Zhonggangpao-91Y

Zhonggangpao-91Y is a high-precision CNC machining equipment with a spindle bore diameter of 91mm, a maximum bed swing diameter of 720mm, an effective Z-axis stroke of 380mm, and a repeat positioning accuracy of ±0.002mm for X/Z axes.

It adopts an HT300 integrally cast bed, is equipped with a permanent magnet synchronous direct-drive spindle and a sine-cosine magnetic ring encoder, and is fitted with P4-grade bearings and C3-grade ball screws. The patented oil-cooled hydraulic station controls temperature to prevent deformation, and a liquid-cooled motor is optional. It can efficiently complete precision turning, milling and other processing, suitable for high-precision parts production in multiple fields.

Key Features

Technical Specifications

Case Study

We believe the projects that we have executed speak for themselves. CITIC HIC has engineered and provided 6 AG mills of Ø12.2m×11m (28000kW gearless drive) and 6 overflow discharge ball mills of Ø7.9×13.6m (2×9000kW gear drive) for Sino Iron Project in Australia. For Zijin Mining’s Duobaoshan Copper Mine project in Heilongjiang, we have manufactured and provided SAG mills of Ø11×6.4m (2×9000kW) and overflow discharge ball mills of Ø7.9×13.6m (2×9000kW) which have been well operating currently.

Machine tool model: Zhonggang Pao 91 type Y-axis turret lathe/chuck

Spindle: optional 46/52/65/75 type spindle units

Chuck form and motor model are determined according to working conditions

Kind reminder: 1. Due to the possibility of personalized customization in appearance, the actual product shall be subject to the graphic and video files recommended by pre-sales staff; 2. There may be slight errors during assembly, and the actual dimensions shall be subject to the measured data.

Z-axis Milling Processing Parameters

Measurement Dimension \ Spindle Bore	Tool Turret Processing Length L1 (Chuck End Face – Power Head Center Position)
	Spindle Head – Power Head	Chuck – Power Head
Zhonggangpao-46Y	390mm	377mm
Zhonggangpao-52Y	380mm	363mm
Zhonggangpao-65Y	380mm	350mm
Zhonggangpao-75Y	375mm	349mm
Zhonggangpao-91Y	375mm	333mm

Machine Tool Highlights

Serial Number	Core Component	Process Standards and Requirements
1	Bed Casting	HT300 integral casting + tempering + natural aging for > 90 days
2	Guide Rail Mounting Surface Processing Precision	Adopting semi-finishing + finishing process, 1m vertical line ≤ 0.01mm, side line ≤ 0.005mm
3	Ball Screw Pair	Randomly equipped with Yintai & 凯特 (Kate), ≥ C3 grade, double-nut structure
4	Guide Rail Pair	Randomly equipped with Yintai & 凯特 (Kate), ≥ P grade, flange slider
5	Ball Screw Bearing	Koyo, P4 grade. Mingda can provide: same as Beijing Jingdiao & Chuangshiji
6	Spindle Unit	Permanent magnet synchronous rear direct-drive integrated type, with small mechanical load, low heat generation, high coaxiality, and better realization of high speed, high precision, and high rigidity. Moreover, the motor and bearing have long service life and simple maintenance.
7	Spindle Encoder	Adopting sine-cosine magnetic ring encoder, ensuring smoother operation and higher positioning accuracy
8	Spindle Bearing	Custom-made for fine machine tools: domestic well-known brand, P4 grade
9	Oil Cylinder & Chuck	Custom-made for fine machine tools: domestic well-known brand
10	Oil-cooled Hydraulic Station	Patent No.: 2025218556078 Working Principle: On the basis of an ordinary hydraulic station, a 2700W refrigeration system for cooling capacity is added. The hydraulic oil in the hydraulic station tank is cooled and then delivered to various pipelines that need hydraulic oil, realizing their respective functions in a relatively low-temperature state, effectively controlling the precision error caused by the thermal extension of the machine tool, and prolonging the service life of related functional components.
11	Lubrication System	Special alloy steel gear pump + volumetric oil discharge, automatic pressure relief structure
12	Low-voltage Electrical Components	Schneider + Tengen + Mean Well, ensuring genuine products
13	Oil Circuit	Using smooth steel wire pipe with an anti-burst pressure of 54MPa
14	Water Circuit	Using steel wire oil pipe with an anti-burst pressure of 45MPa, equipped with a filter as standard
15	Internal Protection	SUS201-J1 grade plate, cutting precision < 0.05mm, suspended structure. When running in the Z direction, the friction system is small, the machine tool vibration is small, and the motor load is small. It reduces the surface roughness of the outer circle and improves the linkage precision between the Z direction and other axes.
16	External Protection	National standard 2.0 cold-rolled plate + outdoor powder spraying process + 304 door hinge. Heavy, anti-vibration, and durable
17	Control System	Tiesi Series A Controller + EtherCAT communication method, “fly-read fly-write” mechanism, realizing microsecond-level communication synchronization (optional)
18	Liquid-cooled Axial Motor	Power Head Motor: standard liquid-cooled type; Feed Axis Motor: liquid-cooled type optional for the X direction of the gang tool lathe. Advantages: effectively control motor temperature rise, reduce precision errors caused by machine tool thermal extension, and prolong the service life of motors, ball screws, and bearings.

