The tungsten carbide bush also known as tungsten steel bushing, is a kind of component that protects the equipment, using the bushing, can effectively reduce the wear between the punch or bearing and the equipment and achieve a guiding role. The tungsten carbide bushing is mainly applied for stamping, with the features of wear resistance and impact resistance.

Excellent Characteristics Of Tungsten Carbide Bush

The tungsten carbide bushing has a series of excellent performances with high hardness, good concentricity, good perpendicularity, high wear resistance, high toughness, heat resistance and corrosion resistance. It has greatly improved the service life of the mold and has reduced the cost of molding manufacturers.

1. Advanced molding techniques can be adapted to produce a variety of shapes for carbide bush.

2. Small deformation with high accuracy.

3. High chemical stability.

4. High bending strength.

The Machining Method Of Tungsten Carbide Bush

The tungsten carbide bushing adopts CNC precision angles, inner hole grinder, precision surface grinding machine, precision internal and external round grinder, centerless grinder. The inner hole is grinded many times and polished into a mirror. The most suitable tool material for machining carbide bushing is a PCBN cutting tool.

The spray welding technology is adopted sometimes to increase the durability and service life of cemented carbide bush, which can reach HRC60 with better wear resistance. But the carbide bushing after welding needs turning machining to ensure the requirements for size and accuracy of the drawings.

Wide Applications Of Tungsten Carbide Bush

In the industrial fields, the application of cemented carbide bushing is very wide. The tungsten carbide sleeve is related to the role and purpose of its application environment in practical applications. In the valve application, the bushing should be mounted in the stem cover trap to reduce the valve leakage, for sealing. In the bearing application, the carbide bushing is adapted to reduce the wear between the bearing and the shaft seat, avoiding the clearance increasing between the shaft and the hole.

The tungsten carbide bushing is mainly used in the fields of stamping and stretching. The widely used tungsten carbide as tool material, includes a turning tool, a milling cutter, a planer, a drill bit, a boring cutter, etc, for cutting cast iron, non-ferrous metals, plastic, chemical fiber, graphite, glass, stone and ordinary steel, which can also be used for cutting materials which are difficult for machining, such as heat resistant steel, stainless steel, high manganese steel, tool steel.

In terms of stamping dies, the tungsten carbide bush is widely used because of high wear resistance, good finishing and no needing frequent replacement, thereby reaching the higher usage rate of equipment and personnel.

The carbide bushing has excellent chemical stability, which is widely applied in the industries of petrochemicals, submersible oil pumps, slurry pumps, water pumps, centrifugal pumps. With the increase in oil production, the shallow surface of the oil is reduced, In order to ensure oil usage, people have gradually developed to extract from the large deep well, but the difficulty of mining gradually increases and the mining components have high requirements for wear resistance, corrosion resistance or impact resistance. The tungsten carbide bush used as the wear-resistant component in the oil machinery, has high hardness, excellent wear resistance and a high degree of surface finishing, satisfying the use requirements for a daily and special performance in the oil machinery industry.

High performance tungsten carbide bush is a type of protective component with wide industrial applications, with high hardness, superior wear resistance, high strength, high toughness, heat resistance and corrosion resistance.

JTR has more than decades of experience in CNC manufacturing services in China and can offer one-stop service (CNC machining parts & CNC machining prototype) for our OEM customers. All processes are carried out through hundreds of advanced CNC Machining machines, lathes, and other manufacturing facilities, ranging from blasters to Ultra Sonic washing machines. JTR CNC Machining Center not only has advanced equipment but also have a professional team of experienced engineers, operators and inspectors to make the customer’s design come true.

Precision CNC machining services for the automotive, heavy truck, HVAC and mining industries. Works with gray iron, steel and aluminum castings as well as steel forgings and steel bar stock. Capable of horizontal machining parts of 25 x 36 in. and vertical machining

JTR offers the following CNC Machining services for our customers:

● Prototype Machining & custom machined parts

● Plastic 3D Printing & Metal 3D Printing

● Precision CNC Machining & Tooling & mold make Services

● Sheet Metal Prototyping & Sheet Metal Fabrication Service

How Do You Compare Up Milling And Down Milling For CNC Machining

Up milling and down milling are two common CNC Milling  methods in CNC machining. Many people don’t understand the difference between them. Today’s article will talk about the difference between up milling and down milling.

