Although aluminum, ferrosilicon, silicon carbide, and even coke have also been used for this purpose, calcium carbide has proven to be more economical, more efficient, and more reproducible in its effects. This is due to the fact that unlike the other materials, calcium carbide produces CO gas which uniformly distributes and mixes the carbide while foaming the slag; does not require a balancing lime addition as do silicon-based additives (in fact every pound of carbide adds about one pound of lime); reacts exothermically (producing heat) to not chill the slag; and under typical conditions does not dissolve in steel producing practically no carbon pick-up, no unexpected deoxidation, and nearly 100% utilization.

In addition, the reaction of carbide with oxides produces a large amount of heat that is highly retained in the process. This has efficiency implications for ladle metallurgy, but moreover carbide provides major cost savings as a source of energy and productivity improvement in the steelmaking furnace.

Once you have determined what feed and speed to start with, there are other factors to be taken into consideration. The next thing to be considered is the direction of the cut, which is the direction the cutter is fed into the material. Conventional milling or cutting forward is the most commonly used method.  With this method, the work is fed against the rotation direction of the cutter. The other method is climb milling or cutting reverse. For this machining method, the workpiece and the machine must be rigid. When machining non-ferrous materials, climb milling should be used to achieve a good finish.

Carbide end Mill RPMchart

A co-product of the acetylene generation process, calcium hydroxide is extremely useful in a variety of industrial applications. Perhaps the most famous use of our calcium hydroxide is in the scrubbing of stack gases from fossil-fueled power plants to remove sulfur compounds before release to the air.

In every case, consistent carbide purity and sizing are of special importance, especially with respect to oversize and fines.

If you are running at 18000 RPM using a 25mm cutter with two flutes, and a recommended chip load of 0.1 mm/tooth:Feed = 2 x 0.1 x 18000 = 3600 mm per minIf the RPM were increased to 24000 RPM the new feed rate would work out to be:Feed = 2 x 0.1 x 24000 = 4800 mm per min

HSS End mill SpeedsandFeedsChart

To obtain the optimum Chip load, you must consider these variables, along with the machine and materials you intend to cut. This will help you find the best feed rate and RPM for any given tool and material.

Aluminummilling speed chart

In addition, steelmakers use calcium hydroxide to neutralize waste pickling acid, and chemical manufacturers to neutralize waste streams; while municipalities use it to treat sewage and builders to make sand-lime brick. Carbide Industries is a major supplier of this product, which is available in both dry and slurry forms.

Calcium carbide is converted into acetylene in a controlled reaction with water using an apparatus called a generator. Acetylene, which has the chemical formula C2H2, is an extremely useful hydrocarbon due to the energy that is locked up in the triple-bond between the carbon atoms. This energy is then released and utilized in different ways by our customers for a variety of industrial purposes.

Because of their reactivity, calcium carbide powders are manufactured, mixed, loaded, and transported in either 20 ton pressure differential trailers or 90 ton railcars, under an inert nitrogen atmosphere.

Millingspeedsandfeedschartpdf

For subsurface injection, a powdered carbide is manufactured by ball milling selected sizes of carbide to less than 140 US-mesh (<105 microns). The milled carbide can then be custom blended with a wide range of other powder additives, such as lime, limestone, and fluorspar to meet customer specified formulations. The milled carbide is treated with special additives to significantly improve flow characteristics.

Carbide Industries manufactures three standard sized products for ductile iron desulfurization, generally within the range of 8 to 80 US-mesh (2.5 to 0.2 mm). In addition, two patented specialty products are available to meet specific customer requirements. These specialized products are formulated to help eliminate the retention of unreacted carbide in the resulting desulfurization slags and also to minimize slag odor.

Lathe cuttingspeed chartPDF

End Mill SpeedsandFeedschart

As late as 2002, most blast furnace iron was desulfurized in the torpedo car as shown above. In the integrated steel mill, this practice has now been largely replaced by the use magnesium to remove an initial amount of sulfur in the transfer ladle, and the use of carbide as a steel ladle deoxidizer and slag conditioner to obtain the final sulfur specification.

For this application, Carbide Industries can provide the grade size of calcium carbide that best meets the requirements of a particular application. Standard sizes range from 0.5" x 0.25" (13 mm x 6.5 mm) to 10 x 40 US-mesh (2 mm x 0.4 mm). For increased ease of application, these grades are available in smaller 2 1/2 and 5 gallon containers, in addition to the conventional 55 gallon drums and 2.5 ton bulk flo-bin containers.