Main Technical Parameters

Serial Number	Item	Unit	Parameter
1	Maximum Swing Diameter of Bed	mm	720
2	Maximum Swing Diameter of Saddle	mm	480
3	Spindle Pull Tube Bore Diameter	mm	91 (optional 46/52/65/75)
4	Spindle Nose / Chuck	–	A2-8/3-jaw 12-inch chuck
5	Spindle Oil Cylinder Model	–	Hollow 1291
6	Permanent Magnet Synchronous Direct Drive Motor Model/Power/Speed/Torque	–	A8-22-210N1020-K115
7	Effective Stroke of X Axis	mm	250*2 (movable dimension of linear guide)
8	Effective Stroke of Z Axis	mm	380 (movable dimension of linear guide)
9	Limited Stroke of Y Axis	mm	±50 (movable dimension of linear guide)
10	Rated Torque of X/Z/Y Axis Motors	N.m	11.5/15.2/11.5
11	Maximum Moving Speed of X/Z/Y Axes	mm/min	25000/20000/25000
12	Rated Torque of Power Head Motor	N.m	11.5 (with liquid cooling, optional 8.4/15.2)
13	Maximum Speed of Power Head Motor	r/min	5000 (optional 6000/4000)
14	Guide Rail Specification of X/Z Axes	mm	35 extended rectangle / 35 extended flange
15	Ball Screw Specification of X/Z Axes	mm	3210/3210
16	Repeat Positioning Accuracy of X/Z Axes	mm	±0.002mm
17	Minimum Setting Unit of X/Z Axes	mm	0.001
18	Tool Turret Specification	–	BMT45-15 stations (no option)
19	Power Tool Holder Specification	–	BMT45
20	Ordinary Tool Holder Specification	mm	25*25+Ø32
21	Machine Tool Dimension (Length × Width × Height)	mm	218516851965 (excluding warning light)
22	Gross Weight of the Whole Machine	kg

Brazilian Miner Vale SA

23 large-scale ball mills, Ø5.5×8.8m

Wengfu Phosphate Mine Project Phase II in Saudi Arabia (Ma'aden)

6 wet grinding rod mills, Ø4.6×6.7m

Vedanta Project in South Africa

1 SAG mill, Ø8.5×5.5m

Laos Phonesack Group's KSO Gold Mine Project (83,000t/d)

6 SAG mills, Ø8.8×4.8m

Mongolian Erdenet Mining Corporation's Copper Mine Project (20,000t/d)

SAG mill, Ø9.75×4.88m

Full-process Solution for Mineral Grinding

Why Choose CITIC HIC's Grinding Mills

High cost-effectiveness
CITIC HIC grinding mills are recognized as China’s Manufacturing Industry Single Champion Product. CITIC HIC is responsible for setting the national standards of semi-autogenous mills (SAG mills) and ball mils, supported by powerful database, optimized process technology, cutting-edge design concept, and 60 years of experience in developing and nurturing innovative technology.
High operating rate
The long life cycle of our products is based on the adoption of international standards, high-quality materials, state-of-the-art processing techniques.
Low-carbon & environmental-friendly processes
Intelligent control technology coupled with long-life wear-resistant materials results in low-carbon and eco-friendly operations.
High-efficiency service
Our service network is distributed all over the world, and our service team of seasoned professionals is reliable and willing to assist along the way. We are able to deliver quick response to customer needs and provide full life cycle support via online monitoring and diagnosing, product upgrading and continuous process improvement.