How much do you know about hole machining?

In machining, hole machining accounts for about 1/3 of the total machining. Hole machining is semi-enclosed cutting. Chip removal, heat transfer, cutting liquid cooling are all difficult, especially more difficult hole deep processing.

The classification of the hole:

1) by shape: there are cylindrical holes, conical holes, drum holes, polygonal holes, spline holes and other special-shaped holes (such as curved holes), etc. Among them, cylindrical holes are most widely used.
2) by form: there are through-hole and blind hole (blocked hole); Deep hole (L/D = 5 ~ 20 is a general deep hole, L/D is a medium deep hole, L/D is a medium deep hole, and L/D﹥30 ~ 100 is called a special deep hole) and a shallow hole.
3) according to the size of aperture: there are big holes (D﹥100mm), ordinary holes (D = 10～100mm), small holes (D＝1～10mm) and micro holes (D ＜ 1mm).
4) according to the processing mechanism: mechanical processing, special processing, electromechanical compound machining, etc. Although there are many special machining methods, the traditional machining will still be the main method of hole machining because of the expensive equipment and low processing efficiency.
5) according to the machining accuracy: Rough machining holes (such as holes after boring and rough boring), semi-fine bore (such as reaming, coarse ream, semi-fine boring hole) and precise hole (such as fine hinge, fine pull, fine grinding, honing, grinding hole). Precision holes generally refer to tolerances above grade IT7 – IT6 and surface roughness is Ra﹤ 0.8～0.4m. Its geometrical shape precision (such as roundness, cylindrical degree, axis straightness, etc.) is generally specified in the range of 1/2 ~ 1/3 of its dimensional tolerance band.

With the rapid development of aerospace, automobile, high-speed train, wind power, electronics, household appliances, energy, mold, hydraulic, machine tool and precision machinery and other equipment manufacturing industries and the upgrading of products, the application of precision holes is increasing day by day.

Characteristics of hole machining:

Hole machining is a complex process, which must solve the problem of chip removal, cooling, lubrication and guidance. Hole machining has a wide range of applications. The quality of its processing will directly affect the use and life of the product. The cutting mechanism of hole machining is complex, the cutting tools are various, and the machining is difficult. In mechanical parts, the precision and surface roughness of the hole are required to be improved day by day. Precision hole machining is often the key to production. In order to improve the economic efficiency of hole processing, many factories use advanced cutting tools: polygonal rotary broaching tools, single blade boring reamer of cemented carbide, precision diamond burnishing tools or cubic boron nitride reamer, roller burnishing tools and other new processes.

roller burnishing tools, skiving burnishing tools, rotary broaching tools, deburring and chamfering tools, external roller burnishing machines manufacturer

RBT is the one-stop solution provider for burnishing hole. Our burnishing tools covers roller burnishing tools, skiving burnishing tools, rotary broaching tools, deburring and chamfering tools, external roller burnishing machines, etc. Since the company was founded in 2007, we have served over 2,000 customers worldwide. Welcome new and old customers come to the consultation to discuss!

The latest machining technic of polygonal holes and rotary broaching tools you should know

It is well known that the traditional machining methods of polygonal holes include punching and spark erosion fabrication, etc. All of these methods needs special purpose machine to finish the machining hole, meanwhile spark erosion fabrication method will produce waste gas to pollution the environment, and relatively expensive. With the innovative technology in machinery field, and improvement of machining technic, RBT company has developed a complex tool, which is named ‘Polygonal Rotary Broaching Tool’. This tool does not need a special purpose machine, only needs driving in any power unit for working; it has the advantages of economy and environmental protection. Just single set-up, and the serial procedure is completed once, for machining different shaped hole, just only need to replace the broaching head; therefore, the accuracy and efficiency are greatly improved. This tool is suitable for processing metal parts with hardness less than HRC30.

Hexagonal Rotary Broaching Tool, RBT Rotary Broacher, Rotary Broaching Head, Hexagonal Rotary Broaching Tool Manufacturer, Hexagonal Rotary Broaching Tool Supplier, Cheap Rotary Broaching Tool, Rotary Broacher Factory Price, Allen Wrench Broaching Tool

For different requirements of hole shape, the hole shapes are available: hexagonal holes, square holes, stellated holes, splined holes, column-shaped holes, etc.

