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1. What is the bending radius of the cable?
Cables must be actively or passively subjected to bending during the manufacturing, transportation, and installation and construction processes. When the cable is bent, the degree of bending is directly related to the bending radius of the cable.
1. The bending radius of the cable: Normally, we regard the bent cable as an arc, and the radius of the circle where the arc is located is the bending radius of the cable in the bending state.
2. The minimum bending radius of the cable: Due to the cable material and structural characteristics, the cable has a certain limit to withstand bending. The cable bending radius under this limit is the minimum bending radius of the cable.
2. The influence of too small cable bending radius on the cable
1. The effect of bending on the conductor
The cable conductor is made up of multiple single-core wires twisted at a certain pitch. The number of single wires and the pitch of the conductor determine the stability of the conductor during bending. Excessive bending will cause the conductor to become loose and loose. The protrusion directly affects the performance of the semi-conductive layer and insulating layer of the outer conductor.
2. The influence of cable bending on insulation
When the cable is bent with a certain bending radius, the insulation at the bend will undergo tensile deformation. When the bending exceeds the allowable minimum bending radius, it may cause insulation damage.
3. The effect of bending on metal shielding
Usually medium voltage cables are shielded by copper tape. When the cable is bent too much, the metal tape will wrinkle or curl, which will easily lead to insulation damage.www.rfcable.com.cn/en
Precautions for installation of flame-retardant and fire-resistant cables
The characteristics of flame-retardant and fire-resistant cables: have the function of self-extinguishing, and can maintain the normal operation of the electrical circuit for a period of time under burning conditions. Therefore, the installation of flame-retardant and fire-resistant cables can effectively control major disasters caused by cable fire and prolonged combustion, thereby improving the fire protection level of electric lines. So, what matters should be paid attention to when installing flame-retardant and fire-resistant cables?
1. When laying cables in the same pipeline, it is not advisable to configure both flame-retardant and fire-resistant cables and ordinary non-fire-resistant cables.
2. When the number of cables to be installed is small, fire-resistant paint, tape, etc. can be added to the cables.
3. Places with high safety performance requirements, such as oil tank farms, important wooden structure public buildings, dense wire tunnels, hospitals, shopping malls, etc., need to be equipped with Class A flame-retardant and fire-resistant cables.
4. In industrial buildings, important circuits such as fire protection, alarm, emergency lighting, breaker operation DC power supply, and emergency shutdown power supply for generating sets and other important circuits need to be equipped with Class A flame-retardant and fire-resistant cables.
5. When too many cables are laid in the same pipeline, the cables need to be laid in the fire-resistant trough box.
6. In order to reduce the failure rate of wire connectors in fire accidents, the number of connectors should be reduced as much as possible during installation to ensure that the lines can work normally in a fire. If branch wiring is needed, fire-proof the joints should be done.http://www.rfcable.com.cn/en
Special cables are cables that have special uses and can be used on specific occasions. Special cables are a series of products with unique properties and special structures. Compared with ordinary wires and cables with a large quantity and a wide range, special cables have the characteristics of higher technical content, stricter use conditions, smaller batches, and higher added value. Special cables often adopt new structures, new materials, new design calculation methods and new production processes.
Second, the characteristics and classification of special cables
Special cables have special functions due to their special use occasions or specific use conditions, such as high temperature or severe cold resistance, strong acid and alkali resistance, termite resistance, low noise, superconducting, waterproof, soft and wear-resistant, and environmental protection. . So far, special cables are mainly divided into four categories: high temperature resistant wire and cable, special structure and specific purpose wire and cable, functionalized wire and cable, and new green and environmentally friendly wire and cable.
Third, the diversified development direction of special cables
The development direction of special cables is diversified. The military industry has a large demand for light-weight and high-temperature-resistant cables. In terms of construction, fire-resistant and high-temperature resistant wires and cables and low-smoke, halogen-free and environmentally friendly wires and cables can effectively prevent fire and safety accidents. In fields such as medicine and national defense that require small signal measurement, low-inductance and low-noise wires and cables are needed. For oil platforms, deep well survey cables, heating and temperature control cables, and submarine integrated cables are needed. In urban power distribution, substations, power plants and other occasions that need to transmit large currents over short distances, superconducting cables are required. In terms of industrial intelligence, super-flexible, wear-resistant and easy to move drag chain cables are needed. In the application of locomotives and AC motors, frequency conversion cables are required.www.rfcable.com.cn/en
Five principles of circuit wiring in home decoration
Circuit wiring is an important part of home decoration. The quality of home decoration circuit wiring directly affects our future life, and will also affect our future circuit maintenance and transformation. Do you know how home decoration circuit wiring should be implemented and what wiring principles should be followed?
1. Principles of circuit design: walk on the top without walking on the ground, on the top without walking on the wall, and on the wall without walking on the ground.
