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What is Extrusion
If you’re searching for a copper extrusion manufacturer or a copper extrusion supplier, you might be curious about what extrusion involves. At its core, metal extrusion is a process that’s specifically designed to create objects of a cross-sectional profile. During the process, some material is sent into a die of the choice cross-section.
One of the main reasons why people utilize metal extrusion is because it creates very complex cross-sections. For example, if you’re looking for custom copper extrusions, you may want more complex cross-sections. Moreover, if you’re working with brittle materials, you don’t need to worry. Any material used will only encounter sheer and compressive stress, helping it to endure the process.
Multiple or Whole
Not every extrusion process is the same. If you need something longer, consider going with a continuous extrusion process. If you need multiple pieces, consider going with a semi-continuous extrusion process. The real difference between these two processes is that they either create one large piece or multiple smaller pieces. Either process can occur while the material is hot or cold.
Step by Step
First, for either hot or warm extrusion, the material is heated. The material is then set in a container on a press. Afterward, a dummy block is set behind the material. A ram pushes out the material, sending it out of the die. If better properties, the material might be heat treated or cold worked to produce the final result.
This process happens at a temperature above the point at which the material can recrystallize. Because of this, hot extraction is a kind of hot working process. Throughout the process, the material is kept from hardening. This allows materials to pass through the die easier. Generally, hot extrusions involve using a horizontal hydraulic press then cold drawn to final dimensions.
This kind of extrusion is normally done at either room temperature or near room temperature. However, unlike hot extrusions, cold extrusions do not require oxidation and can provide better material strength. Cold extrusions can also be completed at high speeds, allowing them to produce more finalized products in shorter amounts of time.
When you talk to copper extrusion manufacturer, consider asking them what they would recommend for your extraction. Perhaps you should mention the application you have for the extraction and how that might affect the creation process. Keep in mind that not every extraction needs to be the same.
Many of the shapes you see made out of metal get that way through a process called metal extrusion. The first extrusion process for pipe making was patented by Joseph Bramah in 1797. He made pipe out of soft metals forced through a die with the use of a hand-driven plunger. Bramah also invented the hydraulic press, used by Thomas Burr in 1820 to make lead pipe. The process was furthered in 1894, when extrusion with copper and brass alloys were used.
Metal Extrusion Process
The extrusion process is used to make objects with a fixed cross-sectional profile. There are two extrusion processes, cold and hot. The particular metal to be extruded is in the shape of a cylinder called a billet. The billet can be up to 72 inches long. The billet is heated higher than the recrystallization temperature, but before the melting point. A copper billet is heated to 1100 to 1825 degrees F. The melting point for copper is 1984 degrees F. The die is loaded into the press and is preheated to keep the billet from sticking. When the hydraulic pressure is applied, the billet is forced through the die, squeezing out on the other side in the desired shape. The extruded metal is then air or water cooled, and finished to the required length. The hydraulic presses are very big, ranging from 230 to 11,000 metric tons. The pressures they can apply range from 4,400 to 101,500 psi.
Types of Metals Used for Extrusion
The types of metals used for extrusion are lead, tin, aluminum, copper, zirconium, titanium, molybdenum, beryllium, vanadium, niobium, and steel. They all have different melting point and extrusion temperatures. Some of the custom copper extrusions are angles, channels, component parts, connectors, and contact substrates. Metals and alloys can also be made into round or oval tube shapes, hollow square tube shapes, channel shapes, Z shapes, T shapes, H or I beam shapes, and L shapes.
Benefits of Metal Extrusion
Parts made by extrusion may not have the same dimensional accuracy or surface finish as machined parts, but machine processes produce scrap metal waste. Extrusion is more cost-effective, and there is no need to dispose of waste material. More extruded copper shapes are rods, bars, custom shapes, hex bars, half rounds, and coil stock. Contact a copper extrusion supplier for a virtually unlimited variety of shapes, sizes, lengths, and alloys.
Examples of electrical contacts are breakers, relays switches, and electrical discharge machining applications. You use electrical contacts every day without even thinking about it. When you flip a switch, a light goes on or off, almost like magic. You know that electricity is flowing when the light comes on or you hear the refrigerator, furnace, or air conditioner running. Electrical contacts are something we just take for granted. We don’t know or don’t want to know how they work until something goes haywire.
