CNC ROLL GRINDING MACHINES

MQK84200×100 CNC Roll Grinding Machine
 
Technical Attachment

Attachment 1: General description of machine
1.1 General instruction of machine MQK84200×100 CNC roll grinding machine is designed and manufactured by XianFeng Machine Tool Works, which based on the nearly 50 years experience in professional manufacturing roll grinding machine, and based on introduced the technical know-how of WALDRICH SIEGEN GERMANY. This CNC roll grinding machine has the features of high effective, high precision and safely operating, and the newest advanced controlling technology (Siemens 840Dsl) and transmission technology for the machine adopted mostly, The transmission technology and electrical controlling have achieved to the advanced lever of world.
The CNC roll grinding machine completely used advanced controlling technology and software to make the machinery construction of the grinder simplify relatively, the machinery transmission link reduced, the maintenance works reduced, and the reliability and flexibility comprehensively improved.
The newest advanced SIEMENS SINUMERIK 840Dsl system of world is applied for the machine, which matched with professional automotive controlling software and graphic operating interface (Chinese version) that has creative dynamical profile function in the progressing of grinding and measuring for the machine.
The machine matched with Siemens AC servo motor fully digital controlled, as to AC servo motor and AC spindle motor are of some advantage like high precision, free maintenance long-life and strong suitable ability. So the machine could be long-term operated in adverse circumstances.
Newly line grating from HEIDENHAIN GERMANY used for measuring roll to ensure the precision of measurement and position control.
Siemens AC servo motor serviced for carriage, wheel head, CNC curves grinding device and the transmission of measuring beam. The key bearings of the machine are applied with imported bearings (such as SKF, INA and FAG).
Main hydro parts (like pump, valve) are all from ATOS ITALY.

1.2 Shapes to be ground:

- Cylindrical barrel;
- Taper curves;
- Concave and convex curves;
- Arbitrary curves and CVC curves;
- Arc of two ends or straight line chamfer;

1.3 Technical conditions for the machine

1.3.1Working environment requires for the machine

Lowest temperature:  5ºC
Highest temperature:  45ºC
Humidity:  35%~90%
Humidity changes per hour ≤10%
Ambient temperature in cabinet:  22ºC±2ºC

1.3.2 Every media for the machine (such as Water, Electrical, Air)

Water :  clean water, cycling water (treatment)
Electricity: 3Phase, 400V (range: -5%~+10%), 50HZ (range: ±1%)
Air: Equipped according to the factory's standard

1.3.3 Information on ground properties

Bearing the weight of foundation:   ≥ 20T/
Water level of underground:  ≤  -3m
(the information of ground properties would be supplied by buyer after contract signed)

1.4 Performance rate of machine

1.4.1 Working time of machine

- Normal working time per working day is 20 hours for machine.

1.4.2 Adjusting time of machine

- Adjusting time is about 1.5 hours per working day for machine( such as checking the lubricants level, filling oil manually to lubricating points per working time, replacing wheel (if necessary), cleaning machine etc. And, it will take about 0.5 hour/time to replace steadyrest)

1.4.3 Maintaining (total and middle) per year and faults time

- Machine should be maintained regularly in normal performance, and regular maintaining could be adjusted according to the facts of machine, the time for maintenance (stop the machine) is about 5-7 days per year.
- The machine should be middle maintained in case of normal operation about 26000hours, which is mainly for adjusting and recovering the machine's accuracy, and will take 25-30 days/time.
The middle maintenance is mainly for the test accuracy of installation, and also for checking and replacing every transmission shaft and bearing; Checking and debugging electrical system; Replacing the hydraulic parts and pipes; Replacing the guideway with Teflon if needed, which is for aligning and correcting the accuracy of the guideway (only for reference)


List 1. List of roller for grinding

Attachment 2: Main construction features of machine

All photos are for reference only
Layout of machine
Main controlling axes definition of machine
From the drawings indicating above, main six control axes controls a complete CNC Roll Grinding Machine, two of them is main transmission axis, which are:
-   C-axis - work-piece rotating;
-   C1-axis - spindle of grinding wheel driving;
The others are servo driving axis:
-   U-axis - grinding head micro feeding (curve grinding);
-   Z-axis - Carriage longitudinal movement;
-   X-axis - wheel carriage movement;
-   X1-axis - measuring beam movement.

