1. Machine mainly application and Basic components

1.1 Mainly application

This machine is a CNC heavy-duty horizontal lathe, suitable for applications in the energy, chemical, light industry, electromechanical, papermaking, aerospace, and aviation industries.

The machine is capable of performing various turning operations on large shaft-type workpieces (or cylindrical parts), including contoured surfaces and facing.

The machine is equipped with a single tool post, an automatic chip conveyor, and a tool cooling system.

Product schematic diagram (reference)

1.2 Basic composition

The standard configuration includes: workpiece bed, tool carriage bed, headstock, tailstock, saddle, box-type tool post, motor base, closed steady rest, open steady rest, cable carrier device, chip conveyor unit, hydraulic system, cooling system, and electrical control system.

The CNC system of the machine tool adopts the Siemens 828D CNC system. The spindle is driven by a servo motor. The longitudinal (Z-axis) movement is achieved through dual pinion-rack (helical gear) transmission, while the transverse (X-axis) movement is driven by a ball screw. The longitudinal and transverse movements of the tool post are both powered by AC servo motors. Both the X and Z axes are equipped with high-precision linear encoders from HEIDENHAIN (Germany) as position feedback devices, forming a closed-loop position control system.

2. Technical parameters

Technical Parameters

2.1 Main Parameters

2.1.1 Maximum swing diameter over bed .......................................................... φ2500mm～φ4000mm

2.1.2 Maximum workpiece swing diameter over carriage ..................................φ2000mm～φ3500mm

2.1.3 Maximum workpiece length ......................................................................... 8000mm～20000mm

2.1.4 Maximum workpiece weight between centers ................................................ 100t

2.1.5 Faceplate maximum torque ............................................................................. 125 kN·m

2.1.6 Tool post cutting force ................................................................................... 125 kN

2.1.7 Center angle ................................................................................................... 75°

2.2 Main Drive Parameters

2.2.1 Spindle speed steps (mechanical 2-range) .................................................... Stepless

2.2.2 Spindle speed range ...................................................................................... 0.63～120 r/min

2.2.3 Faceplate diameter ....................................................................................... φ2000mm

2.2.4 Spindle taper hole size .................................................................................. φ200 mm; 1:4

2.2.5 Spindle front bearing diameter ....................................................................... φ670mm

2.3 Feed Drive Parameters

2.3.1 Feed rate steps ............................................................................................... Stepless

2.3.2 Longitudinal feed rate of tool post ................................................................. 0.1～1000 mm/min

2.3.3 Cross feed rate of tool post ............................................................................ 0.1～1000 mm/min

2.3.4 Longitudinal rapid traverse speed .................................................................. 4000 mm/min

2.3.5 Cross rapid traverse speed ............................................................................. 3000 mm/min

2.3.6 Tool holder cross-section size ........................................................................ 80×80 mm

2.4 Tailstock Parameters

2.4.1 Tailstock quill diameter .................................................................................. 630 mm

2.4.2 Tailstock quill travel ....................................................................................... 200 mm

2.4.3 Tailstock quill movement speed .................................................................... 50 mm/min

2.4.4 Tailstock movement speed ........................................................................... 2000 mm/min

2.4.5 Tailstock spindle taper hole size .................................................................... φ200 mm; 1:4

2.5 Motors

2.5.1 Spindle servo motor power ............................................................................ 132 kW

2.5.2 Feed AC servo motor torque .................................................................. 1FT7 70 N·m, 1FT7 50 N·m

Speed ................................................................................................................. 2000 r/min

2.5.3 Tailstock movement motor power .................................................................. 7.5 kW

Speed ................................................................................................................. 1500 r/min

2.5.4 Tailstock quill movement motor power .......................................................... 4 kW

Speed ................................................................................................................. 1500 r/min

2.6 Main Drive System ............................................................................................. SIEMENS 6RA803.

