africa will provide much-needed Internet capacity and reliability across much of Africa, complement the rapidly growing capacity demand in the Middle East, and support further growth in 5G and fixed broadband access.

In countries where the 2Africa cable will land, service providers will have access to operator neutral data center or open access cable landing station capacity on a fair and impartial basis. This will support the development of a healthy Internet ecosystem by greatly enhancing the accessibility of businesses and consumers.Wires and cables

2Africa Cable will implement a new technology, ASN SDM1, which will enable the deployment of up to 16 pairs of optical fibres instead of the eight pairs supported by earlier technologies, resulting in greater and more cost-effective capacity. The cable will adopt optical switching technology to achieve flexible bandwidth management. The cable burial depth is also 50% higher than in older systems, and cabling will avoid known locations of seabed interference, all of which helps ensure the highest level of availability.

The system is scheduled to enter service in April 2023 and will deliver more than the total capacity of all submarine cables serving Africa today, with key components designed to have a capacity of up to 180Tbps. Once completed, it will be one of the largest undersea cable projects in the world.Wires and cables