Phone:
86-15852949220
NANJING ALAS INTERNATIONAL CO., LTD
 |
| Quantity: | |
|---|---|
In modern construction, a structure’s strength depends on its rebar. Rebar thread rolling dies are key for making strong mechanical splices. Thread rolling is better than traditional thread cutting. To get the best results, you need to understand the die’s working principle, types, specifications, selection and installation.
Three thread rolling dies spin at the same time.
They press the rib-stripped end of the rebar from all sides.
The rebar’s surface metal bends to form continuous straight threads.
Threads are stronger than the original rebar because cold rolling makes the metal harder (no cut grain flow).
Joints can handle the high tension needed for earthquake-resistant and heavy-duty projects.
75°: Thick thread root, strong and wear-resistant. Best for HRB400E/HRB500E high-strength rebar (most common choice).
60°: Sharp thread, easy to fit and pass inspections. Wears out fast, mostly used for HRB335E ordinary rebar.
Numbered Dies (No.1/2/3): For lead-angle thread rolling machines. Install by number—cannot be swapped.
Integral Dies (Unnumbered): Universal, can be swapped. Easy to maintain, for non-lead-angle machines.
Standard Grade: Made of 9CrSi. Lasts for about 2000–3000 thread ends. For HRB335E rebar.
High-Strength Grade: Made of Cr12MoV / DC53 (vacuum quenched). Lasts 5000–8000 thread ends. For HRB400E/HRB500E rebar. Hard and wear-resistant, reduces downtime in big projects.
Pitch P(mm) | Applicable Rebar Diameter(mm) | Common Model |
2.5 | φ12、14、16、18、20、22 | A25 |
3.0 | φ25、28、32 | A30 |
3.0/3.5 | φ36、40 | SA30 |
Rebar Grade: Use 75° high-strength dies (Cr12MoV) for HRB400E/HRB500E to ensure enough strength.
Diameter Matching: Use P2.5 for rebar ≤22mm; use P3.0 for rebar ≥25mm. This ensures a good fit with rebar couplers.
Machine Adaptation: Lead-angle machines need numbered dies; non-lead-angle machines need integral dies (easier to maintain and swap).
Adjust the gap between the three dies at the same time. This ensures threads are aligned and full.
Precision is important for a tight fit with rebar couplers (avoids loose connections or cross-threading).
When changing dies, check the pitch washer and eccentric sleeve position. Wrong installation causes messy threads.
Cold rolling moves metal (instead of cutting it), keeping the steel’s grain flow continuous.
This makes threads harder and stronger than the original rebar.
Joints meet or exceed tension requirements for important construction projects.
A common problem: making sure threaded ends fit rebar couplers well.
Precision-ground dies keep tight control over pitch and thread size.
Ensures a secure fit, avoiding cross-threading and loose connections (common with poor-quality tools).
Big projects (bridges, high-rises) lose money if tools need frequent replacement.
High-strength dies (Cr12MoV / DC53, vacuum quenched) last 5000–8000 thread ends.
With proper lubrication and adjustment, they cost less per thread than standard or poor-quality dies.
Die quality affects your production speed and structure safety. Learn about die types, specifications, selection and installation. Choose high-quality, precision dies made of strong alloy steel. This ensures faster work, stronger joints and long-term cost savings—all key for successful construction projects.
Nanjing Alas International Co., Ltd. is a professional industrial tooling manufacturer focused on shear blades, bending dies, shredder blades, and custom wear parts. We offer full application engineering, material selection, setup guidance, and after-sales support to global customers.
Tell us your requirements, and our engineering team will provide professional solutions for blade specification, tool life optimization, and cost-effective production.