Introduction of Wet Pan Mill: Wet pan mill is mainly applied to all kinds of non-ferrous metals, ferrous metals (example: gold, silver, copper, lead, zinc, tungsten, molybdenum, iron, manganese minerals...) grinding operation, assembly of large tonnage grinding wheel, has characteristics of large capacity, high efficiency and operation index stability, etc. The machine assembly of the latest research and development large torque WS type horizontal speed reducer, grinding wheel, rolling plate adopts special casting workpiece, seiko design, durable, low noise, low loss, less investment, quick effect, etc. It is the optimal choice for grinding equipment of small and medium-sized dressing plant. The Working Principle of Wet Pan Mill: The equipment mainly include power plant, frame, grinding wheel, pan mill... parts, adopt grinding wheel dynamic type grinding works: First of all, motor will power transmission to the reducer, under the speed reducer drive, through the large vertical spindle transfer torque to the upward side cross shaft, pass through installed on both ends of the horizontal axis of the pull rod to grinding wheel, make the wheel produces driving force, along the horizontal axis horizontal do counterclockwise motion; Grinding wheel at work can be both around the wet pan mill large vertical shaft orbit, and around the central axis of wheel rotation, Pan mill is stationary. Add the mineral materials, within the mill from the extrusion wheel of its own weight, grinding wheel with the pan during the revolution and rotation produce the enormous friction, by repeated after extrusion, kneading, grinding, were crushed. Grinding wheel in rolling and kneading minerals at the same time, both mixing mud making function, the material fully mix with water, make each grinding index stability such as pulp density, After grinding crushed the monomer dissociation mineral fine grained, in the pulp of hybrid, was taken to the upper level, the Settings on the basin of the overflow mouth nesting, the overflow discharge, into the next operation process, coarse mineral sedimentation on the bottom of the pan, continue to grinding and crushed, until the fineness of up to standard; Set in basin discharging mouth mesh screen(screen mesh, shall, depending on the type of mineral separation requirements, reasonable set), can strictly control the grading granularity, avoid even the appearance of uneven thickness of mineral grinding or particle size, create favorable conditions for subsequent operations. In the grinding process, should fully follow the principle of more crushing and less grinding: as much as possible use crushers to reduce the materials' particles size, materials into edge runner comprehensive granularity reduce, improving the mill machine efficiency, reduce beneficiation plant overall loss. Our wet pan mill has high yield, good stability, can adapt to a variety of non-ferrous metal ores, ferrous metal ores, non-metallic minerals, is the first selected grinding equipment for small and medium beneficiation plants and coal pulverizing plant. Technical Parameters of Wet Pan Mill: Wet Pan Mill machine safety operation: 1. operator should be trained qualified by manufacturers, fully understand the device structure and performance, then can take up his quarters to operate the machine. The operator should comply with the relevant safety, shift system. 2. before working, in strict accordance with the provisions add oil and maintain the proper fuel, oil line is smooth, oiling mouth is clean. 3. Check the circuit, electrical parts, wiring connectors, whether switch is securely intact. If damaged, must repair and replacement. 4. Check that whether the various parts of the machine is intact, whether the runner wheel is flexible, drive belt's degree of tightness, whether transmission parts are securely connected; after checking, boot idling for 3-5 minutes to ensure every part normal, then add ore and should be in strict accordance with specified amount, it is strictly prohibited to work overload. 5. when feeding, materials should be sieved to prevent iron ore and other hard metal debris into the mill and damage the machine. 6. when shut down for any reason, first remove the materials in the grinding pan, then restart, strictly prohibit to forced start. 7. when the device is operating, operators shall not leave, should make an inspection tour for every part working condition. If the device send out abnormal sound, runner wheel large amplitude vibration, reducer oil temperature is too high, motor's enclosure is overheating, drive belt skid, should immediately stop and dispose. 8. in shutdown process, when the grinding wheel is s not completely stopped, forbid arms and other devices into the grinding basin, prevent to hurt people, damage to the machine. 9. pelple wnter into the grinding basin to repair, in addition to disconnect power switch, put up warning sign with "someone overhaul, not allow switch on", and set the specialist care to avoid touching. 10. after maintenance, should examine, sweep the device, remove sundries, and every switch set neutral position, then open power switch. 11. during usage, should comply with maintenance principle of regular maintenance every day, seven days little maintenance, monthly maintenance, to make the machine safety and efficient production.
Ball mills are a similar shape to that of the rod mills except that they are shorter with length to diameter ratios of1 to 1.5.As the name implies, the grinding media in these mills are steel balls.The particles size of the feed usually does not exceed 2.5 cm.The grinding is carried out by balls being carried up the side of the mill such that they release and fall to the point where they impact the ore particles in trailing bottom region of the slurry.If the mill is rotated too fast, the balls can be thrown too far and just strike the far end of the mill and conversely, if the mill is rotated to slow, the efficiency of the grinding process significantly reduced. Ball mills are suited for finer grinding as larger particles do not impede the impact on to smaller particle as in rod mills.
