The rebar roll is an important part of the rolling mill, which uses the pressure produced by a pair or a group of rebar rolls to mill different specification rebar profiles. The working environment of rebar rolls is bad, and many enterprises use cemented carbide as the main material of rebar rolls.

But the hardness of cemented carbide rebar is very high, the general tool is very difficult to process, Halnn superhard, as the forerunner of superhard tools localization, there are many years of practical experience in the field of rebar roll, Halnn superhard PCD notching tool is recommended for rebar roll crescent groove, under Halnn superhard according to the facturing process of rebar roll to introduce the choice of cutting tools and commonly used PCD notching tools specifications.

Manufacturing process of rebar roll:

Alloy preparation →pressing forming→ vacuum sintering and HIP hot isostatic pressing →ultrasonic non-destructive testing→ finishing →grinding inner hole→ grinding outer circle→chamfering→notching (including thread grooves)→laser marking→comprehensive inspection→packaging warehouse.

From the process, it can be seen that grinding is the main method in the manufacturing process, and the slotting process is mainly used in turning, including crescent groove cutting.

Selection of cutting tools for processing crescent grooves of rebar rolls：

At present, the new machining scheme of rebar roll crescent groove is to adopt flying tools groove structure, which gradually replaces the technology of swinging cutting head to cut crescent groove. The CNC rotary carving milling machine is adopted in the flying tools milling crescent groove, and the transmission, positioning clamping and manufacturing structure of the flying tools adopt a new functional structure to ensure high speed, stability and reliability, so that the crescent groove and transverse rib groove have superior processing efficiency, high precision and strong rigidity, and can easily process rebar roll crescent groove.

At present, the cutting tools for milling crescent grooves in rebar pass rolls are mature, called notching tools, which are mainly made of PCD material and also become PCD notching tools. Halnn superhard PCD notching tools with hardness above HRA88 can be easily machined.

Halnn superhard PCD rotary milling blade structure selection: PCD rotary milling tools has welding and veneer structure choice, diameter 4mm and above (up to more 9mm) choose welded structure, diameter below 4mm is mainly full veneer. And the PCD rotary tools Arbor generally can only use 2 milling tools, so you need to replace the new rotary tools Arbor.

Halnn superhard based on years of experience, summed up the conventional rebar roll crescent groove milling tools required PCD tools specifications:

The PCD notching tools of the following specifications are often used in No. 6 rebar：φ2.0*4.0*0.4*80°
The PCD notching tools of the following specifications are often used in No. 8 rebar：φ3.0*5.0*0.5*80°
The PCD notching tools of the following specifications are often used in No. 10 rebar：φ3.0*6.2*0.6*80°

The PCD notching tools of the following specifications are often used in No. 12 rebar：φ4.0*7.5*0.7*80°

Note: the PCD notching Arbor is generally only used for the milling of 2 PCD inserts, so it is necessary to replace the new Arbor to prevent excessive fatigue fracture and damage the workpiece.

Extended reading:

Halnn superhard introduction rebar roll crescent groove milling is also divided into new rolls and repair rolls.

The new roll can be processed according to the processing technology. for the repair roll, there are two ways to restore the use of the rebar roll, one is to change the roll groove from large to small, directly turn off the roll groove by grinding or turning, re-cut the groove and milling the crescent groove. The other is to repair and add material on the basis of the existing roll, the common methods are: surfacing welding, thermal spray welding, laser cladding, thermal spraying and so on. At this time, reprocessing is no longer the body of the roll, but the surface material. Therefore, the tools should be carefully selected when milling crescent slots.