You Ji YB-Series Large Spindle Bore CNC Lathes

Flat bed horizontal turning lathe



  • High rigidity Meehanite cast iron
  • High powered spindle motor
  • 3-step gear box with low speed & high torque
  • Large capacity spindle bore
  • X-axis and Z-axis driven directly by servo motor
  • Auto lubrication unit to extend the machine’s life
  • Choice of turret: HV, HL, HLC, and YC
  • FANUC Oi-TD CNC with proven the reliability and accuracy
  • Ergonomic design and easy to use operation panel
  • High volume flush coolant pumps
  • Coolant tank of the machine allows easy access for maintenance
  • Full enclosure guarding design for water-proof & dust-proof in accordance with CE regulations
  • A full strict quality control and test-cut.

Turn-Mill function (with C-axis and power turret)



  • General turning operations
  • Wind Mill industry ( main shafts )
  • Oil & mining industries ( oil pipes )
  • Aerospace industry (landing gears)
  • Rolling Mill industry (rollers )
  • Marine repair industry, mold industry,
  • paper industry, and long shafts

CF-axis System

cf-axis The servo motor combined with the brake system provides positioning accuracy, incorporating the power turret to allow for a wide range of work to be carried out.

Turn-Mill Function


Headstock and Spindle

Minimum Footprint
  • The solid box construction casting provides excellent rigidity for heavy cutting.
  • Spindle is fitted with double roller bearings and angular contact ball bearings to maintain excellent stability during the high speed.
  • Gear shift of spindle is controlled by M CODE automatically.
  • High grade nickel-chrome alloy steel gears in the headstock are hardened and precision ground.
  • Auto lubrication unit is fitted to headstock gears and spindle to maintain high accuracy and long machine life.


Minimum Footprint
(4-jaw manual chuck)
  • Modular design: 4-jaw manual chuck & 3-jaw hydraulic chuck are available.
  • 2nd chuck can be mounted on the rear side of spindle and achieves the best clamping support when the parts through spindle is machining.

Machine Base

Minimum Footprint

The box type design is used on the machine base which is made of Meehanite one piece cast iron and heat treated with a stress releasing process to keep the stable precision.

Cross Slide

  • Cross slide is made of Meehanite cast iron to provide stability and precision.
  • Large size work-piece can be supported by 3 wide span box guide ways and increase radial turning range.
  • Surface of box guide ways are heat treated and precisely ground incorporating laser calibration to ensure linear precision.
  • Each axes has Turcite B coated to reduce the friction factors and enhances feed rate capability.
  • Z-axis cross slide is driven by twin drive simultaneously to provide the maximum thrust.

Hydraulic Tailstock

Minimum Footprint
  • The solid box construction tailstock.
  • The quill is heat treated and precisely ground.
  • Taper roller bearings are used on the rotary quill providing the excellent support and stability.
  • Quill movement is controlled by program and adjusted by hydraulic valve to maintain the best part support.

Deep Boring Bar Holder

  • Can be mounted on X-axis cross slide and boring diameter & depth can be controlled by program.
  • It is designed for boring bar and boring bar holder in accordance with customer’s requirement.
  • Boring bar bushed can selected depending on the production requirements, various size can be supplied.

Steady Reset

  • Hydraulic and manual steady rests are available.
  • To get the best support and rigidity when machining the longer type of work-piece.

Electrical Cabinet

  • The control circuit in the electrical cabinet consists of high quality electronic components with auto power off system, and provides the best stability of control performance.
  • The electrical cabinet is fitted with an air conditioner to maintain the temperature, and extends the life of electronic components.


  • It is controlled by automatic central feeding device, and it can be set in accordance with volume and timing.
  • The alarm message can be displayed due to oil leakage in order to avoid any machine damage.

Chip Conveyor

  • Standard accessory is steel belt type chip conveyor.
  • Effective chip disposal is used with 2 chip conveyors on the front and rear side of the machines.

Machine Guarding Design

  • Full enclosure guarding prevents the chips & coolant fly out and protects the operators safety. A large movable door allows easy access for loading & unloading.
  • There is the maintenance door on the rear side of the machine.