Electrical Contact Material
Since the discovery of copper about 9000 BC, civilization has been technologically advancing in leaps and bounds. Copper is used for a multitude of items and applications, from household uses to copper tubing, copper wire, and water pipes. A breaker in a fuse box, for instance, has a plastic housing with metal components inside. The metals used in electrical contacts can be palladium, palladium alloy, silver, silver alloy, silver graphite, silver tungsten, and base metal or plated base metal. Spring material can be copper, beryllium, copper alloy, nickel, stainless steel, and steel. These metals can be plated with gold, nickel, silver, tin, or other metal. The metal used will depend on where the electrical contact is used or how big of a load it must carry. Electrical contacts need to be oxidation resistant and have a high conductivity rating. High-power equipment brushes where abrasion will occur, so the metal surfaces need to be made of strong alloys. Some metals that augment the structural properties, such as strength, weldability, toughness, temperature strength, and corrosion resistance, are tungsten, nickel, graphite, and molybdenum.
Electrical Contact Assembly
Soldering metals together is a common method when heat strength and load are not a concern. However, brazed electrical contacts are stronger and can withstand higher temperatures and heavier electrical loads. Brazing can join almost all metals. Transit electrical contacts need the extra strength provided by brazing, with high density alloys using silver or copper blended with tungsten or molybdenum. Brazing is used for electrical components, pipe fittings, and metals with varied thicknesses.
In the automotive industry, there are electromechanical switches, sensor devices, and many more. A multitude of electrical contacts, switches, and relays are used in power transmission and distribution, low to medium voltage electric and diesel electric transportation, AC and DC motor controls household appliances material handling, and rail signaling, to name a few. A tungsten contact supplier can offer you the best electrical contacts that will provide you with years of reliable service.
Electrical contacts are essential electronic circuit components in any device that controls the flow of electricity. Primarily found in circuit breakers, relays, connectors, and switches, contacts open and close the electrical circuit running through the device. When contacts are connected, the circuit is “closed” and able to carry current. Conversely, when contacts are separated by an insulating air gap, the circuit is “open” and interrupted.
Many standard and custom electrical contacts are comprised of conductive metals, such as nickel, copper, cadmium, and other various alloys. Although these materials are capable, they can and do degrade over time due to oxidation, corrosion, erosion, and heat. For this reason, many manufacturers apply a thin layer of gold plating with a nickel undercoating to protect their contacts and improve their capabilities.
Why Use Gold Plating?
You’re probably wondering why electrical contact manufacturers use gold plating; after all, the precious metal is expensive. However, gold has various physical and chemical properties that make it ideal for electronic applications. Here are some that make it a solid long-term return on investment.
- Better corrosion protection: Gold boasts an incredible resistance to oxidation, which produces corrosion; this makes it ideal for contacts exposed to corrosive environments or agents.
- Improved electrical conductivity: Corrosive environments and agents degrade metals commonly used in contacts, thus interfering with their conductivity. Gold doesn’t break down under these conditions and protects the contacts from corrosion and rust.
- Increased durability: Gold provides considerable protection from regular wear and tear like fretting, which is erosion caused by repeated rubbing and friction; this can considerably prolong a contact’s lifespan.
- Ease of application: An electrical contact requires just a very thin layer of plating—any excess coating will negatively inhibit its efficiency. Gold is an incredibly malleable metal, making it very simple to apply the proper amount of plating for each unique application.
- Excellent heat resistance: Gold’s properties make it a valid form of protection for contacts routinely exposed to high temperatures (>125°C/257°F).
When you have raw metals that you need turned into usable pieces, you have a few fabrication options. There are a lot of conventional techniques that get the job done. For instance, you may have your finished good machined from semi-finished casing products. However, these days, powder metallurgy applications are far more efficient for a variety of reasons, and they can help save your company money while getting the best possible products. Here are just a few reasons why powder metallurgy contact tips are more beneficial than the alternatives.
