About BT Tool Holders: BT30, BT40, BT50

There are two types of tools in CNC machinery: tool holders and cutting tools. There are other items related to tool holders, such as collets, set screws, wrenches and other setup tools.

 

Tools for CNC machinery are manufactured by a variety of brands and come in few different standards.

 

BT standard for tool holders originated in Japan and is somehow similar to CAT tool holders.

 

As well as CAT tool holders, it has numerical designations that correspond to the size of the taper: BT-30, BT-35, BT-40, BT-45, and BT-50. The higher the number is, the bigger is the taper.

 

Like CAT Tooling, BT Tooling comes in a range of sizes designated as BT 30, BT 40, BT 50, etc. and uses the same NMTB body taper as CAT 40. BT tooling is symmetrical about the spindle axis, which CAT tooling is not. This gives BT tooling greater stability and balance at high speeds.

 

BT Tool Holders will accept both Imperial and metric sized tools. BT Tooling looks very similar and can easily be confused with CAT tooling.

 

The difference between CAT and BT is the flange style, thickness, and the thread for the pull stud is a different size. BT Tool Holders use Metric thread pull studs (retention knobs).

 

If to compare BT to CAT tool holders – they look very similar and can be easily confused, however, they has different flange system and its thickness is different too. Also, the retention knobs are different. Therefore BT and CAT tool holders are not interchangeable.

 

Though both standards use the same NMTB body taper. BT tool holders are symmetrical around the main spinning axis, while CAT tool holders are not. That makes BT tool holders better balanced and more stable at higher speeds.

 

BT tool holders along with CAT and HSK standards are among the most used in CNC machinery. They will accept both imperial and metric sized tools; however, BT tools come in metric sizes. They are durable and are best choice for very high speed machinery.

 

BT Tools: Overall Maintenance

To insure proper performance of your toolholders, overall cleanliness of toolholder, collet pocket, collet, and nut must be maintained. It’s important to remember that all these components are manufactured to perform within tolerances of ten-thousandths (.0001”) of an inch.

 

Any dirt, dust, oil, chips, or other contaminant left on the spindle, taper, flange, collet, collet pocket, or nut can cause poor T.I.R. (runout) leading to premature wear of cutting tool, toolholder, and spindle mouth.

 

We recommend a regular preventive maintenance program be implemented in your shop to protect your investment in cutting tools, toolholders, and collets, and reduce scrap.

 

BT Tools and Performance & Productivity

BT tools allow use of ATC (Automatic Tool Change) technology to maximize the speed and productivity of manufacturing.

 

BT tool holders perform work with high strains and pressures, so be sure to store them safely without any chance for the tool being damaged – as this may cause some misbalance that can be critical at high speeds and precise CNC machinery.

 

BT Tool Holders: Bottom Line

Depending on your particular machining tool needs, the wide array of BT Holders that are manufactured and sold can help your job to me more efficient.

 

If you need more information of BT tool holder or CAT tool holder, I recommend you to visit Shin-Yain Industrial Co., Ltd. – they are the professional manufacturer of tool holders. To get more details of these products, please do not hesitate to contact with SYIC.

 

 

Article Source: https://toolholderexchange.com/bt-tool-holders-bt30-bt40-bt50/

Basic Information of Tool Holders and Static Tool Holders

Tool holders (toolholders) are the physical interface between tooling and the machine tool. They come in a multiple of different machine mount styles from the older R8 style to newer HSK or VDI mount.

 

Tool holders have three main parts: the taper, the flange, and the collet pocket. Driven or “live” tooling is powered, while static tool holder is not.

 

  • The taper is the conically-shaped area of the tool holder that enters the spindle during tool changing.
  • The flange is the part of the tool holder to which the automatic tool changer is attached when the tool holder is moved from the tool changer to the spindle.
  • The collet pocket is the area into which the collet is inserted before being secured by various types of collet nuts.

 

Some tool holders shrink-fit around the machine tool or cutting tool and remain firmly in place. Others are optimized to the smallest size possible to allow for maximum clearances during machining.

 

Tool Holder Types

Industrial buyers can find these types of tool holders at some manufacturers:

 

  • Machine arbors are motor-driven shafts that turn machine tools.
  • Blank adapters can be customized for specific applications or machining tasks.
  • Boring heads can hold a variety of cutting tools, but are used mainly with boring bars.
  • Collet chucks use collets of various sizes to hold machine tools.
  • End mill holders are designed to holdend mills during milling operations.
  • Milling or drilling chucks are used to hold various cutting tools during milling or drilling applications.
  • Outer diameter (OD) and inner diameter (ID) tool holders can hold a variety of cutting tools.
  • Shell or face mill adaptors are designed to hold shell or face mills, tools used to cut surfaces.
  • Side cutter holders are designed to hold side cutter tools.
  • Saw blade holders are designed to hold saw blades.
  • Tapping chucks are designed to hold tapping tools for threading operations.

 

Mounting Styles

When selecting tool holders, buyers need to specify a mounting style.