2.2 Structure and function for mechanical part

2.2.1 Bed

Two (2)-bed casting design, work side bed casting with headstock base, short distance between adjustable wedge shoes: Machine maintains its accuracy over a long period because rigid and separated beds ensure that there is no influence on the carriage bed when loading heavy workpieces on the workpiece bed.
- "Walk-on" telescopic way covers (when the carriage is stationary): Guideways are protected from harsh external environment; i.e. splashing water, dirt particles, etc.
- The two beds are of V-flat guide-ways with rectangle and trapezoidal type construction.

The V-flat guideway mounted on the upper of carriage, and a bearing of grinding wheel spindle and curves grinding mechanism inside. Hydro static guideway with under grips for cross feed guideway, driven by SIEMENS AC  servo motor via ball screw, high sensitive and stable traveling. The linear grating used to control the position loop of wheel head so as to realize closed-loop controlling.
                         
2.2.5 Spindle system for Grinding wheel

The spindle bearing of grinding wheel applied with hydro-dynamic/static bearing structure. The spindle rotated in the best rigid hydro-dynamic/static pocket which has high rotating precisions and rigidity. This spindle bearing could meet the requirements of rough grinding, fine grinding and finish grinding.
The spindle of G.W mounted in eccentric sleeve, and the sleeve mounted in the hydrostatic bearing of grinding wheel body. The hydrostatic bearing of eccentric sleeve distributed equal-are in the four pockets (upper, lower, front, rear). After pressure oil of throttle flew in to the pocket, the eccentric sleeve is in the center position of bearing bore, so that the lubrication formed between eccentric sleeve and grinding head body.
Stainless steel needle throttle for hydro-pressure throttle of G.W spindle which has good stable heat state.
V-belt used for driving G.W spindle. The thrust bearing (from INA) used for the axial bearing of grinding wheel spindle
And auto dynamic balancer (from MAPPOS ITALY) mounted in the G.W spindle to realize auto dynamic balance online.
2.2.6 Headstock                                                              
-V-belt drive: vibration-free drive even at high speeds
- SKF or FAG bearing from abroad used for the headstock
- Faceplate with floating driver: non-restrictive driving of rolls provides for optimum work piece surface finish.
- Lubricating ways is grease lubricating driven by a pump manually
 

2.2.7 Tailstock

Two section tailstock. The tailstock base is mounted on the work piece bed. It prevents axial displacement of the roll during the grinding process.
- Upper body of the tailstock along the base to adjust the horizontal accuracy of two centers perpendicularly to the centers' line.
- Large scale dimensioned and high rigid tailstock quill equipped with force pressure indicator and with dead center.
- Rapid movement along the guideway of work piece bed via worm, worm wheel by motor reduced to rack, gear, and driven by person also. If moving to the required position, the tailstock is fixed on the guideway of the work piece to meet different length of roll for grinding
- Motor driving or handwork for adjusting the tailstock's base and sleeve, mounted with individual control button, convenient and reliable.
The adjusting distance of sleeve is 300mm.
- The dresser mounted in the upper side of tailstock with diamond.
- The norm disk in the front side of the sleeve for measurement.
- The locking ways for tailstock and sleeve is manually.
2.2.8 Common steadyrest
To accommodate with different journal, each steady rest is equipped with various specification supporting blocks for supporting working rolls for grinding. The pads' location of the steady rest is adjusted by special measuring instrument for measuring pads' size, and the adjustment of the horizontal and the location of perpendicular supporting block is adopted with screw or slider for regulating. Casting the Babbitt to the pad, and lubricating with diluted oil which lubricant flows could be regulated; lubricating oil be collected and recycled which is to be reused by oil-water separator automatically. The movement of steadyrest and jaws adjusting are manually.
For easy of grinding part roller with bearings, a set of steadyrest with bearings will be designed, which could replace different pad according to different bearing chocks.

