Speed ​​Reducer For 600,000-ton Full Continuous Bar Mill

1. Types and characteristics of speed reducers for 600,000-ton full continuous bar rolling mills

The speed reducer of the 600,000-ton class full continuous bar rolling mill is the proprietary technology of Pomeni, Italy, and its technical level is in a leading position in the world. The gears of the reducer all adopt hard tooth surface, the precision grade is DIN6; the box body adopts the steel plate welding structure. The overall structure of the reducer is reasonable, small in size, heavy and light, and large in transmission power.

Continuous rolling line reducers are divided into cylindrical gear transmission and conical cylindrical gear transmission according to the type of gear transmission; according to the installation position of the output shaft, it can be divided into two types: horizontal and vertical. Both gears and splines adopt DIN standards, and the gear material is 17CrNMo6. Fasteners adopt UN standards. The bearings are SKF bearings. The lubrication system of the reducer adopts a circulating oil centralized lubrication system, and the gear injection pipes are all in the box, and the lubrication conditions are good.

2. Working conditions of the speed reducer of a 600,000-ton full continuous bar mill

2.1 The maximum speed of the input shaft is not more than 1600r/trin

2.2 The gear circumferential speed is not more than 20m/s;

2.3 The working environment temperature is 0 and 5.C. If the environment temperature is too high or too low, cooling or heating measures should be considered.

3. Type of speed reducer for 600,000-ton full continuous bar mill

3.1 Structure type

The structure of the reducer of the Pomeny rolling mill is simple, the box body is a split structure, the gear seat gear is a helical gear, the output wheel is short from the bottom of the box body, and the transmission is stable. The typical structure of the horizontal horizontal reducer is shown in Figure 1, and the typical structure of the vertical vertical reducer is shown in Figure 2.

3.2 Installation type

The installation type of the reducer of Pomeny rolling mill is divided into two types: horizontal (H) and vertical (V).

3.3 Shaft end type

The input shaft end of the reducer of Pomeny rolling mill adopts cylindrical shaft extension and flat key connection; the output shaft end adopts DIN standard involute spline connection, which has high strength.

3.4 Models

There are 12 types of Pomeranian mill reducers, namely B1381, B1382, B1383, B1384, B1385, B1386, B1387, B1388, B1389, B1390, B1391, B139 2.

Figure 1 Typical structure of horizontal reducer

Figure 2 Typical structure of vertical vertical reducer

4 main technical parameters

4. 1 Center distance

Take the center distance of the output stage as the nominal center distance, see Table 1.
Table 1 : Nominal center distance of reducer

减速器型号

B1381

B1382

B1383

B1384

B1385

B1386

B1387 B

1388 B

1389 B1

390 B1

391 B1

39 2

名义中心距

580

400

4. 2 tooth profile

The bevel gear is Klingenberger spiral bevel gear, and the cylindrical gear is DIN3962 tooth profile.

4. 3 Transmission ratio

Each type of reducer has only one transmission ratio, which are 45.3467; 33.831025; 33.64035; 27.947368; 24. 21748; 18. 047255; 10.96953; 8.49282296; 7. 068; 5.45299806; 4.187; 3.333333.

4.4 Carrying capacity

Refer to Table 2 for the load-bearing capacity of the reducer of the Pomezni rolling mill.

Table 2 : Reducer carrying capacity

减速器型号	输入转速 / ( r / min)	输出转速 / ( r / min)	传动比	电动机功率 / kW	计算转矩 / ( N/ m)
B1381	200 – 700 – 975	4. 41 – 15. 45 – 21. 5	45. 3467	550	26000 0
B1382	200 – 700 – 975	5. 91 – 20. 69 – 28. 82	33. 831025	550	38000 0
B1383	300 – 900 – 1600	8. 9 – 26. 8 – 47. 6	33. 64035	950	38000 0
B1384	300 – 900 – 1600	10. 73 – 32. 2 – 57. 25	27. 947368	950	38000 0
B1385	300 – 900 – 1600	12. 38 – 37. 16 – 66. 07	24. 21748	950	38000 0
B1386	300 – 900 – 1600	16. 62 – 49. 87 – 88. 7	18. 047255	950	19000 0
B1387	300 – 900 – 1600	27. 3 – 82. 1 – 145. 8	10. 96953	950	16000 0
B1388	300 – 900 – 1600	35. 3 – 105. 97 – 188. 4	8. 49282296	950	10000 0
B1389	300 – 900 – 1600	42. 4 – 127. 3 – 226. 4	7. 068	950	10000 0
B1390	300 – 900 – 1600	55. 0 – 165. 05 – 293. 4	5. 45299806	950	6000 0
B1391	300 – 900 – 1600	71. 6 – 215 – 382. 1	4. 187	950	6000 0
B1392	300 – 900 – 1600	90. 0 – 270. 0 – 480. 0	3. 3333333	950	3500 0