The cutting edge of the milling cutter will be subjected to impact load every time it cuts in. In order to successfully milling, we must consider the correct contact mode between the cutting edge and the material when the cutting edge cuts in and cuts off in a cutting. In the milling process, the workpiece is fed in the same or opposite direction along the rotation direction of the milling cutter, which will affect the cutting in, cutting and whether to use up milling or down milling.

Up Milling Vs Down Milling For CNC Machining

The Golden Rule Of Milling – From Thick To Thin

When milling, the formation of cutting must be considered. The decisive factor of cutting formation is the position of the milling cutter. It is required to form thick chips when the cutting edge cuts in and thin chips when the cutting edge cuts out, so as to ensure a stable milling process. Be sure to remember the golden rule of milling “from thick to thin” to ensure that the chip thickness is as small as possible when the blade is cut out.

Up Milling

In up milling, the cutting tool feeds in the direction of rotation. As long as the machine tool, fixture and workpiece allow, up milling is always the preferred method. In edge up milling, the chip thickness will gradually decrease from the beginning of cutting and finally reach zero at the end of cutting. In this way, the cutting edge can avoid scratching and rubbing the part surface before participating in cutting.

Large chip thickness is advantageous, and the cutting force tends to pull the workpiece into the milling cutter to keep the cutting edge cutting. However, because the milling cutter is easy to be pulled into the workpiece, the CNC machine tool needs to eliminate the backlash to deal with the feed gap of the worktable. If the milling cutter is pulled into the workpiece, the feed will increase unexpectedly, which may lead to excessive chip thickness and fracture of the cutting edge. Back milling should be considered at this time.

Down Milling

In down milling, the feed direction of the cutting tool is opposite to its rotation direction. The chip thickness increases gradually until the end of cutting. The cutting edge must be forcibly cut in, resulting in scratching or polishing due to friction, high temperature and frequent contact with the work hardened surface caused by the front cutting edge. Will shorten the life of CNC tools.

The thick chips and high temperature produced by the cutting edge will lead to high tensile stress, shorten the tool life, and the cutting edge will usually be damaged quickly. It may also cause chips to stick or weld to the cutting edge, which will then carry them to the starting position of the next cutting, or cause the cutting edge to collapse instantaneously.

The cutting force tends to push the milling cutter and the workpiece away from each other, while the radial force tends to lift the workpiece from the workbench. When the machining allowance changes greatly, down milling is better. down milling is also used when machining superalloys with ceramic blades, because ceramics are sensitive to the impact when cutting into the workpiece.

Feed Direction Of Workpiece Fixture Tool

Different requirements are put up for workpiece fixture. It should be able to resist the lifting force during the down milling process. It should be able to resist downforce during down milling.

Comparison Between Up Milling And Down Milling

Up milling and down milling are two common CNC Milling  methods in CNC machining. Many people don’t understand the difference between them. Today’s article will talk about the difference between up milling and down milling.

The cutting edge of the milling cutter will be subjected to impact load every time it cuts in. In order to successfully milling, we must consider the correct contact mode between the cutting edge and the material when the cutting edge cuts in and cuts off in a cutting. In the milling process, the workpiece is fed in the same or opposite direction along the rotation direction of the milling cutter, which will affect the cutting in, cutting and whether to use up milling or down milling.

Up Milling Vs Down Milling For CNC Machining

The Golden Rule Of Milling – From Thick To Thin

When milling, the formation of cutting must be considered. The decisive factor of cutting formation is the position of the milling cutter. It is required to form thick chips when the cutting edge cuts in and thin chips when the cutting edge cuts out, so as to ensure a stable milling process. Be sure to remember the golden rule of milling “from thick to thin” to ensure that the chip thickness is as small as possible when the blade is cut out.

Up Milling

In up milling, the cutting tool feeds in the direction of rotation. As long as the machine tool, fixture and workpiece allow, up milling is always the preferred method. In edge up milling, the chip thickness will gradually decrease from the beginning of cutting and finally reach zero at the end of cutting. In this way, the cutting edge can avoid scratching and rubbing the part surface before participating in cutting.