3. Machine tool accuracy

Unspecified parameters shall comply with the Chinese national standard GB/T 23569-2009 "Test Conditions for Heavy-duty Lathes—Testing of the Accurac

4. Main structure of machine tool

4.1 Bed

The machine tool adopts a separated four-guideway layout with rectangular guideways. The total width of the bed guideways is increased, with two of them serving as the tool post guideways, featuring constant-flow hydrostatic guideways, and the tool post bed being fully enclosed. The other two guideways are workpiece guideways. The workpiece bed is partially enclosed according to the workpiece length, ensuring optimal force distribution, stable cutting, favorable tool post loading conditions, and suitability for heavy-duty cutting.  

Due to the separated bed structure, the deformation of the workpiece bed caused by workpiece gravity does not affect the tool post bed, maintaining original accuracy and ensuring machining quality.  

The separated four-guideway bed design isolates the main drive system from the feed drive system, preventing mutual vibration interference, which enhances machining quality and improves the machine tool’s vibration resistance.  

The four-guideway separated bed layout significantly reduces mutual thermal deformation effects, contributing to machining accuracy.  

The bed is supported on foundation leveling blocks and fixed with anchor bolts after adjustment. The workpiece bed and tool post bed are separately connected to the foundation, forming an integrated structure with good contact precision, ensuring guideway accuracy. Each bed can be adjusted independently for easier precision maintenance. Since anchor bolts and leveling blocks are installed every 500 mm along the bed, the connection stiffness between the bed and foundation is enhanced, resulting in higher overall rigidity, improved machining accuracy, and extended service life.  

A large space exists between the workpiece bed and tool post bed, facilitating the installation of a chain-type chip conveyor to discharge chips into a collection tank

                                                                                                                       Bed diagram

4.2 Headstock  

The headstock features a large-diameter through-shaft structure, driven by a Z-axis servo spindle motor. Through a mechanical two-speed gear shift, the spindle achieves the specified speed range. The main motor is connected to the main transmission mechanism via an elastic coupling. Power is transmitted through mechanical speed-change gears and helical gear pairs to the faceplate, enabling it to reach the required torque. All high-precision gears in the main transmission mechanism undergo hardening, grinding, and necessary profile modification.  

The spindle bearings use adjustable double-row radial short cylindrical roller bearings with controllable radial clearance. The spindle journal and locating taper hole are hardened and ground. The spindle center adopts a flange-type short taper shank center, secured to the spindle nose with screws and an interference-fit tapered surface, ensuring excellent rigidity and durability.  

A flow sensor is installed in the recess on the rear wall of the headstock to trigger an alarm when lubrication flow is insufficient. An encoder is mounted at the rear end of the spindle to enable feed-per-revolution, thread cutting, and constant surface speed machining functions.  

The headstock is equipped with an independent hydraulic control system and lubrication system.  

The headstock is mounted on the headstock base, which is in turn fixed to the machine bed.  

                                                                Schematic diagram of headstock transmission

Schematic diagram of Headstock

The headstock is equipped with an oil temperature-controlled tank that automatically regulates oil temperature to reduce thermal deformation of the headstock. A flow relay is installed upstream of the oil distributor for low-oil alarm, ensuring adequate lubrication for the spindle assembly and main drive mechanism. Temperature sensors are mounted at the spindle bearing locations inside the headstock to monitor bearing temperature rise. When excessive temperature rise occurs, the alarm system triggers a warning to alert the operator.

 4.3 Faceplate
The clamping of the workpiece is accomplished by four mechanical force-amplifying jaws at the front end of the chuck. The screw drive enables the jaws to rapidly approach the clamping position, and the workpiece is secured using the force-amplifying screw inside the jaw holder.

Schematic diagram of chuck

4.4 Tailstock

The tailstock consists of an upper body and a lower body. The housing is cast from high-quality low-stress cast iron. The upper body is equipped with a tailstock spindle, sleeve, force-measuring device, and sleeve movement mechanism, while the lower body contains the tailstock’s overall traversing mechanism.  

The lower body is driven by a BLD13-9-5.5 motor (P=7.5 kW) at a traversing speed of 2000 mm/min. The motion is transmitted via a motor → reducer → a pair of reduction gears → worm-and-rack mechanism, enabling movement along the workpiece bed. Upon reaching the desired position, the tailstock is clamped to the bed by two rows of disc springs in a mechanically clamped, hydraulically released manner. The worm-and-rack mechanism features an anti-backlash function.  