2.2.9 Grinding wheel dresser

The dresser for grinding wheel mounted in the tailstock's side, which is composed with a diamond and a norm block for measuring surface of roll and also a base plate. Simple structure and good rigid dressing. As the different trace for the surface motion of grinding wheel in the processing of dressing, straight line dressing and arc dressing could be realized.

2.2.10 Vertical rotate-able  operating panel

Equipped with a vertical rotate-able operating panel for easy operating the machine, a Siemens 15″LCD color monitor and keyboard.

2.2.11 CNC measuring system(with gratings)

- CNC measuring device with CP type. The diameter and curve shape of roll are measured by probe A and B, the measured results recorded by the CNC system automatically, and printed out by printer or displayed on monitor after the results processed by computer, and also the roll shape profile could be printed out.
- Measuring roll shape, roll diameter, roundness and cylindricity. Input measuring results to computer, the given curves, actual curves, error curves and compensation curves could be displayed on LCD monitor and the measured results could be printed out.
- The high precision measuring probes and long gratings are from HEIDENHAIN Germerny.

2.2.12 Removing and mounting for grinding wheel

  A set of static balancing stand for grinding wheel to the machine.
A set of specific hook for removing and mounting the grinding wheel

2.3 Structure designing features for hydraulics and cooling of machine

The hydraulic system of machine composed of hydro-dynamic/static lubrication of wheel spindle, hydro-static guideway lubrication of carriage and wheel carriage, lubrication system for jaws of steadyrest and cooling system. 

2.3.1 Lubrication and hydraulics system for spindle of machine

Transmission system of spindle lubrication and measuring beam hydraulics
- Accumulator could fill oil to the spindle when the machine is stopped to avoid the jaws damaged.
- The system using L-HM46 anti grinding hydraulic oil. the oil temperature of oil box is controlled by automatic constant temperature controller within in 30~40°C .
- The oiling pressure, oil temperature and cleanness degree could be inspected separately through pressure gauge, oil temperature inspector and oil filter, and the faults indicated by alarming.
- Oiling of the hydraulic system of measuring beam part is same oiling source. The actions carried out included mainly: the measuring arms of probe tips A and B upturned by 90°;
- The probe tips A and B contact with or away from the work piece, and are away from the work piece automatically when the grinding wheel is power off.
- Action of upturn of the measuring arms could be self locked.
- Back oil of the spindle bearing lubrication and the measuring beam hydraulics flowed into the back oil tank.
- The oil is drawn out automatically back to the oil box by a gear pump via a hydraulic-level switch and a delay.
- Guideway lubrication of the measuring beam used a hand pump, once an eight working hours
 

2.3.2 Lub. system for hydrostatic guideway of carriage and grinding carriage

The system using rated pump for oiling, which adjusted by overflow valve and transmitted to each hydrostatic pressure adjusting block and lubricating distributor through the pressure reducer, L-HG68 guideway oil used. Oiling pressure is 0.5-0.8Mpa.
- Helix throttle regulator for regulating the guideway's pressure of carriage and wheel head, the floating volume is about 0.005~0.015mm.
- The diluting oil lubrication ways from the multiple oil distributors is used fro lubricating the each transmission parts of the carriage and wheel head.
 

2.3.3 Lubrication system for jaws of steadyrest

   The lubricating system for jaws of steadyrest and spindle bearing used one oil box together, but the oil tank is seperated. Using L-HL68 hydraulic oil,  gear pump for oiling by 0.8Mpa with dropping lubricating, the oil volume could be adjusted separately, the lubricant could be retrieved interestedly via oil groove and also be re-used through the oil-water separator equipped with machine. The system also could lubricate for every transmission part of tailstock at same time.