Detailed Product Description: Ball mill is widely used for milling various kinds of ores or rocks in metal and non-metal mining and building material industry.The main bearing of the ball mill with the shell diameter 900-2100mm is spherical liner bearing; for the shell diameter 2700mm,the main bearing is completely closed self-aligning 120,bearing withBabbitt alloy of high lead and low tin with low hardness,underneath laid withcooling copper piping full of water The bearing is of static pressure structurewith high and low pressure united oil lubricating system. Our Ball Mill is the key equipment for grinding after the crush process, which is widely used in the manufacture industries, such as cement, silicate, new building material, refractory material, fertilizer, ferrous metal, nonferrous metal and glass ceramics and can be used for the dry and wet grinding for all kinds of ores and other materials able to grind. The Ball mill Model: 1830*3000,1830*6400,1830*7000,2200*5500,2200*6500,2200*7500 Weight of ball mill:112325,30,30,23.
Ball mill is the key equipment for secondary grinding after crushing. And it is suitable for grinding all kinds of ores and other materials, no matter wet grinding or dry grinding. Besides, it is mainly applied in many industries, such as ferrous&non-ferrous metal mine, building materials, chemical, electric power, coal, traffic, light industry, etc. In our company, this series of high-efficiency ball mill adopts rolling bearing support instead of sliding bearing support with bearing bush. Therefore, it can save energy by 10-20%. According to different discharging ways, it can be divided into two kinds, grate type and overflow type.
Ball Mill Quick Details Condition:New Type:Ball mill Capacity(t/h):0.65-615t/h Place of Origin:Henan, China (Mainland) Brand Name:Hongxing Model Number:Refer to specifications Certificate:ISO9001:2008 Color:Orange Motor power:18.5-4500kw Weight:5.5-525t Warranty:1 Year Feeding granularity:not more than25mm Discharging granularity:0.074-0.89mm Ball load:1.5-338t Shell rotation speed: 13.8-38r/min FOB Price:US $7,936 - 676,200 / Set Port:Qingdao, Tianjin, Shanghai, Lianyungang or others Minimum Order Quantity:1 Set Supply Ability: 100 Sets per month as request Payment Terms: L/C, D/A, D/P, T/T, Western Union Packaging & Delivery Packaging Detail:Standard container, or in bulks, bare main machines, motors and small parts are packed in wooden cases. Delivery Detail:25 Working Days after placing the order Specifications 1 .Large capacity mill 2. Longer lining service life 3. Wide application Company Profile Henan Hongxing Mining Machinery Co., Ltd. is a joint-stock mining machinery manufacturing enterprise integrated in scientific research, production and marketing. It is located at the High & New Technology Industries Development Zone of Zhengzhou, China with an area of 50,000 m2 which includes 15,000 m2 of standard heavy duty industrial workshop. Equipment are more than 160 pieces, including large and medium sized metal processing, riveting and installing equipment. There are 960 workers including 80 administrators with secondary and senior occupational titles and engineering technicians. Research and Marketing In order to promote competitive strength, advanced technologies have been introduced from America, Germany, Japan and Australia to establish international advanced production line, first-class modern testing base as well as research centers of stone crushing, sand making, milling and ore dressing equipment. Scientific management, advanced processing technology and innovative manufacturing theory make the company become the most renowned manufacturing and exporting base in China. Now we have tens of thousands of users from throughout China and more than 30 world markets, such as: Africa, Middle East, Eastern Europe, Southeastern Asia and South Asia. Honors and Awards In 2001, Hongxing Brand mining machinery has passed the authority test detected by the State Department and been rated as 'Products with Standard quality and Assured brand'. In December 2003, we obtained the certificate of ' Qualified Products' by the National Quality Inspection. In April 2005, Hongxing Brand is rated as 'Chinese famous brand'. All products have passed the authentication of ISO9001. In addition, we have been awarded 'Civilized Enterprise', 'Key Enterprise', 'Enterprise with Standard Quality' and 'Enterprise with Honesty and Credit Standing' successively. Commitment 1. We guarantee that our products are all up to standards set for mining machinery. 2. We will deliver products timely by contract. 3. We will supply you with installation drawings, specifications and operation manual. 4. Lifetime warranty and components for products. Pre-sales Service 1. Model selection 2. Design products designated by clients 3. Our engineering and technical personnel can provide customers with technological process and project on site. In-sales Service 1. Product acceptance 2.Help formulate construction scheme for clients After-sales Service 1.Specialized post-sales service staff will instruct installation and debugging on site 2.Installation and debugging 3.Train technical staff for clients on site If you want to know much more information about our products and company, you can visit the following website: http://www.hxjqchina.com.
