Professional Rebar Bending Bushings (Comprehensive Size Range)
Introduction to Rebar Bending Bushings
Our high-quality rebar bending bushings give consistent, accurate bends. They fit the center mandrels of GW40, GW50, and GW60 machines, and control rebar bending radius. As key custom rebar bender parts, they work with most semi-automatic and fully automatic CNC rebar bending machines.
Rebar bending bushings are vital parts of rebar processing machines. They affect bending accuracy, product quality, and machine efficiency. Using the three-point bending method, they bend different rebar sizes into shapes needed for construction (e.g., stirrups, beam and column reinforcement).
Definition and Principle
What Are Rebar Bending Bushings?
Rebar bending bushings are special molds on rebar bending machine discs. They have three main parts: a central bushing, a movable bushing, and a positioning bushing. These three work together to form a standard three-point bending system.
They bend rebar precisely when moving together. You can change bushings to fit different rebar diameters, making them flexible custom rebar bender parts.
Working Principle
Rebar bending bushings use the three-point bending method. Rebar is held tightly between the central and positioning bushings. The machine moves the movable bushing to apply even pressure to the rebar.
This pressure bends the rebar around the central bushing. Change the central bushing’s diameter to adjust the bend radius. The machine’s disc rotation controls the bend angle (0-180° adjustable).
Main Specifications
Types by Function
Rebar bending bushings have three types by function: central, movable, and positioning.
The central bushing is fixed at the disc center, guiding the bend and setting the smallest bend radius. The movable bushing applies force and controls the bend angle, with an adjustable position. The positioning bushing keeps rebar from moving during bending—all key features of good custom rebar bender parts.
Types by Rebar Size
Bushings are grouped by the rebar diameter they fit, with four types:
Small: For 6-16mm rebar (stirrups, small precast parts)
Medium: For 18-28mm rebar (main structural rebar in beams, slabs)
Large: For 32-50mm rebar (columns, shear walls)
Special: Custom custom rebar bender parts for irregular rebar, high-strength steel, and HRB500 grade steel.
Key Parameters
Bushing parameters must match industry standards, machines, and materials. Key details:
Outer diameter: 30-100mm (fits 4D/5D international bending standards)
Bushing diameter: 25-120mm (1.5-5x the rebar diameter)
Width: 15-50mm (depends on rebar size and number per bend)
Shaft hole diameter: 16-40mm (fits the machine’s disc shaft for stable installation)
Materials and Manufacturing
Common Materials
Bushing material affects hardness, wear resistance, and strength. Main options:
40Cr alloy steel: Chemical composition (approx.): C 0.37-0.44%, Cr 0.80-1.10%, Si 0.17-0.37%, Mn 0.50-0.80%. Composition impact: Cr boosts hardness/wear resistance; C enhances strength; Si and Mn improve toughness. Performance: High strength, good toughness, no cracking/deformation under pressure; suitable for regular rebar processing.
Cr12MoV alloy steel: Chemical composition (approx.): C 1.45-1.70%, Cr 11.50-13.00%, Mo 0.40-0.60%, V 0.15-0.30%. Composition impact: High C/Cr ensures high hardness/wear resistance; Mo/V improves heat resistance and dimensional stability. Performance: High hardness, wear-resistant, stable; ideal for long-term standard rebar bending.
Manufacturing Processes
Precision manufacturing ensures accurate bends. Key steps:
Precision forging: Makes the bushing strong and impact-resistant
Induction hardening: Hardens the bushing for long-term use in construction
Vacuum heat treatment: Hardens evenly without bending
Precision grinding: Ensures a tight fit; diameter error is within ±0.02mm.
Maintenance and Replacement
Daily Maintenance
Simple daily care extends bushing life:
Before use: Check if it’s installed tightly and clean off debris, rust, or oil
During use: Follow rules; don’t overload or bend oversized rebar
After use: Clean and apply anti-rust oil to shaft holes—important for keeping custom rebar bender parts in good shape.
Regular Maintenance
Check weekly for batch processing:
Take bushings apart to clean and check for wear, cracks, or bending
Check fit and lubricate moving parts; replace old lubricant
Polish small wear spots; store in a dry, well-ventilated place.
Repair and Replacement Rules
Fix or replace based on wear to keep quality high:
Fix or replace based on wear to keep quality high:
Small scratches: Polish or grind to fix
Severe wear, cracks, or misalignment: Replace right away
How often should I replace rebar bushings?
There is no fixed time for replacement, and it depends on usage frequency, processing rebar specifications, and material of the bushing.
For regular use (daily batch processing): 40Cr bushings usually need replacement every 3-6 months; Cr12MoV bushings, with better wear resistance, can last 6-12 months.
Replace immediately if any of the following occurs: severe surface wear, chipping, cracks, groove deformation, shaft hole misalignment, or uneven bending results.