Since powder metallurgy manufacturers have a higher degree of accuracy than manufacturers of most other forms of fabrication, that means you can get repeatable results when you need products of the same size and dimension. When it comes to small components like contact tips, it’s especially important that everything is just the right shape and size. It’s also a factor to consider if you have any special requirements needed to make them most effective. For instance, you might need to change the porosity of the metal or alter it so that it has a lower melting point in order for your contact tips to perform well as they’re intended.
Powder metallurgy materials are often cheaper to buy than semi-finished materials. That means you’re starting off at a lower base price for purchasing powder metallurgy contact tips than when purchasing other types. This is because you can find raw materials more easily and because less work went into preparing them.
Because of the process accuracy, it’s easier to mass produce contact tips with powder metallurgy applications. That means that you can buy them in bulk, which often gets you company discounts. The production also process produces very little waste, which means you’re not spending on extras, and it’s a more sustainable option.
Overall, powder metallurgy contact tips provide heightened performance at a lower bottom dollar cost, which is music to the ears of manufacturers everywhere.
The differences between copper and aluminum contacts is probably not a topic at a dinner party, well, anywhere. It is, however, foremost on the minds of those who build electrical equipment, appliances, machinery and systems or if the person in question is an aluminum and copper extrusion supplier. To those people, the differences are critical to making sure whatever they are working on is a success. Here is a comparison of the two types of contacts and where each has the best application.
Aluminum weighs less than copper. Comparatively, it weighs much less. That makes it ideal for applications where overall weight is a factor. For example, aluminum is used in electric transmission and distribution lines because the lighter weight means fewer support towers are needed. In fact, most high-voltage wires are made of aluminum. The weight factor only plays a role with contacts many are used in the application or project. With space and footprint being a critical focus under most project management methodologies, aluminum or custom copper extrusions focused on weight reduction might be the preferred choice.
Aluminum carries about half of the current potential as copper. As such, copper is the better choice if the consideration is only electrical capacity per volume. Aluminum, however, carries more electricity if the key metric is capacity based on weight. Again, a copper extrusion manufacturer might be able to shed weight in the production process, but overall, aluminum is lighter, but has to handle a lighter load.
Practically, what all that means is that copper will be more resilient as a connector material, but aluminum offers less carry capacity, but could be the preferred choice if weight is the deciding factor. In applications where weight is of extreme importance, say in aviation, thousands of aluminum connectors versus the same in copper could make a defining difference. An example of when copper would make more sense is when the load the connector would be carrying was heavier than what an aluminum connector could carry if all other things were equal.
Longevity and Maintenance
It stands to reason that here again, load capacity is a deciding factor. If an aluminum connector will wear out quicker if exposed to a heavier load or if affected by dust, dirt and debris and change-out of components was an issue, copper is your better choice. If maintenance is not an issue or if the application has a high burn rate and thus the connector reliability does not matter, aluminum might be the better choice.
There are many factors that help determine if copper or aluminum connectors is the better option. Weight, load capacity and maintenance all factor in what you choose from your aluminum and copper extrusion supplier.
Your electric power system puts up with a lot of stress. If you’ve had the same system in your building for a while, then it’s important for you to routinely examine it and maintain it as necessary. Otherwise, you could end up having to replace part or all of the system, which is not only a huge expense, but is also a time-consuming project that can seriously inconvenience you until it’s all finished. A big part of your maintenance should involve your switching equipment, especially your switchgear auxiliary contacts.
Since you’re dealing with complex electrical systems and may not have the equipment or expertise to do it yourself, you may want to hire contact switchgear services to perform regular inspections. Whether you do it yourself or hire someone, this inspection should not only include a cursory visual inspection but also a more in-depth infrared inspection. This helps you find you find the loose connections that could cause problems later. When you perform these inspections, you may have to recondition old parts or even replace parts on occasion if they’re too damaged to use anymore. This may seem like a waste of money, but investing a little now can save you money later, since one damaged part can cause a series of problems throughout the system if left untreated.
Keep It Clean
As with most things, switchgear contacts perform best when clean. This means you should remove dirt, dust, and any other contaminants that might build up in the system. The contacts are exposed to a lot of moisture and heat as well as microscopic debris, so you should clean the contacts as necessary and protect them from further contamination as much as possible.