The upper body houses a hydraulic force-measuring device for the spindle. The sleeve has a diameter of  630 mm and a stroke of 200 mm. The tailstock sleeve spindle is supported at the front end by a double-row radial roller bearing, providing rigidity equivalent to that of the main spindle structure. The center is identical to the headstock center, adopting a flange-type short-taper shank center. It is secured to the mandrel front end via screws and an interference-fit tapered surface. The flange end face tightly presses against the mandrel’s front face, ensuring extremely high rigidity in the center system.  

Both the front and rear sides of the tailstock are equipped with an electrical contact pressure gauge. The preset pressure can be selected according to the workpiece weight by referring to the clamping force label. When the sleeve advances to clamp the workpiece, the sleeve movement motor automatically stops once the preset clamping force is reached.  

The tailstock body incorporates a hydraulic system that supplies pressure oil for clamping or releasing.  

Lubrication is provided by an intermittent, timed, quantitative automatic lubrication unit.  

                                                                                                       Tailstock schematic diagram

4.5 Saddle

The saddle consists of a longitudinal slide (Z-axis) and a cross slide (X-axis). The guideways for both longitudinal and transverse movements are two closed hydrostatic guideways each. The full hydrostatic system generates an oil film on the guideways, with appropriate oil pressure maintained between the oil pockets and the tool post to ensure flotation. The hydrostatic guideways are supplied by a dedicated oil tank equipped with an automatic oil temperature control system.

The saddle is driven by an AC servo motor, which transmits motion through a ratio gear and a bidirectional backlash elimination mechanism to a dual small helical gear-and-rack system. This drives the entire longitudinal slide along the Z-axis. The backlash between the dual small helical gears and the rack is eliminated by a disc spring cylinder pushing the central shaft. When there are minor variations in the rack pitch, the axial movement of the central shaft automatically compensates, ensuring zero-backlash meshing between the small helical gears and the rack. This guarantees high precision and stability throughout the tool post's movement. The longitudinal axis employs a high-precision, hardened Grade 6 rack.

The cross slide is driven by a single AC servo motor via a ball screw, enabling forward and backward movement along the transverse direction. It is equipped with a Heidenhain grating scale, forming a full closed-loop control system.

Both the longitudinal and transverse guideways of the tool post are fitted with telescopic way covers for protection.

4.6 Box-type Tool Post  

The box-type tool post is suitable for rough and finish machining of various shaft-type workpieces, particularly for heavy-duty cutting (rough machining) as well as machining step shafts, deep grooves, and end faces.  

This tool post mainly consists of a tool post body, large tool plates, and a tool plate movement mechanism. The tool plates are arranged on both sides of the tool post body and can extend and retract independently, secured to the tool post body via clamping plates.  

The tool plate movement is electrically driven, automatically clamping in place once the desired position is reached.

Appearance diagram of Box type Tool Post

4.7 Chip Conveyor
The machine tool is equipped with a chip conveyor installed between the two beds to transport chips and discharge them into a chip collection bin (the chip bin shall be prepared by the user).

4.9 Machine Hydraulic System

The hydraulic system of this machine consists of the following components:Headstock hydraulic system;Tool post and carriage hydraulic system (including the hydrostatic system);Tailstock hydraulic system

4.9.1 Headstock Hydraulic System

This hydraulic system primarily controls spindle speed changes in the headstock while also providing lubrication for bearings, gears, and other transmission components inside the headstock. The hydraulic power unit is mounted on one side of the headstock, with oil pipes routed from the power unit through trenches to the headstock. After lubrication, the oil freely flows back to the power unit’s oil tank via return pipes. To maintain the oil temperature within a stable range, an oil cooler is installed on the power unit to prevent adverse effects on machine performance due to excessive oil temperature.

4.9.2 Tool Post and Carriage Hydraulic System (Including Hydrostatic System)
The tool post and carriage hydraulic system mainly controls the following functions:Hydrostatic guideways for the longitudinal carriage (saddle) and cross slide;Clamping and releasing of the tool holder;Backlash elimination in the apron mechanism;

The hydraulic power unit is installed in a pit on one side of the tool post bed and serves as the power source for the tool post hydraulic system, as well as the supply and return station for the hydrostatic system. To ensure stable oil temperature, an oil cooler is installed beside the power unit, preventing machine performance degradation due to excessive oil temperature.