Video of Hexagonal Rotary Broaching Tool

Catalogue & Operating Manual of Hexagonal Rotary Broaching Tool

Usages & Notes

Keep and use the tool is clamped onto the rotatable and feeding machine turret (holder), spindle, and tailstock (lathe, drilling machine, milling machine, machining center, etc.), In order to ensure the machining accuracy of hole, the tool center must be aligned with center of preprocessed hole.
Tool rotation or workpiece are available, it depends on your choice, must be kept the tool rotation in positive (rotation according to the direction indicated by arrow on tool).
To increase service life of tool, please use coolant or cutting oil when processing.
Preprocessed hole that to be broached, which the diameter should be slightly bigger than or equal to the diameter of incircle of the polygonal broaching head (If there is the hexagonal hole, which the diameter should be larger than or equal to the opposite side distance); The preprocessed hole must be chamfered before broaching, and the hole diameter after chamfering should be bigger than the diameter of the excircle of the polygonal broaching head, which is convenient for tool guidance; The depth of preprocessed hole should be more than 1.5 times of the diameter of incircle of polygonal broaching head.
Keep the tool with low speed to contact workpiece, to increase the rotate speed when the broaching head in working state.
Machining Parameters:
Rotate Speed: 600-2000 rev/min
Feed Rate: 0.1~0.5 mm/r (For copper & aluminum materials, which feed rate should be increased by 2-3 times.)

Characteristics of NC cutting tools

NC cutting tools have many different requirements than those used in general machine tools.

The characteristics of NC tools are different from those of ordinary tools.

good rigidity (especially rough cutting tools), high accuracy, low vibration resistance and thermal deformation.
It has good interchangeability and is convenient for quick tool change.
Life is high, cutting performance is stable and reliable.
The size of the cutter is easy to adjust, so as to reduce the tool changing time.
The cutting tool should be able to reliably chip or chip, so as to facilitate chip removal.
Serialization and standardization are conducive to programming and tool management.

What are the characteristics of Flat Surface Roller Burnishing Tools?

Roller Burnishing Tool is a very important tool of the mechanical industry. There are many different roller burnishing tools on the market, which are prepared for different mechanical devices. Flat Surface Roller Burnishing Tool has been widely applied to recent years. Before using Flat Surface Roller Burnishing Tools, we should first understand the characteristics of Flat Surface Roller Burnishing Tools.

Flat Surface Roller Burnishing Tools, Flat Surface Burnishing Tool, Roller Burnishing Tools, Flat Surface Burnishing Tools Manufacturer, Flat Surface Burnishing Tools Exporter, Flat Surface Burnishing Tools Supplier, Cheap Flat Surface Burnishing Tools, Flat Surface Burnishing Tools for sale

Flat Surface Roller Burnishing Tools, Flat Surface Burnishing Tools, Flat Surface Burnishing Tools Manufacturer, Flat Surface Burnishing Tools Supplier, Flat Surface Burnishing Tools Exporter, Cheap Flat Surface Burnishing Tools

Features of Flat Surface Roller Burnishing Tools

(1) the surface roughness of the preceding procedure is not greater than 5μm, the surface before rolling should be clean, and the allowance of diameter is 0.02-0.03mm. With Flat Surface Roller Burnishing Tools, a single fine pressure can reduce the Surface roughness of the product from around Ra6.3um to between ra0.2-0.05μm, and only cast iron is between ra0.4-0.2μm.

(2) the precision of shape and the precision of mutual position of the workpiece after rolling mainly depends on the precision of shape position of the preceding procedure.

(3) generally, the rolled object is only suitable for plastic materials, and the material structure is required to be uniform. When the machined surface is rolled, its wear resistance is improved and its fatigue strength is increased by 30%. Flat Surface Roller Burnishing Tools can improve the tightness and eliminate the early wear, so that it has the advantages that cannot be obtained in machining.

(4) with mechanical fine tuning device, the deviation control is within 0.0025mm and the adjustment range of each is 0.5mm. High productivity, wide range of processing technology, not only can be used to process the outer round surface, for the inner hole, end surface processing can be used.