Why Quality Bending Sleeves are the Secret to Long-Lasting Rebar Machinery
In high-pressure rebar fabrication, rebar bending sleeves (or bushings) are critical. They protect the central shaft and let rebar glide smoothly during bending.
Poor-quality, soft, or poorly heat-treated sleeves will groove or crack. This causes uneven bends and serious damage to your machine’s internal parts.
At Alas Machinery, our bending sleeves are built for extreme durability. We use Cr12MoV alloy steel and advanced processing. Below is a simple breakdown of the material’s chemical makeup and key features.
Cr12MoV Material: Chemical Composition & Key Properties
Cr12MoV is a high-carbon, high-chromium mold steel. It is known for its hardness, wear resistance, and toughness—perfect for heavy-duty rebar bending sleeves that handle repeated high-pressure impacts.
Chemical Composition (Weight Percentage)
We strictly control our Cr12MoV composition to meet GB/T 1299-2014 industry standards, ensuring consistent performance:
Carbon (C): 1.45% - 1.70% – Boosts hardness and wear resistance
Chromium (Cr): 11.50% - 13.50% – Improves corrosion and wear resistance
Molybdenum (Mo): 0.40% - 0.60% – Reduces internal stress; improves toughness
Vanadium (V): 0.15% - 0.30% – Refines structure; enhances hardness and stability
Silicon (Si): 0.20% - 0.40% – Increases strength and deoxidation
Manganese (Mn): 0.20% - 0.40% – Improves hardenability and toughness
Phosphorus (P): ≤ 0.030% – Minimized to avoid brittleness
Sulfur (S): ≤ 0.030% – Controlled to prevent defects
Core Mechanical Properties (After Vacuum Heat Treatment)
After our full-body vacuum heat treatment (quenching + tempering), our sleeves outperform ordinary alloy steels with these properties:
Hardness (HRC): 55 - 60 – Uniform throughout; no soft core
Tensile Strength (σb): ≥ 2000 MPa – Handles extreme bending pressure without cracking
Impact Toughness (αk): ≥ 25 J/cm² – No brittle fracture in cold or high-speed use
Wear Resistance: Better than 40Cr – Lasts 3-5x longer than standard sleeves
Dimensional Stability: ≤ 0.005mm/m – Tight fit with machine shaft; consistent bending
Corrosion Resistance: Resists rust and oil – Works well on harsh job sites
The Metallurgy of Survival: Vacuum Heat Treatment
Most aftermarket sleeves only have a hard surface (nitrided), with a soft core. This surface cracks under high-tensile rebar pressure.
Alas Machinery uses Full-Body Vacuum Heat Treatment. Combined with Cr12MoV steel, this process ensures:
Uniform Hardness: Consistent 55-60 HRC from outer to inner surface – No "out-of-round" deformation
No Internal Stress: Vacuum cooling eliminates stress – No cracking in cold or high-speed use (enhanced by Mo and V in Cr12MoV)
Precision Internal Grinding for Shaft Protection
A good sleeve must fit perfectly. A rough or oversized inner bore causes vibration and damages the machine’s main shaft.
Our Cr12MoV sleeves go through precision CNC internal grinding. This creates a "slip-fit" that reduces vibration and heat. It extends the life of both the sleeve and your machine.
Bespoke Spares, Direct from the Forge
Alas Machinery is a dedicated manufacturing facility
We make high-performance, maintenance-free spares ready for immediate use
Our Cr12MoV components fit perfectly and last longer than standard parts
Reduce downtime and boost production efficiency
High-Quality Rebar Bending Sleeves & Forming Bushings
Our Cr12MoV sleeves are built for extreme durability. They work with GW40, GW50, and GW60 rebar bending machines. They deliver consistent bends, protect the center pin and rebar, cut maintenance costs, and keep production running.
Key Advantages of Our Bending Sleeves
Premium Cr12MoV Material: Exceptional hardness, wear resistance, and pressure resistance
Wide Size Range: Fits international 4D/5D bending standards for all rebar thicknesses
Full Quenching & Tempering: Uniform hardness and stability – No deformation or cracking
Precision Fit: CNC-machined inner/outer diameters – Tight, wobble-free; extends machine life