Hydraulic and hydrostatic oil pipes run through trenches and pass through the tool post cable carrier, connecting to the hydraulic control valve block and hydrostatic system mounted on the carriage.

Longitudinal Carriage and Cross Slide Hydrostatic System
The hydrostatic system for the tool post carriage consists of a control valve block and capillary restrictors. Hydrostatic oil is distributed through individual restrictors to the respective oil chambers of the longitudinal carriage and cross slide hydrostatic guideways, ensuring that both carriages remain in a hydrostatic floating state.

4.11 CNC System and Electrical Control System of the Machine Tool
4.11.1 The machine tool adopts the SINUMERIK 828D CNC system from Siemens.
4.11.2 The spindle is driven by a spindle servo motor equipped with a spindle encoder. The X and Z axes are powered by Siemens AC servo motors. The main operator panel features a color LCD display, which supports display functions and all basic operations of the Siemens SINUMERIK system, and includes a handheld unit (HHU).

4.12 Machine Tool Painting
The paint color of the machine tool shall be determined in consultation with the user before spraying.

5. List of main accessories

6. Supply list

6.1 Scope of supply of mainframe

6.2 Randomization data

7. The main national standards and industry standards adopted by this machine tool

All products of our company have a complete quality assurance system in the manufacturing process, from raw materials and purchased parts procurement, parts processing, inspection to assembly and debugging, and have passed ISO9001 quality system certification, and mainly abide by the following national standards:

8. Quality Assurance and After-Sales Service  

Our company has passed the ISO 9001:2000 quality management system certification. We take full responsibility for the quality of our products and shall be liable for any losses caused by design, manufacturing, or after-sales service deficiencies.  

 8.1 Manufacturing and Design Commitments  

a. In design and manufacturing, we strictly adhere to the technical agreement signed by both parties as well as relevant national and industry standards. Except for machine tool surfaces used for assembly, all metal exterior surfaces of components undergo anti-rust treatments such as chrome plating, zinc plating, bluing, or painting. We are responsible for repairing any surface damage incurred during transportation or installation.  

b. We guarantee that the equipment provided is technologically mature, reliable in performance, and advanced in capability.  

c. We take full responsibility for the quality of purchased electromechanical components and accessories.  

d. During equipment manufacturing, the buyer may conduct supervision and inspection.  

8.2 After-Sales Service Commitments  

a. Our technical personnel will provide training for the buyer’s operators and maintenance staff to ensure they can correctly operate, use, and perform routine maintenance on the machine tool.  

b. In case of quality issues during operation, we will respond within 4 hours (via phone, fax, or email) or dispatch personnel to the site within 48 hours, striving to resolve the malfunction within 3 working days. Our personnel will not leave until the issue is resolved.  

c. The warranty period  is one year after the final acceptance of the machine tool.  

d. We guarantee timely supply of required electromechanical spare parts, ensuring compatibility and interchangeability.  

e. During the warranty period, if any component fails under normal usage, we will replace it free of charge, with the replaced part covered by an additional one-year warranty.  

f. We provide lifetime technical support for equipment operation, maintenance, repair, and upgrades.  

9. Acceptance  

The machine tool acceptance is conducted in two stages:  

9.1 Pre-Acceptance  

The buyer shall arrive at the manufacturer’s facility within one week after receiving the completion notice. The seller will provide acceptance criteria, standards, and related documentation. Upon successful pre-acceptance, both parties will sign a Pre-Acceptance Report, after which the machine can be disassembled and shipped.  

9.2 Final Acceptance  

Final acceptance is conducted after installation and commissioning at the buyer’s site. Upon successful final acceptance, both parties will sign a Final Acceptance Report, marking the start of the warranty period. Key inspection items include:  

a.Geometric accuracy inspection  

b. Working accuracy inspection  

c. Functional performance testing  

d. Load capacity verification