When carbide is reacted with water to produce acetylene, it produces calcium hydroxide, itself a useful chemical. Having a pH of 12.4 and a ready reactivity with sulfur, it is widely used for acid neutralization, pH modification of soil, and for the cleaning of sulfur emissions from industrial processes and power generators.

Calcium carbide is a powerful and effective chemical reducing agent, and can also be used as a source of energy. Nowhere is this more evident than in the field of metallurgy, where it is used in several ways to reduce costs.

For furnace injection, Carbide Industries produces carbide in a size range suitable for pneumatic transport to the furnace, where it is blown into the furnace with inert gas. Carbon injection ports that are marketed by several companies are entirely suitable for carbide injection. Carbide Industries LLC has also certified pneumatic equipment vendors that have the know-how to manufacture the tranport equipment. (Pictured is a MOCA pneumatic injector/transporter modified for use with calcium carbide produced by More s.r.l.)

In modern steelmaking operations, the need for lower sulfur steels demanded by modern continuous casting operations and specialty applications has increased calcium carbide's appeal as a hot metal desulfurizer or as a modifier to the slag to increase desulfurization efficiency.

Acetylene derivatives are used in a variety of everyday consumer products, including hair sprays, cosmetics, tabletted drugs, sun screens and lotions, antiseptics, and tartar-control toothpastes. In addition, acetylene intermediates provide the basic feedstock for the production of polyurethane fibers, synthetic rubber, perchloroethylene (a widely used dry cleaning solvent), trichloroethylene (a degreasing solvent used in metal working processes), and a new type of refrigerant gas which is designed to replace the environmentally damaging chlorinated fluorocarbons (CFC's) currently in widespread use.

An acetylene cylinder for cutting and welding purposes is perhaps the most recognizable use, but many important chemicals are derived from acetylene.

- Cut too deep in a single pass. Sometimes it can be more efficient to use a higher feed rate and two or more passes rather than a single cut at a low feed rate

Carbide is an essential tool for the removal of unwanted iron oxide from furnace slag that is carried into the ladle during tapping. When added to the liquid metal stream, or to the ladle after tapping, a coarser grained carbide reacts with the oxides and recovers iron and expensive alloys that otherwise would have been lost. Furthermore, left untreated, these oxides can interfere with the downstream steel refining operation by inhibiting desulfurization, oxidizing ("fading") alloy additions, and attacking refractories.

Purity and particle size are the key parameters for optimum effectiveness in these applications. Particle sizing is carefully selected to provide maximum contact with carbide particles without incurring excessive dust losses.

Therefore depending on the diameter of the tool, if the RPM and number of cutter edges stay the same chip load will increase with a larger diameter cutter, thus the feed rate will also increase. When machining softer materials or using a stubby router bit the chip load can be increased. If an extra long router bit is being used, the chip load should be decreased.

While calcium carbide is utilized directly as a process material, its major use and perhaps its greatest versatility is realized when the rock-like substance is reacted with water to produce acetylene and calcium hydroxide. The unique chemistry of the triple-bonded carbon in the acetylene molecule allows for a variety of useful chemical reactions to form intermediates which are used in the manufacture of a diverse range of chemical derivatives.

In ductile iron foundries, liquid iron must be desulfurized before specialized inoculation treatments can be employed. This desulfurization is frequently performed by feeding granular forms of calcium carbide onto the surface of the liquid iron, which is contained in specially designed mixing units.

Speedsandfeeds formula

In modern steelmaking operations, the need for lower sulfur steels demanded by modern continuous casting operations and specialty applications has increased calcium carbide's appeal as a hot metal desulfurizer.

- Forget that doing some test cuts on a spare piece of material is a good way of checking settings before running your main program

When calculating the feed rate for any material the chip load is therefore one of the most important factors to be taken into account because the chip load determines the amount of material that each tooth will remove, plus the load that each tooth will have to take. Another factor that affects chip load is the diameter of the cutter. A larger cutter will be able to handle a larger chip load.

Even though there are formulas for calculating feed rates you will find that the optimum feed rate will be determined from experience. You will typically start off with the calculated feed rate. Under ideal conditions, it is usually suggested that the actual feed rate be set to approximately one-half the calculated amount and gradually increased to the capacity of the machine and the finish desired.

Carbide Industries LLC generates large volumes of acetylene at the Calvert City, Kentucky, plant for distribution via pipeline to several specialty chemical manufacturers.

Based on this equation, as RPM increases, the feed rate will also increase if all other settings remain the same. If the number of cutting edges changes, however, the feed rate will either increase or decrease depending on whether the number goes up or down. The same applies to chip load if the recommended chip load is 0.1 mm/tooth the RPM, feed or number of cutting edges may go up or down to maintain the required chip load. Therefore if the chip load remains the same, and the feed rate increases, either the RPM and or number of cutting edges must increase to maintain the recommended chip load.