2.3.4 Cooling system

- Coolant tank and magnetic roll and paper filter adopt. Water filtered by a magnetic separator, which flows 300L/min.
- The other two pumps with 3-phase, AB-200, 200L/min flows are used, one for grinding area via water pipe to nozzle on the grinding wheel cover, and another one for flushing the foundation pit.
- Diving pump is for drainage as for replacing the coolant in the cooling tank.
 

2.4. Functions for electrical controls of machine and hardware component

2.4.1 CNC host

The CNC host used new generation fully digital distributing SINUMERIK 840Dsl, S7-300 PLC insid, I/O interface outside of machine sent to the center control system via PROFIBUS; interface parts of Human-Machine is formed by new high effective module SINUMERIK PCU50.
       Siemens system configures as below:
NCU720.2 version
15color TFT Monitor OP015
PCU50.3 Human-Machine picture controlled
1.5GHz,512MB,using WINDOWS 7 system,80G,USB interface and mouse
S7-300 PLC inside,IM153 I/O interface.
S120 driven system

In case of updating system hardware, we would purchase the latest system to equip with machine.

2.4.2 Monitor system and keyboard

SIEMENS 15″color LCD OP015A used as operating monitor, CHINESE/ENGLISH display, the operating system used WINDOWS XP(English version). The system has complete alarming and diagnosing functions and also plentiful help and operation indication configured.

2.4.3  Human-Machine Interface software

We developed the specific HMI for the roll grinding machine based on SIEMENS HMI Programming Package, which is suitable for every special requirements of roll grinding machine, simple and clear operating picture. The system could simulating display of auto control and the processing of auto grinding and measuring; display curves program and measuring accuracy; and also printing and storage.
The main menu of the software formed with: System login, curves programming, machining programming, basic data setting, measured results managing, auto grinding, adjusting manually etc..

2.4.4  Servo system

The machine has four servo axes, they are carriage (Z-axis), wheel carriage (X-axis), curve grinding mechanism(U-axis), measuring mechanism(X1-axis), Siemens 1FT7 servo motor and S120 driven system are used.

2.4.5 Electronic handwheel

The electronic handwheel equiped for adjusting manually (Z, X, U and X1-axis) evey axis, the adjusting amount indicated precisely on monitor.

2.4.6 Controlling system for headstock

A spindle motor driven for headstock, an pulse encoder in-built which could realize loop control of headstock speed and position. The controlling system is SIEMENS driving system.

2.4.7 controlling system for grinding wheel

A spindle motor driven for grinding wheel , an pulse encoder in-built which could ensure high precise stable perfermance. The controlling system is SIEMENS driving system.

2.4.8 Measuring element

Equipped with high accuracy linear grating from HEIDENHAIN for the position full loop controlling of X-axis and X1-axis and roll measuring. The measuring system included two gratings which measuring range is 12 mm.
 

2.4.9 Specific cable

All control cables for CNC system, cables for servo motors, signal cables for encoder and linear grating are all from SIEMENS or HEIDENHAIN.
    
2.4.10 Cabinet
   The shell of cabinet which well-known brand in the world, protection grade IP54. The size of the cabinet is about 4400 × 600 × 2000mm.

2.4.11 Main motors

 

2.5 Main functions instruction

2.5.1 Self-suitable grinding functions

The self-suitable grinding function designed for the roll's feature of large wear in the middle and small wear at the two ends after the roll ground, using through grinding whole roll barrel after the two ends of roll is ground separately. In the procedure of grinding, current control is used (for controlling in feeding and reversing position), which means when grinding current is lower than the setting velum, the control system would send the signal of in feeding and reversing at once, following the grinding performance going, the reversing point of Z-axis is near to the roll center gradually, X-axis will be back away when the point is approaching to the point of the roll center, the grinding wheel would approach to the roll again from tailstock side and perform the self-suitable grinding from the tailstock side to the center of roll. When the self-suitable grinding is carried out to the roll center from the tailstock side, the system would be turned into grinding the whole roll barred.