Large chip thickness is advantageous, and the cutting force tends to pull the workpiece into the milling cutter to keep the cutting edge cutting. However, because the milling cutter is easy to be pulled into the workpiece, the CNC machine tool needs to eliminate the backlash to deal with the feed gap of the worktable. If the milling cutter is pulled into the workpiece, the feed will increase unexpectedly, which may lead to excessive chip thickness and fracture of the cutting edge. Back milling should be considered at this time.

Down Milling

In down milling, the feed direction of the cutting tool is opposite to its rotation direction. The chip thickness increases gradually until the end of cutting. The cutting edge must be forcibly cut in, resulting in scratching or polishing due to friction, high temperature and frequent contact with the work hardened surface caused by the front cutting edge. Will shorten the life of CNC tools.

The thick chips and high temperature produced by the cutting edge will lead to high tensile stress, shorten the tool life, and the cutting edge will usually be damaged quickly. It may also cause chips to stick or weld to the cutting edge, which will then carry them to the starting position of the next cutting, or cause the cutting edge to collapse instantaneously.

The cutting force tends to push the milling cutter and the workpiece away from each other, while the radial force tends to lift the workpiece from the workbench. When the machining allowance changes greatly, down milling is better. down milling is also used when machining superalloys with ceramic blades, because ceramics are sensitive to the impact when cutting into the workpiece.

Feed Direction Of Workpiece Fixture Tool

Different requirements are put up for workpiece fixture. It should be able to resist the lifting force during the down milling process. It should be able to resist downforce during down milling.

Comparison Between Up Milling And Down Milling

Aluminum is a vital material for a broad range of industries, and some of the alloys from the aluminum family are perfect for aerospace applications. When talking about aircraft components, which aluminum alloy are they made out of? In this article, we are going to focus on some advanced aluminum alloys used in aerospace industries and why they are used.

What Types of Aluminum Alloys Used in Aerospace Applications – Aerospace Grade Aluminum

As early as the 19th century, aluminum was used in aerospace. Count Ferdinand von Zeppelin made his hydrogen-filled airship from aluminum. The Wright brothers used an aluminum engine cylinder in their first manned flight in 1903. They found that metals can be strengthened by heating. Many metals, including iron and aluminum, will form atoms if heated and cooled rapidly, a more orderly crystalline structure, which makes them very corrosion-resistant. Aluminum is still the most used metal in modern aerospace applications because of its high strength, low density, and corrosion resistance.

Aluminum in the aerospace industry is almost always used with other metals to form alloys. Sometimes a small part of the added metal will significantly change the properties of the alloy. Most metals begin to decompose when exposed to oxygen. When exposed to oxygen, the combination of heat and oxygen is almost always destructive, aluminum will form a layer of aluminum oxide, namely Al2O3, which exists in the mineral corundum in crystalline form. Corundum is transparent, but natural impurities such as iron, titanium, chromium, vanadium, and magnesium will turn these crystals into red, blue, green, or other colors. We call them ruby, sapphire, and emerald. The top layer of this transparent alumina is formed on aluminum alloy, making it very corrosion-resistant. In fact, The aerospace industry is very pleased to find this transparent aluminum. Nitrogen alumina is formed by fusing aluminum oxide and nitrogen under pressure with a laser to remove electrons and chemically bond. The resultant material is transparent metal, which makes the window and telescope shield used in space excellent because it is stronger and lighter than glass or any other plastic-based alternative. Aluminum alloys used in aerospace over the last 70 years include the alloys 2014, 2219, 7050, and 7055. Aerospace CNC machining at JTR offers high-standard parts with a variety of dimensions and specifications.

– 2014 Aluminum Alloy: an aluminum-based alloy often used in the aerospace industry. 2014 is the second popular alloy of the 2000-series, only after Al 2024. Typical applications of aluminum 2014 are heavy-duty forgings, plates, and extrusions for aerospace fittings, wheels, tanks, and major structural components.