ReliableBall Mill Description: the key equipment for grinding after the crush process, and it is widely used in the manufacture industries, such as cement, silicate, new building material, refractory material, fertilizer, ferrous metal, nonferrous metal and glass ceramics, it also can be used for the dry and wet grinding for all kinds of ores and other grind-able materials ReliableBall Mill Working Principle: The ball mill is horizontal cylindrical rotation device, driven by brim gearwheel. There are two chambers and grid. Material goes into the first chamber through the feeding inlet. Inside the first chamber, there are stage liners and ripple liners as well as steel balls. The shell rotates so as to generate eccentricity, and this force brings ball to a certain height and then balls drop down by gravity, the impact is the grinding force to the material. After the primary grinding, materials go into the second chamber through segregate screen. In the second chamber, there are flat liners and steel ball. After the secondary grinding, material is discharged from the discharging mouth. Then the whole grinding process is ended. ReliableBall Mill Structure: The machine is composed of feeding part, discharging part, turning part and driving part (reducer, small driving gear, electric motor and electric control). The quill shaft adopts cast steel part and the liner is detachable. The turning gearwheel adopts casting hobbing process and the drum is equipped with wear-resistant liner, which has good wear-resistance. The machine is with stable and reliable working condition. Moreover, according to different materials and discharging methods, there are dry ball mills and wet ball mills for choice.
Ball Mill grinds material by rotating a cylinder with steel grinding balls, causing the balls to fall back into the cylinder and onto the material to be ground. The rotation is usually between 4 to 20 revolutions per minute, depending upon the diameter of the mill. The larger the diameter, the slower the rotation. If the peripheral speed of the mill is too great, it begins to act like a centrifuge and the balls do not fall back, but stay on the perimeter of the mill. The point where the mill becomes a centrifuge is called the "Critical Speed", and ball mills usually operate at 65% to 75% of the critical speed. Ball Mill Application: are generally used to grind material 1/4 inch and finer, down to the particle size of 20 to 75 microns. To achieve a reasonable efficiency with ball mills, they must be operated in a closed system, with oversize material continuously being recirculated back into the mill to be reduced. Various classifiers, such as screens, spiral classifiers, cyclones and air classifiers are used for classifying the discharge from ball mills. Ball mill is an efficient tool for grinding many materials into fine powder. The ball mill is used to grind many kinds of mine and other materials, or to select the mine. It is widely used in building material, chemical industry, etc. There are two ways of grinding: the dry process and the wet process. It can be divided into tabular type and flowing type according to different forms of discharging material. Ball Mill Features: 1) is an efficient tool for grinding many materials into fine powder. 2) The ball mill is used to grind many kinds of mine and other materials, or to select the mine 3) Ball mill is widely used in building material, and chemical industry. 4) There are two ways of grinding: the dry way and the wet way. 5) Ball mill can be divided into tabular type and flowing type according to differentexpelling mine 6) To use the ball mill, the material to be ground is loaded into the neoprene barrel that contains grinding media. 7) As the barrel rotates, the material is crushed between the individual pieces of grinding media that mix and crush the product into fine powder over a period of several hours. 8) The longer the ball mill runs, the finer the powder will be. 9) Ultimate particle size depends entirely on how hard the material you're grinding is, and the time how long the ball mill runs. 10) Our ball mills have been used to grind glass, powder food products, create custom varnishes, make ceramic glaze, powder various chemicals. 11)Complet ely enclosed welded design in high-grade steel. - Direct drive via bearing journal with top-mounted gearbox. Motor connected to gearbox via a V-belt drive. - Product discharge via slots located around the periphery of the drum. Ball mill Working Principle: The ball mill is a horizontal rotating device transmitted by the outer gear. The materials are transferred to the grinding chamber through the quill shaft uniformly. There are ladder liner and ripple liner and different specifications of steel balls in the chamber. The centrifugal force caused by rotation of barrel brings the steel balls to a certain height and impact and grind the materials. The ground materials are discharged through the discharging board thus the grinding process is finished. Standard export container or as your required.
Ball mill is mainly composed of charging and discharging, cyclone and rotation parts (like redactor, minor rotation gear, motor, electric machine, etc). Hollow axis is made of steel parts with a lining replacable. Major rotation gear, machined by rolling wheel of casting, is lined with wearing plate with fine wear-resisting property. This machine runs stably and reliably. the ball mill technical specifications from Dia 900-Dia 3200mm. Export standard container, or in bulk carrier.