2. The principle of circuit grouping: according to the circuit application in the home, carry out strong and weak current grouping, keep the distance between strong and weak current groups at 30-50 cm; group the circuits into living room, kitchen, bedroom and other applications according to the spatial layout of the family;
3. Circuit positioning principle: According to the placement of household electrical appliances, the layout of switches, the positioning of sockets, etc., carry out the planning and layout of the circuit.
4. Circuit grooving principle: The principle of horizontal and vertical grooving should be followed, and horizontal grooves should be opened as little as possible; if there are no more than 3 inflection points on the line, the shortest line should be planned and then grooved .
5. The principle of circuit buried pipe: circuit wiring generally adopts the method of concealed buried pipe. There are two types of wire pipes: cold-bent pipe and PVC pipe. Cold-bend pipes can be bent but difficult to break. It is recommended as the preferred choice for buried pipes.
Adhering to the five principles of circuit wiring in home decoration can enhance the safety of life electricity and provide convenience for future circuit maintenance and transformation.http://www.rfcable.com.cn/en
2. Overload operation: Due to long-term overload operation, the operating temperature of the cable far exceeds the maximum allowable temperature during normal heating, which makes the insulation material of the cable aging and dry, so it is easy to break down and cause the wire to catch fire.
3. Excessive contact resistance: The contact resistance is too large due to poor contact at the junction of line and line, line and switch, and line and other electrical equipment. When strong current passes, it will also cause local heating and high temperature and cause line fire.
4. Leakage: The quality problems of the wire, such as poor insulation performance or friction or scratches in the laying of the wire, will cause the wire to leak. The electric spark and high temperature caused by the leakage will cause the wire to catch fire.
Prevention of wire fire:
1. Short-circuit prevention: Use safe fuse electrical switches and select flame-retardant cables with high safety factors. When a short-circuit fault occurs on the electrical circuit, the fuse will blow and cut off the current, and the flame-retardant cable has its own self-extinguishing performance, which greatly reduces the spread of fire.
2. Overload prevention: Do not pull wires randomly. When using high-power electrical appliances, consider the acceptable range of wires and cables. for
To prevent aging and breakdown of insulating materials during overload operation, it is recommended to use wires and cables with better aging resistance and lower eccentricity.
3. Prevention of excessive contact resistance: The electrical wiring must be installed in strict accordance with the electrical installation regulations. If necessary, please ask a professional electrician.
Set up the line.
4. Leakage prevention: choose wires and cables with good insulation material quality and strong bending resistance. In addition, regular
Check electrical wiring and equipment, etc.www.rfcable.com.cn/en
Talking about the naming principle of wires and cables
The naming of wire and cable is usually related to its application occasion, category, material, and purpose. In order to facilitate memory, the naming of most wire and cable products usually needs to follow the following three principles:
1. Content principle: The product name should contain the following content.
(1) Product application occasion or classification name; (such as power cables, control cables, marine cables, wind engine cables, etc.)
(2) Product structure material or type (types include steel tape armor, steel wire armor, double aluminum tape, etc.);
(3) Important features or additional features of the product. Sometimes in order to emphasize a certain feature of the product, it can be written before the product name or before the corresponding structural description. Such as: flame-retardant, fire-resistant, termite-proof, corporate standards, etc.
2. Order principle: The description of product structure materials should be named in the order of conductor --> insulation --> inner sheath --> outer sheath --> armor type.
3. Abbreviation principle: for example, aluminum conductors are not allowed in automobile wires and flexible wires, so the conductor materials are not described.
Examples of product names are as follows:
1. The name of the cable: rated voltage 8.7/15kV flame-retardant copper core XLPE insulated steel tape armored PVC sheathed power cable, in which the content of the name is interpreted as:
"Rated voltage 8.7/15kV"-use occasion/voltage level
"Flame retardant"-emphasized features
"Copper Core"-Conductor Material
"Cross-linked polyethylene insulation"-insulating material
"Steel tape armor"-armor layer material and type
"Polyvinyl chloride sheath"-inner and outer sheath materials (the inner and outer sheath materials are the same, the inner sheath material is omitted)
"Power cable"-the name of the product category
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Isolation sleeve: The focus is on the word isolation. The isolation is between two different metals, such as the three-core YJV22 structure. There is a layer of PVC between the copper strip and the steel strip. At this time, the PVC plays the role of isolation. From chemical and physical From the perspective of consideration, the activities of copper and iron are different, and when they are in contact with each other, they will accelerate the oxidation of copper. Therefore, the isolation sleeve must be squeezed and cannot be wrapped, because there are gaps in the wrapping, which may cause mutual contact.
Lining layer: copper wire shielding, copper tape armoring, single-core power cable-this structure also has PVC between the shielding layer and the armoring layer, but since the two metals are of the same kind, they will not accelerate oxidation, so PVC does not need to be used. To the isolation effect, so in this case it is not called an isolation sleeve, but an inner liner. In addition, the inner liner may be wrapped.
Cushion: Generally, the word "wrap tape" is added in front of the cushion. This is used in many standards to describe its function. When the cable is armored, it is used together with the inner lining to strengthen the inner lining. The role of.