– 2219 Aluminum Alloy: 2219 is an alloy in the wrought aluminum-copper family, it has high strength, but is generally less corrosion resistant than other types of aluminum alloys. The excellent structural strength, high fracture toughness and resistance to stress corrosion cracking make it be widely used in supersonic aircraft skin and structural members. The space shuttle external tanks are also made from aluminum 2195, which replaced the 2219 aluminum-copper alloy. The newer alloy 2050 may be even better than 2195 currently used by space with improved tensile strength and fracture toughness.

– 7050 Aluminum Alloy: 7050 is known as a commercial aerospace alloy, with high toughness, high strength, and high-stress corrosion resistance. When it comes to the aerospace uses of aluminum 7075, you can find it is often used to make fuselage frames, bulkheads, and various other aircraft parts. Al 7075 is available in T7451 and T7651 tempers.

– 7055 Aluminum Alloy: 7055 is heat treatable wrought aluminum alloy that is usually applied for use in the aerospace sector and other high strength requirement areas. It provides high ultimate tensile strength. 7055-T77511 is specially developed for compression-dominated structures.

Other aerospace-grade aluminum alloys including 2024 (2024-T3, 2024-T4/T351, 2024-T851), 6061, 5052, etc.

One of the greatest challenges in CNC machining is the complexity and precision of the parts to be produced. Let’s learn how to improve CNC machining’s efficiency.

Parts for automotive, defense, aerospace or medical industries may require advanced CNC machines, where various spindles are selectable, capable of maneuvering, cutting, boring and shaping parts controlled through multiple axis. Examples of these machines include 3 to 5-Axis Machining Centers and 2 to 8-Axis Turning Centers. They allow one, two or even Multi-Spindle (mass production) designs.

From standard to highly complex jobs or for batch production, you may consider either Horizontal or Vertical CNC Lathes with 2 to 5-Axis or Milling Machines with 3 to 5-Axis.

Hwacheon has a range of Horizontal Turning Centers to select from :

CUTEX Range with Linear Guide Way System, suitable for a range of applications and production needs. Available in 2 to 5-Axis.

Hi-TECH Line with Solid Hand Scrapped Box Guide Ways, most capable to handle toughest materials at highest precision.

Multi-Axis Turning Centers are the right choice if complex parts and the need to complete the part in one setting.

Vertical Turning Machines like Hwacheon’s VT Range are most effective to machine parts where the part diameter is much bigger than the part length. Eg. gear wheels, drums, disk, pump housing, engine housing and rings and many more.

For production in “High Mix – Low Volume” mode with quick turnarounds of various parts and required machine settings, Hwacheon’s new 5-Axis Machining Center D2-5AX offers an incredible solution with its ø600mm 2-axis table, 4+1 to full 5-axis and 4 selectable spindles (option).

For Mold & Die applications, Hwacheon offers the proven M2-5AX as well as the new M3-5AX 5-Axis Machining Center. Highest precision, accuracy and surface finish are guaranteed by this gantry designed machines.

For the toughest materials like titanium, Inconel or heat resistant stainless steel, the new M4-5AX with a maximum spindle torque of up-to 1009Nm, ensures highest stability and efficiency during simultaneous cutting in 5-axis.

Turning Centers like Hwacheon’s T2 with up-to 8 axis or the new C1 / C2 with integrated tool changer provides the ideal platform for “High Mix – Low Volume” production needs.

One of the greatest challenges in CNC machining is the complexity and precision of the parts to be produced. Let’s know what are the requirhttps://www.jtrmachine.com/articles/detail/3-requirements-for-the-division-of-cnc-machining-processes.htmlements of CNC machining.

Parts for automotive, defense, aerospace or medical industries may require advanced CNC machines, where various spindles are selectable, capable of maneuvering, cutting, boring and shaping parts controlled through multiple axis. Examples of these machines include 3 to 5-Axis Machining Centers and 2 to 8-Axis Turning Centers. They allow one, two or even Multi-Spindle (mass production) designs.

From standard to highly complex jobs or for batch production, you may consider either Horizontal or Vertical CNC Lathes with 2 to 5-Axis or Milling Machines with 3 to 5-Axis.

Hwacheon has a range of Horizontal Turning Centers to select from :

CUTEX Range with Linear Guide Way System, suitable for a range of applications and production needs. Available in 2 to 5-Axis.