Ball mill is the key equipment for grinding after the crushing process.It is widly used in the processing of cement, silicate, new building material, refractory material, fertilizer, ferrous and nonferrous metal, glass as well as ceramics. It is used to grind dry or wet ores and other materials of grindability. Feeding size(mm)
The low speed transmission is convenient for maintenance and starting.And the oil mist spray lubrication device ensures the reliable lubricating of big and small gears.Generally, the main motor of the large mill is high pressure asynchronous motor or synchronous motor.So customers should indicate the motor type in order.
Ball mill is an important grinding mill for grinding after materials are crushed and also an efficient tool for grinding various materials into fine powder.There are two ways of grinding: the dry process and the wet process. Ball mill can be divided into tabular type and flowing type according to different forms of discharging material.
Whiteside Machine Company began manufacturing router bits for the thriving furniture industry that existed in Hickory, NC. Through word of mouth, hard work and a focus on quality, our product line evolved and expanded to supply businesses and hobbyists throughout the United States. Made from high quality steel and tipped with micro-grain carbide, our years of experience provides you a full line of router bits your workshop will cherish.
Spiral router bits were originally designed for the CNC industry as a tool for long-life under intense working conditions. As spirals became popular with the everyday woodworker and craftsman, an increase in demand was seen throughout the industry. Whiteside offers a variety of spirals in up-cut, down-cut, and compression flute configurations. We recommend up-cut spirals for best control of your router and ejecting chips up and out of your dado cuts. Down-cuts provide superb control of fraying on the surface nearest the router while preventing the tendency to lift small workpieces. Compression spirals have up and down flutes to maintain the cleanest cut on both the top and bottom of the workpiece. Whiteside increases the life and value of your spiral selection by offering these bits in a solid carbide form.
Whiteside is proud to supply the industry with our superior line of drilling and boring tools. We offer a range of countersinks manufactured with standard carbon steel or superior high speed steel for extended life. Three wing drills and patented carbide-tipped hole saws are among our line. Many of these tools were designed and tested by consulting experts in the marine industry.
A standard router bit begins as no more than a piece of steel. Steel is purchased in 12-foot long bars and self-fed into a machine that cuts them to the appropriate length. As the cylinder-shaped pieces are cut, they are gathered and sent to the lathes.
The lathes run each piece of steel with precision accuracy to shape the general form of the bit and create the shank. Every size and type of router bit has a program to provide the specifications of the tool being manufactured. The shaped piece of steel - or a blank - is then sent to the mills.
The final step in manufacturing a router bit is to sharpen the carbide. Each piece of carbide is ground by hand so that the sharpest edge can be formed. The finished bit is then sent to the shipping department for final assembly and dipped in a protective wax covering.
Blow job, fellatio, giving head, going down: whateveryou call it, it doesnt take a PhD in anatomy to understand why receiving oral sex if you have a penis might feel amazing. The warm and wet sensation of a mouth on the nerve-dense shaft and head of a penis, combined with the sounds and visual of the act, can be crazy pleasurable.
On the one hand, your partner has the power to thrust into your mouth and throat, but on the other, you have all the power, as your teeth are in close proximity to their most sensitive parts, sexologistJessica "Dr. Jess" O'Reilly, PhD, host of the Drive Him Wild With Pleasure video course, tells Health. And then theres the thrill of watching your partner receive pleasure, she says.
Sincegiving and getting a blow job both have benefits, it pays to pick up some pointers for making blow jobs even more comfortable, exciting, and orgasmic. These are the top tips from Dr. Jess andboard certified sexologistLanae St. John, author of Read Me: A Parental Primer for The Talk.'
You probably know this, but blow jobs dont literally entail blowing on the penis, say, the way youd cool off soupunless your partner likes that. Instead, Dr. Jess tells Health that blow jobs typically incorporate some combination of licking, sucking, kissing, deep-throating, and hand action. Every person has their own preferences, so its less about technique and more about asking what they like, she says.
If you can come right out and ask your partner about their preferences, that's probably easiest. But sometimes giving a blow job is more of a fact-finding mission, and you have to try things out and gauge your partner's response. Dr. Jess recommends trying this: tuck your lips under your teeth, "clamp down for extra pressure, and then slide up and down the shaft."
Another tip: Flickyour tongue against the tip of penis, or along the frenulumthe sensitive notch of skin on the underbelly of the head. Based on your partner's response, you'll be able to see if they enjoy light pressure here, and if it's okay to advance to putting the entire head in your mouth...or if they prefer that you focus more on the shaft.