In addition, since most of the slag that is generated in the EAF is not tapped into the ladle, all of the benefits of oxide reduction and alloy recovery that are well-known in ladle metallurgy are available to the EAF on a much larger scale.

Carbide Industries LLC provides calcium carbide to both large national distributors of industrial gases and to numerous smaller, independently owned businesses, which generate acetylene for cylinder filling at locations throughout the US, Canada, and the Caribbean.

At Carbide Industries, calcium carbide production in different sizes (grades) is all we do. Generally speaking, the different grades of carbide that we make correspond to different reactivities of the carbide. For example, we produce fast-acting carbide powder that is injected into molten iron to combine with and remove sulfur. We also supply carbide in a slower-reacting nut size to add to the stream of molten metal when the steelmaking furnace is tapped. The carbide reduces oxides and returns iron and metal alloys to the steel that would otherwise be trapped in the slag, but does not react so fast that the steel overflows its ladle.

These often provide a good starting point but can usually be further improved through a small amount of trial and error. Most machine controllers allow you to adjust the feed rate while a program is running and by listening to the sound the cutter makes this can be a good way of optimizing the parameters.Feed rate is calculated using the following equation:

N = number of cutting edges (flutes)T = chip load (chip per tooth) is the amount of material, which should be removed by each tooth of the cutter as it rotates and advances into the work (mm per tooth)Z = RPM, the speed at which the cutter revolves in the spindle (Revolutions per minute)We will now break down the relationship between the Feed rates, number of cutting edges, chip load and RPM. For most materials, there is a recommended chip load.

Among the many uses of acetylene gas, the largest and perhaps the most familiar is its use in the form of cylinder gas for metal fabrication and construction. When combined with oxygen in an oxyacetylene torch, acetylene produces a flame temperature in excess of 6,000 degrees F, the hottest flame of all hydrocarbon gases. This provides the means to cut or join many types of metal, cleanse them of surface imperfections, and strengthen them through flame hardening. In addition, acetylene is lighter than air and is therefore the safest fuel gas to use in confined spaces, below ground, or on ships.

Another factor is depth of cut. Depth of cut will affect edge finish as well as tool life. You will have to adjust your depth to achieve the desired results depending on the type of material and size of the cutter. Usually, a depth of cut that equals the radius of the cutter is a good starting point when cutting non-ferrous metals.

When material is machined the cutter must revolve at a specific RPM and feed at a specific feed rate to achieve the proper Chip load. There are also several factors to be considered when choosing the proper RPM and feed rate.

For most material that you will be cutting on a CNC router you will typically set the RPM between 12000 and 24000, and adjust your feed rate to obtain the required results. The speeds and feeds chosen can be affected by the power of the spindle being used. Higher power spindles will produce more torque thus allowing the machine to run at a variety of RPM’s (torque drops off as the RPM is reduced).

Carbide has the unique ability to react only with metal oxides without adversely affecting steel chemistry, adding significant amounts of energy to the process. In the electric arc furnace (EAF) the energy produced during the oxide reduction is accompanied by the production of heated lime particles and CO gas which assist in retaining the heat generated while adding to the ability of EAF slags to foam.

MillingspeedsandFeedschartMetric

One thing to remember is to make chips, not dust. Chips will help by removing the heat produced in the cutting process thus increasing tool life and improving edge quality. Feeds and speeds are usually all set in the programming software that is used to create the machine program. There are many resources available to help determine suitable settings for particular material/router bit combinations.

The best way to choose which grade you need is to contact us. Our industry experts have decades of experience specifying carbide grades for different applications and optimizing processes in many industries.

Calcium carbide is converted into acetylene in a controlled reaction with water using an apparatus called a generator. Acetylene, C2H2, is an extremely useful hydrocarbon due to the energy that is locked up in the triple-bond between the two carbon atoms. This energy is then released and utilized in different ways by our customers for a variety of industrial purposes.

The feed rate used depends upon a variety of factors, including power and rigidity of the machine, rigidity of part hold-down, spindle horsepower, depth and width of cut, sharpness of cutting tool, design and type of cutter, and the material being cut.

Calcium hydroxide is easily spreadable and sprayable over large tracts of land. In this way farmers use our carbide lime to neutralize the affects of acid rain, and mines use it to neutralize acidic water runoff. In the right amount, the fine size and reactivity of our calcium hydroxide causes a chemical reaction with soil similar to the formation of concrete. This soil stabilization reaction is used in the road construction industry as it forms a very stable sub-roadbed surface for our roads and highways.