Exercise Your Breakers
One way to help keep your contacts clean is to exercise your breakers. Professional contact switchgear services can help you with this part, in case you’re worried about messing around with your system and potentially damaging something. Essentially, they will open the circuit breakers manually to keep everything moving freely and prevent any corrosive buildup that might interfere with the system. Ideally, this should be done once a year.
The copper extrusion process combines several phases to produce a high quality, customized, precision-oriented extrusions using state of the art machinery. From alloy selection through final reduction the process only works if it’s governed by the strictest quality control procedures available. Here’s an overview of the process.
In-House Copper Bar Mill
The extrusion process begins with billets produced in an controlled environment then cut to a precise size. The billet then goes into a high-speed induction billet heater. Once heated to temperature, the billet is placed into a 900-ton Loewy hydraulic extrusion press with a shuttle press capable of automatic bar pointing. Coming out of the press, the billet goes into an in-line cooling system to reduce copper oxide formation during the extrusion process. The next step is a 45-foot cold draw bench which allows for straightening and reduction of the extruded bar to their final sizes with precise hardness. The final steps are cleaning and packaging the bars for final delivery.
Guaranteed Quality and Production Control
Every chemical composition used is first assessed in the laboratory. If it doesn’t meet quality thresholds, it is rejected. This process makes sure the desired alloy composition is present before anything is extracted and because standard quality thresholds are high, it’s almost guaranteed that the client’s expectations will always be exceeded.
There’s also a check system utilized in the manufacturing process. This entails a physical and chemical check of every component. Finally, a Certificate of Compliance is available with every shipment, or if requested, that guarantees the quality standards of the materials used, alloy mixes and the final product. Additionally, full metal testing is available upon request.
To ensure that every job meets customer expectations in terms of cost and delivery, a computerized monitoring system allows for monitoring of scheduling, production cycle, overall and per unit costs and quality assurance check results. This ensures that every job is completed on time, on budget, and possesses the quality clients expect.
Depending on a client’s need, this process can produce full bar lengths, cut to precision lengths or fully machined pieces ready for an assembly process.
Specific shapes that can be fabricated include various angles, rectangular, round, square and hex bars as well as half rounds while guaranteeing quality and production consistency. Because it’s highly customizable, every client leaves satisfied with the custom shaped bars that are extruded to their precise measurements and requirements.
With their extremely high melting point of 4000° F, refractory metals are uniquely capable of withstanding heavy use under severe conditions. This property, as well as their high density and chemically inert characteristics, make refractory metals ideally suited for a number of industrial applications. Here are just a few instances of the way in which these remarkable materials can be utilized.
Refractory Metal Contacts
Any industrial use that requires constant wear at low to medium voltages is an ideal circumstance for refractory metals. Motor controls, power transfer switches, circuit breakers, push-button switches, wiring devices, and countless other examples of electrical contact assemblies make good use of the refractory metals’ toughness and durability.
Refractory Metals in Powder Form
The advantages of refractory metals – such as their exceedingly high melting points – means manufacturing can be a challenge. One technique to better utilize their characteristics while reducing cost is to apply refractory metals in powder form onto a base metal. By bonding an extremely thin layer of refractory metals onto a surface area of a cheaper metal, manufacturers can cut back on the amount of precious metal required to achieve the same advantages that come with standalone refractory metals. These powder metal contacts are only necessary at critical points, so the cost is reduced without any reduction in quality.
Silver has a high conductivity, so it’s perfect for electrical contacts. Besides the better conductivity, contacts made of silver alloys such as silver nickel, silver tin oxide, silver graphite, and silver tungsten are highly durable and low in environmental toxicity, making silver alloys the preferred contact used in many industrial situations.
Cadmium, unfortunately, is highly toxic and has gone out of fashion of late due to environmental concerns. Composed mostly of alloys such as silver cadmium oxide, the more reliable and safer alternative silver alloys are replacing cadmium in most modern applications.
The durability, reliability, and low cost of refractory metal contacts – as well as the decreased environmental impact of new silver alloys – has led to their increased demand in the world of industry and manufacturing for the present and for the indefinite future.