Theres a misconception that you have to be able to deep-throat to give an enjoyable blow job. But thats not true, says Dr. Jess. If youre nervous about gagging, not enjoying yourself, or uncomfortable, this will affect your lovers enjoyment. If you are going to try taking the head and shaft in your mouth but are worried about gagging, just go slow, and stop at any point you feel that gag reflex kicking in.
A blow job isn't all about the mouth. In fact, adding hand moves introduces a different level or pressure and sensation, magnifying the pleasure your partner is already feeling. It's also a good go-to if deep-throating isn't your thing. Using your hands to stroke the shaft while using your tongue and lips on just the tip, will create a similar sensation, she says. This is also a good tip for when your mouth or jaw gets tired...just switch to making a fist around the shaft and moving it up and down, or cup your partner's balls in your hand gently.
The testicles are incredibly nerve-dense, says Dr. Jess. Try creating a sucking sensation against the delicate skin with your mouth, or using your hand to massage the balls to wow your partner, she suggests.
You can also lick or caress the perineum, the area between the testicles and the anus. (Not everyone likes action here, so ask first or go very slowly.) Applying pressure here with your thumb or the flat edge of your tongue can stimulate the prostate, which is often called the male G-spot because of how intense stimulation here can feel. Try using a vibrating toy against this spot, suggests Dr. Jess.
You can also stimulate your partner's anus while youre giving a blow job by using a finger or tongue,says Dr. Jess. Some people get squeamish about having their anus played with, so get explicit permission before incorporating rimming or anal fingering. But if your partner consents, trust, youll blow their mind.
There's more than one way to give a blow job besides on your knees or with your partner lying flat. Your partner can lie back with their legs up or with bent knees. Or have them lie on their stomach with their hips up and legs out slightly, as you crouch behind them and treat them to a from-behind blow job.
Dr. Jess recommends "the giraffe," which entails you lying on your back with your head hanging over the bed and your partner straddling you from a standing position. You can also try "facesitter," she says, which hasyou lying on your back and your partner kneeling over your lips.
Its a myth that spitters are quitters. There is zero pressure to swallow if thats not something you want to do, says Dr. Jess. Maybe it's because you dont like the taste of semen; maybe you find it hotter for your partner to orgasm somewhere else on your body. Any reason is a valid reason, she says.
If you dont want to swallow, you have a few options. You can tell your partner where you want it (for example, I want it all over my chest or I want to see you finish in your hand"), you can catch the semen in your mouth and then spit it into atowel, or you can ask your partner to wear a flavored condom.
If you do want to swallow, Dr. Jess has a few suggestions to enhance the experience. Take the penis deep into your throat and when they come, gaze seductively into their eyes, she advises. Orwhen your partner tells you theyre close, suck only on the head, so you can control how much you swallow at a time.
Mutual pleasure is always a win in the bedroom. While giving a blow job, ask your partner to turn you on, too: have them talk dirty to you or tell you what they're feeling, or suggest bringing a vibrator or vibrating ring into the mix, which you can press against your clitoris or put in your vagina so you're both moving closer to orgasm.
And above all, always follow the number one rule of blow jobs: only give one when you want to and your partner wants you to. You are not obligated to give anyone a blow job or perform any act you dont want to, St. John tells Health. Any partner who makes you feel obligated to give one probably isnt a keeper. There are plenty of other acts and activities you can engage in to experience (mutual) sexual pleasure, says St. John. True that!
For a certain kind of handy geek, the journey is way more fun than the destination. Thats why Patrick Hood-Daniel, founder of buildyourcnc.com and author of the DIY CNC bible Build Your CNC Machine, was able to start a business that caters specifically to everyone who yearns to build their own router or milling machine from scratch.
CNC stands for Computer Numerical Control; the machines are usually platforms that allow a computer-driven cutting tool to carve a material in all three dimensions. CNC routers can be programmed to make precise, repeatable cuts on flat or low-elevation wood or plastic projects, while CNC mills turn blocks of steel or other materials into engine components, brackets, and otherincredible metal creations. For the truly hardcore, CNC is being applied to plasma and laser cutters, as well.
So after spending hours assembling (and admiring) the star of your home workshop, do you actually know how to use it? We asked Hood-Daniel for a few tips on how to handle common CNC operational hiccups.
To keep a part steady while being routed, many people insert holding tabs in the pattern. The tabs act as tiny bridges that hold the milled part to the stock material. The number of tabs depends on the part that youre cutting. There is a balance between using more tabs than necessary, and not enough, said Hood-Daniel. Not enough, and the tabs can snap during the milling process. More than necessary, and you waste much of your time breaking them away after the job is done.
When holding tabs wont do the job, use holding screws instead. Drill two or more holes into the part to be cut, and manually screw these holes to the spoil board (the sacrificial material supporting your project from underneath) before cutting around the perimeter of the object.