2.5.2 Storage and manage for roll data

 The database of machine storied all current data of roll for the machine,
which includes diameter, roll shape, roundness, cylindriity, grinding curves and grinding technology, and also dimension and data of roll etc.. Before auto grinding, as to the roll number need to ground, pick up the current data from the database directly, then turn into auto grinding at once. After the grinding finished, the current data of roll could be storied automatically again, at same time these data could be sent to managing computer via net automatically to realize the unify management for several roll grinding machine in a roll workshop. The data of roll could be storied more than 1000 groups at least.
The machine has the interface to contact the managing system of roll workshop or the managing system of company(Ethernet interface or fibre interface),which could supply the fibre and electrical transfer(at the interface side of roll grinding machine) from the roll grinding machine to the managing system in the roll workshop or the managing system in company, these works should carried out by both parties(buyer and seller) together to login and commission.
The interface style and communication agreement between the roll grinding machine and the managing system in the roll workshop or in company should determined together in procedure of designing examination. 

2.5.3 Automatic measuring for G.W diameter

 The system could measure automatically the wheel's diameter under the control of the progressing. And also according to the diameter of wheel measured, to realize the function of auto constant cutting speeding control of grinding wheel and rapid approaching roll for grinding wheel.

2.5.4 Flexible control for cycle working of roll

Operator of machine could select the functions or links of auto grinding and measuring cycle according to the details of rolls.

2.5.5 Real-time simulation of grinding and measuring processing

In fully auto grinding, the system could display dynamic the procedure of grinding and measuring(real-time simulating) with figure besides regular displaying current, speed, coordinate location and working procedure etc. , so the grinding state is clear at a glance. And the machine could perform real-time measuring on line and auto compensating grinding.

2.5.6 Dynamic auto-compensation for mounting accuracy of roll

For improving the speed and accuracy of auto grinding and reducing adjusting time for machine, the dynamic auto-compensation function for mounting accuracy of roll developed specially. It working principle is: after the error of mounting accuracy of roll measured out, the CNC system could correct automaticaly given curves according to the data of mounting error so as to the aim to eliminate the mounting error of roll rapidly and precisely.

2.5.7 Rapid measuring function

In the auto cycle grinding of machine, the measuring system only check the roll barrel one time, the dimensions and size of diameter, shape, roundness, cylindricity etc. of roll could be measured at same time, and also display and print out the results(incl. : principle curves of roll shape and error curves).

2.5.8 Auto-alignment of tailstock position

In the procedure of the norm alignment for diameter measurement, grinding wheel dressing and grinding wheel diameter checking, the system will determine the position of each point (like norm disk and diamond) on the direction of Z-axis(it could not be influenced by the position changes of tailstock).

2.5.9 Auto compensation of G.W

The grinding wheel could peel off or wear out in the processing of grinding, but the control system of machine could aromatically compensate the wheel via measured results.

2.5.10 Chamfer grinding

When the rough grinding finished, the chamfer grinding progress could grind the chamfers for two ends roll. There are two chamfer types recently, they are arc interim chamfer and taper interim chamfer.

2.5.11 Another functions

(1) Grinding wheel could approach the roll surface automatically;
(2) Pre-selecting for G.W feeding automatically;
(3) Constant cutting speed control;
(4) Continuous automatic compensation for grinding wheel wear, period infeed;
(5) Grinding wheel is automatically away from the workpiece after power off for protecting the safety of person and equipment;
(6) Accuracy of reset for grinding wheel is 1μm;
(7) Auto cycle for grinding procedure;
(8) Auto measurement and the measured results are displayed and printed out;
(9) Curves compensation grinding;
(10) Faults diagnose;   

Besides CNC ROLL GRINDING MACHINES,also we can supply other machine tool below:
1.Roll Grinding Machines
2.Centerless Grinders
3.Large-type External Cylindrical Grinder
4.CNC Precision Double-Column Guidew AY Grinding Machines
5.Presses
6.Forging Rolls
7.Wedge-Roll Forming Machine