Centerless grinding machine H-4520

workpiecehorizontalNC

INTRODUCTION
The H Series is built around static pressure (hydrostatic) technology, offering high precision, low wear, and long-term stability to ensure consistent processing quality. The wheel spindle, regulating wheel spindle, and feeding axis (lower slide rail) are supported by a static pressure oil film allowing contact-free operation, preventing mechanical wear and maintaining high precision even during extended use. Its high rigidity and damping characteristics effectively reduce vibration, enhancing stability and surface quality during machining. The minimum feed rate is as low as 0.0005 mm, ensuring excellent roundness, surface quality, and dimensional accuracy of the workpiece.

CAPACITY
Standard Grinding Range (dia.): Ø1 ~ Ø45 mm
Grinding Wheel (O.D. x width x I.D.): Ø455 x 205 x Ø228.6 (7A) mm
Linear Velocity: 33 m/sec (45 m/sec)
Regulating Wheel (O.D. x width x I.D.): Ø255 x 205 x Ø127 (7A) mm
R.W. Speed: 10 ~ 300 rpm
Max. Infeed Length: 200 mm

MACHINE FEATURES
HIGH-PERFORMANCE GRAPHICAL USER INTERFACE
The control system features a teach-in Graphical User Interface (GUI) without program editing, providing a convenient operating environment. HMI with touch screen embeds shortcut keys for micro-feeding adjustment for easy grinding size adjustment.

RIGID MACHINE BASE
The machine structure is made of high-quality Meehanite cast iron, heat treated and stress relieved before machining. Slides are hardened by high frequency and precision ground. The stable structure resists deformation and offers excellent wear resistance.

ADVANTAGE OF HYDROSTATIC SPINDLE AND SLIDE RAIL
No metal-to-metal abrasion, improving machine service life. Extremely low metal friction and low temperature rise during processing reduce deformation, improving stability and component accuracy. High-pressure oil film supports high-speed rotation and ensures rotation accuracy.

OIL COOLANT SYSTEM
The oil coolant system includes an oil cooler to maintain constant oil temperature and prevent spindle accuracy variation due to oil temperature changes.

ACCUMULATOR FOR PROTECTION DEVICE
A special pressure accumulator design can return hydrostatic oil to the main shaft system when pressure drops (e.g., power failure), preventing damage from momentary loss of static pressure while the spindle is running.

HYDROSTATIC GUIDEWAY CONSTRUCTION
The regulating wheel lower slider (infeed axis) uses a hydrostatic guideway construction, providing extremely smooth and fast sliding movement, high precision feeding accuracy, and stable grinding accuracy. The lower feeding axis is driven by a servo motor with a harmonic reducer to reduce backlash, increase torque, and stabilize precision. Manual micro-adjustment minimum is 0.001 mm; numerical control minimum feeding can be set to 0.0005 mm.

STABLE GRINDING WHEEL AUTO DRESSING UNIT
The lower slideways of the grinding wheel dressing seat are a concave dovetail structure combined with an extra-large sideway to improve device stability.

DRESSING DEVICE OF R.W. & G.W.
Dressing structure is made of special alloy cast iron and heat treated for wear resistance. The dressing device is hydraulically driven front and rear and can be matched with a servo motor for profile dressing. Variable dressing speed and adjustable R.W. dressing to meet component accuracy.

AXIAL COMBINATION FOR NC SERIES
One axis: X-axis R.W. lower slide auto in-feed control. Two axes: Z-axis G.W. auto dressing (vertical) and X-axis R.W. lower slide auto in-feed.

SPECIFICATION
Capacity - Standard Grinding Range (dia.): Ø1 ~ Ø45 mm
Capacity - Max. Infeed Length: 200 mm
Capacity - Auto. Infeed Min. Increment: 0.0005 mm
Grinding Wheel - Size (O.D. x width x I.D.): Ø455 x 205 x Ø228.6 (7A) mm
Grinding Wheel - Linear Velocity: 33 m/sec (45 m/sec)
Regulating Wheel - Size (O.D. x width x I.D.): Ø255 x 205 x Ø127 mm
Regulating Wheel - Speed: 10 ~ 300 rpm
Tilt Angle: +5° ~ -3°
Swivel Angle: ±5°
Hand wheel Graduation - Upper Slide Feed: 4 mm/rev. (0.05 mm/graduation)
Hand wheel Graduation - Lower Slide Micro-Feed: 0.08 mm/rev. (0.001 mm/graduation)
Trimming Device: 2 mm/rev. (0.01 mm/graduation)
Drive Motors - Grinding Wheel: 7.5 kW (6P); Regulating Wheel: 3.5 kW (servo); Lower Slide Feed Motor (X-axis)(NC one axis): 1.0 kW; Lubrication Pump: 1.5 kW; Coolant Pump: 0.18 kW; Lubrication Oil Chiller: 0.37 kW
Tank Capacities - Lubrication Oil Tank: 90 L; Coolant Tank: 160 L
Machine Dimension (L x W x H): 3050 x 1710 x 1990 mm
Net Weight: 4300 kg

STANDARD ACCESSORIES

• Grinding Wheel and Flange x 1 set
• Regulating Wheel x 1 set
• Infeed Work Rest and Carbide Blade x 1 set
• Thrufeed Work Rest and Carbide Blade x 1 set
• Diamond Tools (2 pcs/set) x 1 set
• Electric System x 1 set
• Lubrication System (with an oil coolant and an accumulator) x 1 set
• Coolant System x 1 set
• Work Lamp x 1 set
• Tools (Leveling Pad) and Tool Box x 1 set

OPTIONAL ACCESSORIES

• Wheel Balancing Stand & Arbor
• Profile Grinding Attachment
• Grinding Wheel Ionization Dressing Device
• Hydraulic Work Ejector (Infeed Grinding)
• Manual Feeder For Infeed Grinding (Up and Down)
• Auto. Loading Attachment (Thrufeed Grinding)
• Automatic Feeder (Thrufeed Grinding)
• Auto. Unloading Attachment (Thrufeed Grinding)
• V Type Supporter for Long Bar Grinding
• Auto. Loading and Unloading Attachment (Infeed Grinding)
• Vibratory Feeder (Thrufeed Grinding)
• Fully Splash Guard
• Magnetic Coolant Separator
• Paper Filter
• Hydro cyclone Coolant Separator
• Jig Crank for Grinding Wheel

CARACTÉRISTIQUES / SPÉCIFICATIONS TECHNIQUES

• Model: H-4520-NC
• Standard Grinding Range: Ø1 ~ Ø45 mm
• Max. Infeed Length: 200 mm
• Auto. Infeed Min. Increment: 0.0005 mm
• Grinding Wheel Size: Ø455 x 205 x Ø228.6 mm
• Regulating Wheel Size: Ø255 x 205 x Ø127 mm
• R.W. Speed: 10 ~ 300 rpm
• Grinding Wheel Motor: 7.5 kW
• Net Weight: 4300 kg
• Machine Dimension: 3050 x 1710 x 1990 mm