As often as we're reminded, everyone neglects one of the main workshop rules: Maintain your tools. This is crucial when it comes to CNC machines. If the CNC isnt calibrated or is out of square, the output wont match the input, no matter how long youve pored over the plans.
Once youve made sure that your machine is properly maintained, check your end mill or router bit the cutting piece that connects into the machine. It's very important to use an end mill that is specified for the particular material you are using, said Hood-Daniel. There are end mills specific for wood, plastic, aluminum, steel, and so on.
The shape of the bit matters as well. Down-cut bits tend to press the material downward as they are cutting, while up-cut bits pull the material up. Compression bits create a clean surface on both sides. Then you must consider the number of flutes, or the edges that wrap around the mill, which affect your feed rate and the edges finish. Make sure that you have the appropriate bit for your intended part. Hood-Daniel goes into a more in-depth discussion of end mill selection here.
In order to cut more accurate parts with clean edges, many CNC users will run their machine in many light, shallow passes, said Hood-Daniel. This process is very slow, and wears [down] the tip of the end mill.
Instead, program two separate roughing and finishing operations when youre in the CAM (Computer-Assisted Manufacturing) stage of assigning machining operations. The first pass will make a wide cut around the entire part, and then the second pass will shave the edges clean. Not only will your cuts be cleaner, your end mill will last longer.
Using the incorrect feed rate can have some interesting consequences, besides a broken mill and a creaky, inaccurate CNC. If you run your machine too slow, you risk burning the material or gumming up the cutting tool with melted material. In the case of milling aluminum, it can turn the end mill into a solid rod ... not very useful for cutting, Hood-Daniel said.
Generally speaking, plywood cuts best at a rate of 80 inches per minute (ipm) and a depth per pass of about 0.4 inches. Acrylic plexiglas works best at 130 ipm, with a depth per pass of 0.03 inches. Hood-Daniel urges the CNC user to keep in mind that these are general guidelines. Factors as disparate as the end mills sharpness and the materials temperature can affect how quickly and easily the material will be cut.
Another tip regarding cutting depth is to set the target depth to be slightly deeper than the true thickness of your material. For example, if cutting -inch plywood, set your target depth to around 0.8 inches, said Hood-Daniel. This ensures a full-depth cut.
Carelessly laid-out designs are the bane of both the environment and your dusty garage floor. Implement the principles of lossless design and lay each component as close to the other ones as possible. If you place parts edge edge to edge, the end mill only cuts through material once along the shared edge, said Hood-Daniel. That saves you time and money. It also lengthens the lifespan of your end mill.
If youre making multiples of one component, CAM software allows you to nest them automatically. Just make sure that your holding tabs are aligned with the tabs of neighboring parts so that they arent milled through when the other pieces are cut.
WIRED is where tomorrow is realized. It is the essential source of information and ideas that make sense of a world in constant transformation. The WIRED conversation illuminates how technology is changing every aspect of our livesfrom culture to business, science to design. The breakthroughs and innovations that we uncover lead to new ways of thinking, new connections, and new industries.
Kerf is defined as the width of material that is removed by a cutting process. It was originally used to describe how much wood was removed by a saw, because the teeth on a saw are bent to the side, so that they remove more material than the width of the saw blade itself, preventing the blade from getting stuck in the wood.
Over the years Ive heard some people use the term when referring to the angle on the edge of the part, but that would be an incorrect use of the word. The cut angle on the edge of the part makes measuring the kerf width sorta tricky, but for consistency, the word kerf should only be used when talking about the actual cut width.
When cutting parts on a CNC plasma or laser machine, you want to produce accurate cut parts, with final dimensions as close as possible to the programmed shape. So if you program a 6 by 6 square, and the plasma arc removes 0.200 of material, as it cuts, then the resulting part is going to be 5.8 by 5.8. So the actual tool path has to be compensated by 0.100 to the side of the programmed path, all the way around the part.
Rather than re-program the part at a different dimension, the CNC will take care of this automatically just by telling it which direction to offset, and by how much. Most modern CNCs take the actual kerf amount and automatically offset the tool path by 1/2 of that amount, so that the finished part comes out very close to the programmed dimensions. That is why the kerf value is often referred to as kerf offset.
Each cutting process removes a different amount of material, or kerf. The more precise processes, like waterjet and laser, remove a smaller amount of kerf, which is one of the reasons they can be more precise! A typical example shown here is for 1/2 thick mild steel.
Not only does kerf width vary from one process to the next, but there are lots of things that affect the kerf width for each process. Of course, as the thickness of material increases, it takes more power to cut through it. In the case of plasma, that means higher current and a larger nozzle. Laser increases power. Oxy-fuel cutting uses a larger nozzle with a wider cutting oxygen stream and hotter preheats. Waterjet uses either a larger nozzle/orifice combination, or a slower cutting speed. Regardless of the process, as the plate gets thicker, the kerf gets wider.