Machine Specifications

ITEM Unit YB55 YB63 YB80
Capacity Max. turning length mm 3000 4000 5000 6000 3000 4000 5000 6000 3000 4000 5000 6000
Swing over cross slide mm Ø800 Ø1000 Ø1400
Swing over bed mm Ø1400 Ø1600 Ø2000
Max. turning diameter (cross slide) mm Ø800 Ø1000 Ø1400
Max. turning diameter (bed) mm Ø1100 Ø1300 Ø1700
Distance between centers mm 3200 4200 5200 6200 3200 4200 5200 6200 3200 4200 5200 6200
Travel X-axis travel mm 900 1100 1500
Distance between centers mm 3100 4100 5100 6100 3100 4100 5100 6100 3100 4100 5100 6100
Tailstock Quill diameter mm Ø170 (rotary quill) Ø170 (rotary quill) Ø250 (rotary quill)
Quill travel mm 250 250 250
Tailstock center MT6 MT6 MT6
Tailstock base movement Hydraulic Hydraulic Hydraulic
Quill movement Hydraulic Hydraulic Hydraulic
Feed rate X-axis rapid traverse mm/min 10 10 10
X-axis ballscrew dirameter mm Ø50xP10 Ø50xP10 Ø50xP10
Z-axis rapid traverse m/min 6 6 6
Z-axis ballscrew diameter mm Ø80xP10 Ø80xP10 Ø80xP10
Cutting feed rate mm/min 1~2000 1~2000 1~2000
Manual feed rate m/min 0~6 0~6 0~6
Motor Spindle motor kW 37/45 (∂ 40/6000i) 37/45 (∂ 40/6000i) 37/45 (∂ 40/6000i)
X-axis motor kW 4 (∂ 22/3000i) 4 (∂ 22/3000i) 4 (∂ 22/3000i)
Z-axis motor kW 6 (∂ 40/3000i) 6 (∂ 40/3000i) 6 (∂ 40/3000i)
Power capacity KVA 65 65 65
Tank capacity & Pump Coolant tank L 500 500 500
Coolant pump w 700 700 700
Lubrication pump w 45+45 45+45 45+45
Dimension Machine height mm 2,950 3,200 3,700
Machine length mm 4 (∂ 22/3000i) 4 (∂ 22/3000i) 4 (∂ 22/3000i)
Machine width mm 9380 10380 11380 12380 9380 10380 11380 12380 9380 10380 11380 12380
Machine weight kg 18000 20000 22000 25000 19000 21000 23000 26000 21000 23000 25000 28000

Standard Accessories and Optional Accessories

Spindle Spindle motor
3-steps gearbox
Rigid tapping
Work-piece clamping Hard jaws (hydraulic chuck)
Hydraulic tailstock
Tailstock center
Manual steady test
Hydraulic steady test
Foot pedal for tailstock operation
Chuck pressure
Programmable 2 step pressure control (chuck)
Programmable 2 steps pressure control (tailstock)
HV turret Face tool holderx2 sets
Boring bar holderx4 sets
Boring bar bushx1 set
HL turret Face tool holderx2 sets
Boring bar holderx4 sets
Boring bar bushx1 set
HLC turret BMT tooling
YC turret Capto tooling
Controller Fanuc Oi-TD
Fanuc 18i-TB
Coolant unit Oil skimmer
Level detector
Paper filter
Air gun
Coolant gun
Oil mist collector
Coolant cooler
Safety Full guarding
Door interlock
Overtravel switch
Overload monitoring system
Others Signal tower (3 stage)
Working lamp
Deep boring bar holder
Double chuck
Air conditioner for electrical cabinet
Hydraulic unit
Oil cooling fan
Hydraulic oil cooler
Auto lubrication unit
Tool box

Turret Specification (option)

Turret Type of turret H8 hydraulic turret
V4 hydraulic turret
H8 hydraulic turret BMT power turret Capto power turret
OD tool shank size mm ☐40×40 ☐40×40 ☐32×32 C6
ID tool shank size mm Ø63 Ø63 Ø60 C6
Drilling sleeve MT4, MT5 MT4, MT5 MT4, MT5 C6
Travel Y-Axis Travel mm N/A N/A N/A 100
Motor CF-axis servo motor kW N/A N/A 4 (∂ 22) 4 (∂ 22)
Y-axis servo motor kW N/A N/A N/A 4 (∂ 22)
Live spindle motor kW N/A N/A 7.5/11 (∂ 8) 7.5/11 (∂ 8)