 

  • R8 is used by a majority of Bridgeport machines manufactured after 1965; however, this taper is seldom used with today’s high speed machining (HSM) equipment.

 

  • Morse taper (MT) is available in four common sizes: #1, #2, #3, and #4. Each size has a tapered fit for fast changes.

 

  • National Machine Tool Builders (NMTB) defined the NMTB taper for all CNC milling machines. The standard is 3.5 in. per ft. and can require a drawbar.

 

  • Caterpillar®developed the CAT® mounting style, sometimes called the V-flange, to standardize the tooling for its machines. Designations such as CAT-40, CAT-50 and CAT-60 refer to the NMTB taper size. (Caterpillar and CAT are registered trademarks of Caterpillar, Inc.)

 

  • BT is similar to CAT, but is balanced and symmetrical around the axis of rotation. BT uses the same NMTB body-taper measurement notations but uses a metric pull-stud thread.

 

  • Hollow shank tooling (HSK) is designed to increase grip as spindle speed increases. It does not have a pull stud and is often used with HSM. VDI is designed for quick-change tooling and is available in both dovetail and straight-shank versions.

 

  • Tool holders that use base mount tooling (BMT) and straight shank tooling are also available.

 

Tool Holder Sizes

The projection length of the tool holder is the distance from the gage line (the reference mounting surface) to the end of the tool holder. If specifying a collet pocket is applicable, buyers can choose an ER or TG type.

 

Features and Applications

Tool holders can be coolant-fed or have a coolant-thru flange. Some are optimized to the smallest size possible to allow for maximum clearances during machining. Each tool holder is designed for a specific application and tailored to optimize both machine performance and operational efficiency.

 

Tool Holder Manufacturer

Where to find the excellent tool holder manufacturer? I will say Shin-Yain Industrial Co., Ltd. is the recommendable static tool holder manufacturer. The company is specializing in numerous tool holders, like collet holder, static tool holder, CAT tool holder, BT tool holder etc. all can be found. If you have any interest, try to check out SYIC’s website and send inquiry to them.

 

 

Article Source: Tool Holders Information | Engineering360

The Differences between CAT, BT and HSK Tool Holder

BT & CAT tool holder – often referred to as “V-flange” by tooling manufacturers and machinists alike- is the most accepted and widely used standard of conventional milling tooling in the U.S. today. The “CAT” designation was developed by industrial conglomerate Caterpillar Inc. in order to standardize their machinery and has become the U.S. national standard. The “BT” series, on the other hand, is the Japanese equivalent and is more prevalent internationally, particularly in Europe since it was developed there. CAT and BT series holders are similar in that they both have the same 7:24 taper ratio and require the use of a retention knob, or pull stud, to secure the holder within the machine spindle (CAT tool holders generally have a standard thread while BT’s are mostly metric).

 

The difference between the two styles lies in the flange design where the BT bottom flange is thicker and engaged differently by the tool changer. Typical variations are CAT40, CAT50, BT30, and BT40 where the numerical portion signifies the taper dimension (the larger the number, the larger the holder). Because they are so similar, many CNC machine manufacturers and industrial tool suppliers offer the choice between CAT and BT spindles and there is some debate as to the efficacy of doing so. So why choose one over the other? Ease of tooling procurement. CAT tool holders are widely distributed in the U.S. while BT holders can be more easily procured internationally. But functionally speaking, there is little difference between the two.

 

There are some important limitations to note, however, when using CAT and BT systems. Both engage the CNC machine with a single-contact surface with a small gap existing between the flange of the tool holder and the spindle face. As a result, there can be inaccuracies that result from higher speeds that exceed 800 RPM’s, as centrifugal forces pull the holder up toward the spindle. While balanced holders help alleviate this problem, newer CNC clamping systems without this imitation- such as HSK- are rapidly gaining traction.

 

HSK is a German standard- translating to “Hollow Shank Taper” in English- that bears no resemblance to the CAT and BT styles mentioned above. The taper is much shorter and engages the spindle in a different fashion (i.e. no retention knob) with a cleverly designed dual contact method. The HSK system contains an internal clamping mechanism providing both radial and axial connection (thus the “dual contact”) providing a tremendous rigidity lacking in most CAT/BT set-ups. This allows for improved repeatability leading to increased tool life in high speed machining applications- the Holy Grail for production manufacturers.

 

Within the HSK family, there are 6 main styles (designated by letters “A-F” for differing applications) with HSK-63A being the most widely used today. While this style is becoming more popular, it does have some limitations. Due to the newer technology, HSK machine and tooling costs remain expensive and thus is not as popular among smaller manufacturers. However, for those engaged in machining high-value and precision parts, the HSK technology can offer tremendous value.

 

If you are interested and need more information about HSK, BT, and CAT Tool Holder, welcomes to visit the website of Shin-Yain – various tool holder series can be found on our website. Feel free to contact us!

 

Article Source: http://blog.allindustrial.com/the-differences-between-cat-bt-and-hsk-tooling/