The inner lining can be squeezed or wrapped, while the isolation sleeve can only be squeezed. For cables with specifications above 10mm2, wrapping can save material costs. When the metal layer under the armor is different from the armor material, a layer of isolation sleeve must be squeezed to separate it. At this time, the isolation sleeve can replace the inner lining. Since the cores of medium voltage power cables are shielded by copper tape, and the cores of low voltage cables are unshielded, this is why we usually see why medium voltage armored cables have to squeeze the inner lining (isolation sleeve), while low voltage armored cables The reason to wrap the inner liner.www.rfcable.com.cn/en
Automatic Syringe with Feeding Tube
Constructed of durable plastics to be lightweight and economical. Comes with 32" soft non-kink, medical-grade, silicone tubing and stainless-steel reusable suction needles. Barrel is removeable and autoclavable for easy cleaning. Ergonomic handle design helps reduce hand fatigue. Precise dosage adjustments - 1 ml model adjusts from 0.25 ml to 1 ml; 2 ml model adjusts from 0.25 ml to 2 ml; 5-6 ml model adjusts from 0.25 to 6 ml. Comes with 3 adaptors (20 ml, 30 ml and 33 ml), 100 ml bottle protector and spare parts (3 o-rings and 1 spring).Get more news about Advanced Syringe Auto Feeder,you can vist our website!
Three parts syringe: syringe barrel, syringe plunger and syringe gasket.
Assemble Syringes Types: luer lock, luer slip, central-nozzle and ex-central nozzle syringes with needle or without needle.
Machine Features:
--Controlled by touch screen: Automatically eliminate unqualified products and raw materials control.
--Stainless steel material, not easy to get rusty. Won't bring any pollution to syringe and cleaning workshop.
Advantages
1. Equipped with spray-oil device
2. High efficient production
3. Auto stop when lack of material, and auto start when supply material.
4. Easy operate control system
The best wireless chargers for iPhone and Android in 2021
Embrace the future of charging with the best wireless chargers. Forget about plugging in cables to your smartphone or wirelessly chargeable accessories, just pop them on these stands and pads and watch them power up.Get more news about Wireless Charger,you can vist our website!
When it comes to picking the best wireless charger, it's not one size fits all. There are single-device wireless chargers that are great for supplying power to a phone and more versatile wireless chargers for those who want to juice up multiple gadgets at once, including a phone, Apple Watch and AirPods or AirPods Pro.
Based on our research, these are the best wireless chargers you can buy right now, whether you're looking for a cheap and simple Qi wireless charger or a device that can charge your phone and other gadgets at the same time. And with Apple's MagSafe now on the scene, there are more options popping up all of the time.
If you go for one of these chargers, and then decide your phone looks a little outdated in comparison, then we have the best Black Friday phone deals for you to peruse.The best wireless charger for most people is the Belkin Boost Up Wireless Charging Stand. It charges up to 10W and lets you rest your smartphone in both landscape and portrait orientations. This wireless charger is compatible with iPhone and Samsung devices.
The best wireless charger for Apple gear users is Apple's own MagSafe charger. It automatically attaches to the right point on the iPhone 12 or iPhone 13, and provides a zippy 15W of charging power.
If you want to charge more than one device at once, the best wireless charger for you is the the Logitech Powered 3-in-1 dock. It's on the pricey side at $129, but this accessory delivers juice to an iPhone, AirPods or AirPods Pro and Apple Watch all at the same time. There's also the Nomad Base Station Pro, which costs even more but looks much better and lets you charge from any point on the pad.Belkin's Boost Up Wireless Charging Stand is the best wireless charger available. It features up to 10W of power, charging iPhones up to 7.5W and Samsung up to 9W. All other Qi-enabled devices charge at 5W. Don't worry if your phone has a case; the Boost Up is compatible with cases that are up to 3mm thick.
The solid design lets you charge your phone in either portrait or landscape mode, so you can use your device while it's charging. The device features an LED indicator light for letting you know when it's charging, and a foreign-object-detection feature means it'll know when a phone isn't on it and shouldn't charge.
Take your pick of two colors: black and white. Belkin includes a wall adapter with a 4-foot power cord and offers a three-year warranty.
SALT-CAB Salt Mist Chamber in Poznań
The device can be used to evaluate samples in a salt chamber with varying temperature. This type of testing (also known by other names: salt spray tests, salt spray testing) is most commonly used to check the effectiveness of a production process. For practical reasons, all these terms are equivalent and mean the same thing.Get more news about Cab Test Chamber,you can vist our website!
Advantages:
Corrosion chamber allows comparative testing
All over the world, materials used by manufacturing industries are exposed to natural or industrial corrosion in the form of salt spray, humidity, smoke and vehicle exhaust. With the corrosion chamber, the corrosion resistance of materials such as paints and coatings can be predicted. The device meets national and international standards to ensure reliable and comparable results.
Salt chamber tests
The so-called distribution tower enables the mist to be distributed evenly in the test area.
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