Kerf offset is traditionally adjusted by the machine operator at the CNC. Prior to running a program, the operator must enter the kerf width so that the CNC can calculate the actual tool path required to cut the part to the correct dimensions.
Modern thermal cutting and waterjet machine controls will also allow the kerf width value to be included in the part program, or to be called from a process database stored in the CNC. This makes it much easier for operators, since they dont need to look up the values for each material type and thickness they cut, but rather they simply select the material type and thickness, then the CNC looks up all of the process variables in the database.
End mills have cutting edges on their nose and sides that remove material from the surface of a piece of stock. They are used on computer numerical control (CNC) or manual milling machines to create parts with complex shapes and features such as slots, pockets, and grooves. Each end mill has flutes on its cutting head that carry the removed material away from the workpiece to prevent damage to the end mill or workpiece. Ball end mills create a round-bottomed groove in a workpiece. Square end mills cut a flat-bottomed groove with 90 inside corners. Corner-chamfer and corner-radius end mills make a flat-bottomed groove with chamfered or rounded inside corners. Chamfer mills are used to chamfer or bevel the edges of a workpiece. Corner-rounding end mills create a rounded outside edge on a workpiece. Drill mills have a nose with a pointed tip that can drill holes or create angled features in a workpiece.
Milling is the most common form of machining, a material removal process, which can create a variety of features on a part by cutting away the unwanted material. The milling process requires a milling machine, workpiece, fixture, and cutter. The workpiece is a piece of pre-shaped material that is secured to the fixture, which itself is attached to a platform inside the milling machine. The cutter is a cutting tool with sharp teeth that is also secured in the milling machine and rotates at high speeds. By feeding the workpiece into the rotating cutter, material is cut away from this workpiece in the form of small chips to create the desired shape. Milling is typically used to produce parts that are not axially symmetric and have many features, such as holes, slots, pockets, and even three dimensional surface contours. Parts that are fabricated completely through milling often include components that are used in limited quantities, perhaps for prototypes, such as custom designed fasteners or brackets. Another application of milling is the fabrication of tooling for other processes. For example, three-dimensional molds are typically milled. Milling is also commonly used as a secondary process to add or refine features on parts that were manufactured using a different process. Due to the high tolerances and surface finishes that milling can offer, it is ideal for adding precision features to a part whose basic shape has already been formed.
The time required to produce a given quantity of parts includes the initial setup time and the cycle time for each part. The setup time is composed of the time to setup the milling machine, plan the tool movements (whether performed manually or by machine), and install the fixture device into the milling machine. The cycle time can be divided into the following four times:
Following the milling process cycle, there is no post processing that is required. However, secondary processes may be used to improve the surface finish of the part if it is required. The scrap material, in the form of small material chips cut from the workpiece, is propelled away from the workpiece by the motion of the cutter and the spraying of lubricant. Therefore, no process cycle step is required to remove the scrap material, which can be collected and discarded after the production. Cutting parameters In milling, the speed and motion of the cutting tool is specified through several parameters. These parameters are selected for each operation based upon the workpiece material, tool material, tool size, and more.
During the process cycle, a variety of operations may be performed to the workpiece to yield the desired part shape. The following operations are each defined by the type of cutter used and the path of that cutter to remove material from the workpiece.
Milling machines can be found in a variety of sizes and designs, yet they still possess the same main components that enable the workpiece to be moved in three directions relative to the tool. These components include the following:
The above components of the milling machine can be oriented either vertically or horizontally, creating two very distinct forms of milling machine. A horizontal milling machine uses a cutter that is mounted on a horizontal shaft, called an arbor, above the workpiece. For this reason, horizontal milling is sometimes referred to as arbor milling. The arbor is supported on one side by an overarm, which is connected to the column, and on the other side by the spindle. The spindle is driven by a motor and therefore rotates the arbor. During milling, the cutter rotates along a horizontal axis and the side of the cutter removes material from the workpiece. A vertical milling machine, on the other hand, orients the cutter vertically. The cutter is secured inside a piece called a collet, which is then attached to the vertically oriented spindle. The spindle is located inside the milling head, which is attached to the column. The milling operations performed on a vertical milling machine remove material by using both the bottom and sides of the cutter. Milling machines can also be classified by the type of control that is used. A manual milling machine requires the operator to control the motion of the cutter during the milling operation. The operator adjusts the position of the cutter by using hand cranks that move the table, saddle, and knee. Milling machines are also able to be computer controlled, in which case they are referred to as a computer numerical control (CNC) milling machine. CNC milling machines move the workpiece and cutter based on commands that are preprogrammed and offer very high precision. The programs that are written are often called G-codes or NC-codes. Many CNC milling machines also contain another axis of motion besides the standard X-Y-Z motion. The angle of the spindle and cutter can be changed, allowing for even more complex shapes to be milled.