Hi-TECH Line with Solid Hand Scrapped Box Guide Ways, most capable to handle toughest materials at highest precision.

Multi-Axis Turning Centers are the right choice if complex parts and the need to complete the part in one setting.

Vertical Turning Machines like Hwacheon’s VT Range are most effective to machine parts where the part diameter is much bigger than the part length. Eg. gear wheels, drums, disk, pump housing, engine housing and rings and many more.

For production in “High Mix – Low Volume” mode with quick turnarounds of various parts and required machine settings, Hwacheon’s new 5-Axis Machining Center D2-5AX offers an incredible solution with its ø600mm 2-axis table, 4+1 to full 5-axis and 4 selectable spindles (option).

For Mold & Die applications, Hwacheon offers the proven M2-5AX as well as the new M3-5AX 5-Axis Machining Center. Highest precision, accuracy and surface finish are guaranteed by this gantry designed machines.

For the toughest materials like titanium, Inconel or heat resistant stainless steel, the new M4-5AX with a maximum spindle torque of up-to 1009Nm, ensures highest stability and efficiency during simultaneous cutting in 5-axis.

Turning Centers like Hwacheon’s T2 with up-to 8 axis or the new C1 / C2 with integrated tool changer provides the ideal platform for “High Mix – Low Volume” production needs.

What are CNC working principles?

How CNC machines work?

In CNC system a dedicated computer is used to perform all the essential functions as per the executive program stored in the computer memory. The system directs commands to servo drives to drive the servo motor & other output devices like relays, solenoids, etc. to initiate the operations such as motor starting & stopping, coolant on & off, tool changing, pallet changing, etc. and other miscellaneous functions.

Once the system gives, it becomes necessary to ensure that the particular function has been completed. This is done by “Feed Back Devices.” Continuous feedback device like linear scale, encoder, resolver, etc. are used as position feedback of the motor. Some sensors like proximity switch, limit switch, pressure switch, flow switch, and float switch, etc. are used as feedback devices to monitor the different operations. Thus all operations of the CNC machine are monitored continuously with appropriate feedback devices. So that CNC system is called as “Closed Loop” system. In case of failure in any failure feedback, the system generates a “Fault Message.”

The principles of CNC operation.

Movement of X, Y, Z axis are controlled by a motor which supplies either Alternating current or Direct current.

Movement of the machine is done by giving commands.

All the operations are carried out by codes like speed, feed, depth of cut, etc.

For each operation separate code is available.

The warning system is available to save guard the various operations and components.

Types of CNC Controllers.

The main determining factor of CNC machine tools is the accuracy of programming. Programming needs to be done by the system. In the machining industry, the most commonly used systems for CNC machine tools are these: Japan FANUC CNC system, Germany Siemens CNC system, Japan Mitsubishi CNC system, Germany HEIDENHAIN CNC system and so on.

In CNC, the CNC threads is the mainly tool to do work. There are two basic types of machined threads: internal threads and external threads.

Internal Threads

Internal threads are machined using a single-lip threading tool—not a traditional threading tap. On parts with internal hole features in need of threading, the actual threads need to be removed from your CAD model, leaving only the pilot diameter. Our software recognises a hole for threading if:

it falls within the diameter range for the desired thread and,

is in one of the three cardinal axes for milling or,

is perpendicular to the axis of revolution for turning

Protolabs supports right-hand threaded holes on machined parts for UNC and UNF threads ranging from a #2 and up to a ½ in.; metric threads are also available ranging from M2 to M12. Location and method of manufacturing may limit some threads from becoming eligible.

Another key factor to keep in mind is our maximum depths for threads based on our threading tools. Our #2 threads have a maximum thread depth from the top of surrounding features of 5.1mm and our ½ in. threads can go much deeper—up to 25.4mm of threading depth is available. For metric threads, capabilities range from 5.1mm and 25.4mm in depth. Threads depths will gradually increase as the diameter of the threads increase. More on that later in the design tip.