The tooling that is required for milling is a sharp cutter that will be rotated by the spindle. The cutter is a cylindrical tool with sharp teeth spaced around the exterior. The spaces between the teeth are called flutes and allow the material chips to move away from the workpiece. The teeth may be straight along the side of the cutter, but are more commonly arranged in a helix. The helix angle reduces the load on the teeth by distributing the forces. Also, the number of teeth on a cutter varies. A larger number of teeth will provide a better surface finish. The cutters that can be used for milling operations are highly diverse, thus allowing for the formation of a variety of features. While these cutters differ greatly in diameter, length, and by the shape of the cut they will form, they also differ based upon their orientation, whether they will be used horizontally or vertically. A cutter that will be used in a horizontal milling machine will have the teeth extend along the entire length of the tool. The interior of the tool will be hollow so that it can be mounted onto the arbor. With this basic form, there are still many different types of cutters that can be used in horizontal milling, including those listed below.
Another operation known as a straddle milling is also possible with a horizontal milling machine. This form of milling refers to the use of multiple cutters attached to the arbor and used simultaneously. Straddle milling can be used to form a complex feature with a single cut. For vertical milling machines, the cutters take a very different form. The cutter teeth cover only a portion of the tool, while the remaining length is a smooth surface, called the shank. The shank is the section of the cutter that is secured inside the collet, for attachment to the spindle. Also, many vertical cutters are designed to cut using both the sides and the bottom of the cutter. Listed below are several common vertical cutters.
All cutters that are used in milling can be found in a variety of materials, which will determine the cutter's properties and the workpiece materials for which it is best suited. These properties include the cutter's hardness, toughness, and resistance to wear. The most common cutter materials that are used include the following:
The material of the cutter is chosen based upon a number of factors, including the material of the workpiece, cost, and tool life. Tool life is an important characteristic that is considered when selecting a cutter, as it greatly affects the manufacturing costs. A short tool life will not only require additional tools to be purchased, but will also require time to change the tool each time it becomes too worn. The cutters listed above often have the teeth coated with a different material to provide additional wear resistance, thus extending the life of the tool. Tool wear can also be reduced by spraying a lubricant and/or coolant on the cutter and workpiece during milling. This fluid is used to reduce the temperature of the cutter, which can get quite hot during milling, and reduce the friction at the interface between the cutter and the workpiece, thus increasing the tool life. Also, by spraying a fluid during milling, higher feed rates can be used, the surface finish can be improved, and the material chips can be pushed away. Typical cutting fluids include mineral, synthetic, and water soluble oils.
In milling, the raw form of the material is a piece of stock from which the workpieces are cut. This stock is available in a variety of shapes such as flat sheets, solid bars (rectangular, cylindrical, hexagonal, etc.), hollow tubes (rectangular, cylindrical, etc.), and shaped beams (I-beams, L-beams, T-beams, etc.). Custom extrusions or existing parts such as castings or forgings are also sometimes used.
When selecting a material, several factors must be considered, including the cost, strength, resistance to wear, and machinability. The machinability of a material is difficult to quantify, but can be said to posses the following characteristics:
The material cost is determined by the quantity of material stock that is required and the unit price of that stock. The amount of stock is determined by the workpiece size, stock size, method of cutting the stock, and the production quantity. The unit price of the material stock is affected by the material and the workpiece shape. Also, any cost attributed to cutting the workpieces from the stock also contributes to the total material cost.
The production cost is a result of the total production time and the hourly rate. The production time includes the setup time, load time, cut time, idle time, and tool replacement time. Decreasing any of these time components will reduce cost. The setup time and load time are dependent upon the skill of the operator. The cut time, however, is dependent upon many factors that affect the cut length and feed rate. The cut length can be shortened by optimizing the number of operations that are required and reducing the feature size if possible. The feed rate is affected by the operation type, workpiece material, tool material, tool size, and various cutting parameters such as the axial depth of cut. Lastly, the tool replacement time is a direct result of the number of tool replacements which is discussed regarding the tooling cost.
The tooling cost for machining is determined by the total number of cutting tools required and the unit price for each tool. The quantity of tools depends upon the number of unique tools required by the various operations to be performed and the amount of wear that each of those tools experience. If the tool wear exceeds the lifetime of a tool, then a replacement tool must be purchased. The lifetime of a tool is dependant upon the tool material, cutting parameters such as cutting speed, and the total cut time. The unit price of a tool is affected by the tool type, size, and material.