Internal threads are also available on turned parts. Many of the same rules apply for machining threads using live tooling on a lathe, but the available threads are more limited than milling. UNC and UNF threads range from #4-40 to ½-20 and metric threads from M3 to M10. With the addition of live tooling, we are able to produce threaded features radially, axially, and on-axis. This impacts the threading as some threads are available on-axis only. Please pay close attention to your quote or contact a customer service engineer for further clarification. A complete chart of turned threaded holes are available at protolabs.co.uk, and be sure to select turned parts under standard holes to view the availability of these options.

In machining internal threaded holes, a hole may often times be longer than what our threading tools are able to reach. In this case, you have a few options depending on your needs.

With a long through hole that exceeds the maximum reach, select the hole from the side that you anticipate the screw to be started from as shown in image 1. If your screw is required to pass the entire way through the part, you would also have to pass a tap through the hole (in a secondary process) to complete it.

You can also select both sides of the feature to be threaded as shown in image 2, but notice the maximum thread depths as they overlap with each other in the hole. This raises concern with threading the features from both sides, because you risk the threads being cross threaded and a screw may not pass all the way through the part cleanly. But as long as the threads don’t intersect as seen in image 3, selecting threads from both sides is typically fine.

External Threads

The introduction of lathe has improved our external threading capabilities, and you can now get external threads for select sizes as long as your parts qualify for turning. We still use a custom threading tool with a selected number of thread sizes, depths, and placements within the part geometry. However, Protolabs’ advanced turning process offers external threads on the centreline of the part, as well as live tooling that allows for internal holes to be threaded, as long as they follow similar guidelines as milling. And it’s not limited to on-axis holes—axial and radial holes are also available.

Just like internal threads, external thread design for turned parts need to have the thread removed from the CAD model in order for our software to recognise it. Additionally, please model your external threads for milling; don’t model them for turning. After you receive your quote for turning, you will then have the ability to select the appropriate thread size.

External milled threads are designed into parts much less frequently than internal threads, but nonetheless, can still be machined effectively. External milled threads are produced on the half diameter, and then the part is rotated 180 degrees where the opposing threads are machined in the same way. If you have larger, coarse external threads this does work well—we’re able to produce quality ½ in. threads, but you may still want to chase the threads to remove any remaining material or mismatch as the threads are produced in two different machining set-ups.

Smaller external threads such as a #6-32 are much more difficult to produce with a ball or flat end mill as a larger radii would be left in the root of the thread since the pitch is too tight. You would be required to chase the threads with a thread cutting die in order to remove the remaining material. On many parts, a 0.2mm to 0.4mm radius would be left.

Coil Inserts

Coil inserts are also available if you require stronger threads. Coil insert threads are applied to the holes, but the coil inserts are not installed during manufacturing. The inserts would need to be installed by the user after the part is manufactured, but before the part can be assembled. Coil Inserts are available in UNC and UNF threads ranging from a #2 to ½ in., and metric from M2 to M12 with the same depths as standard threaded holes. Protolabs is optimised for HeliCoil brand inserts and we recognise standard sizes and lengths.

From left to right, image 1, 2, and 3 depict three methods of approaching maximum thread depths.Click to enlarge

External threads, turned on a lathe

The CAD model illustrates an as-milled view of an external thread with resulting radii highlighted in yellow. This would be for milled parts only.Click to enlarge

CNC Milling is the process of cutting and drilling material (like wood or metal). A milling machine, regardless of whether it’s operated manually or through CNC, uses a rotating cylindrical tool called a milling cutter. It is held in a spindle and can vary in form and size.

The main difference between a milling machine and any other drilling machine is the ability to cut in different angles and move along different axes.

CNC milling’s application

The applications for CNC machining have grown extensively over the years. Today, there are numerous industries that rely to some extent on CNC milling and contract machining services. Here are just a few of the industries where CNC machining is a feature of the operation:

Automotive – Car manufacturers depend on CNC contract machine work for the custom parts they need to produce vehicles.

Metal Fabrication – CNC milling machines are a central part of companies that prepare metal for later manufacturing purposes.

Mining – CNC lathes make the metal extraction process more precise and efficient.

Packaging – CNC machines make precise grooves in packaging to allow for improved grip for better package protection.

Aerospace – Aerospace companies use CNC centers to prototype and produce a wide variety of parts.

Oil and Gas – Oil and gas companies need durable, high-performance parts, and CNC technology makes it easy to acquire them.