5 Reducer appearance and installation dimensions

5.1 The outline dimensions of B1381, B1383, and 1385 reducers are shown in Figure 3.

Figure 3: Dimensions of B1381, B1383, and 1385 reducers

5.2 The outline dimensions of B138 2, B1384, and B1386 reducers are shown in Figure 4.

Figure 4: Dimensions of B1382, B1384, B1386 reducer

5.3 The outline dimensions of B1387 and B1391 reducers are shown in Figure 5.

Figure 5: Dimensions of B1387 and B1391 reducers

5.4 The outline dimensions of B1388, B1390, and B1392 reducers are shown in Figure 6.

Figure 6: Dimensions of B1388, B1390, and B1392 reducers

5.5 The outline dimensions of the B1389 reducer are shown in Figure 7.

Figure 7: Dimensions of B1389 reducer

6 Selection method of speed reducer for 600,000-ton full continuous bar rolling mill

The speed reducer of the high-speed tandem rolling line is a special reducer designed by Pomeranian for the bar rolling mill. Its structure breaks the mode of separating the main reducer and the rolling mill gear stand, making it one. The load capacity calculation of the reducer adopts the basic calculation method of AGMA involute spur gear and helical gear strength. The contact fatigue strength working condition coefficient is greater than 1, and the bending fatigue strength is greater than 1.4. The specific selection method can be directly contacted with the manufacturer.

7. Installation, use and maintenance of the speed reducer of the 600,000-ton full continuous bar mill

7. 1 Installation

7. 1. 1 The reducer before installation should have been tested on the test bench, except for the need to add lubricating oil before trial operation, all have the conditions for use.
7.1.2 Because the processed parts inside and outside of the reducer cannot be painted, they can only be protected with an antioxidant compatible with lubricating oil. This protective layer must be removed before installation and operation.
7.1.3 The lifting lugs or lifting holes provided should be used for the lifting of the reducer, and the steel wire rope should be used for lifting. When lifting a larger reducer, the steel rope should be hung at the bottom of the box below the marked line at the same time.
7.1.4 Before the reducer is connected to the lubrication system, save every easily damaged joint and accessory. Do not install it yet. Block the opening with a plug to prevent external debris from entering, and at the same time protect the internal parts Not affected by changes in external climate conditions.
7.1.5 The assembly of couplings, pulleys, gears and sprockets with the shaft should be connected with threaded holes. Do not use other methods to prevent damage to bearings or other parts caused by impact.
7.1.6 The transmission parts (such as couplings) on the shaft must be well aligned to prevent uneven operation and affect the operation of the reducer.
7.1.7 In order to make the reducer run smoothly, the reducer must be installed on a solid concrete foundation or metal base, and the appropriate bolts should be used to ensure that it can be adjusted and disassembled accordingly when needed.
7.1.8 In order to ensure the correct installation of the drive shaft of the reducer and its connecting equipment, the following points should be done: In order to make the reducer better align on the cement foundation, the corresponding anchor bolt holes in the concrete foundation should be placed in the concrete foundation. Set the embedded support plate at the position of the base; In order to prevent the deformation of the box structure caused by improper alignment during the installation process, the anchor bolt position should be leveled with a gasket; for the larger reducer, it is installed next to the foundation The bolts are equipped with adjusting bolts. Special attention should be paid to prevent poor gear meshing caused by the deformation caused by improper alignment; the meshing condition of the gears should be checked before the trial operation, and the contact of the driving surface of the gear should be checked after the reducer has been running for a short period of time. , Loosen the adjusting bolts after alignment and alignment; Since the bearing on the reducer is installed on the outside of the shaft, the alignment requirements of the reducer are more accurate, and any improper alignment will bring uncontrollable additional load to the drive shaft .
7.1.9 In order to prevent the box body from shifting under the action of external force, after aligning and tightening, the box body should be positioned with positioning pins or stoppers.
7. 1. 10 After installation, check whether all parts that should be checked are intact, including whether the oil inlet and outlet are unblocked.
7. 1. 11 If the reducer is installed outdoors, it should be covered with rain and sun protection, but be careful not to obstruct the air circulation near the box.
7. 1. 12 For safety reasons, the user should protect all moving parts with covers to prevent contact and injury.

7.2 Trial run

7. 2. 1 Check that the output shaft of the reducer runs freely in the correct direction. The direction of rotation may be one-way or two-way.
7. 2. 2 Before starting the reducer with anti-reverse device, check that the motor steering sensor and the direction marked on the box should be consistent. Wrong steering sensor will cause damage to the anti-reverse device.
7.2.3 The direction of rotation of the reducer shaft has been clearly marked on the diagram.
7.2.4 Check whether the input and output shafts of the reducer have axial movement, which will have an adverse effect on the operation of the reducer.
7.2.5 Check whether the above instructions are completed before the test run, especially if the lubricating oil has been added. Run the reducer for a short time under no load, then gradually increase the load to reach full load, and check the operation. At this stage, abnormal temperature rise may occur, mainly at the bearing. Normally, after 3 to 4 hours of operation, the temperature will return to normal. If it does not return to normal, the manufacturer should be notified.
7. 2. 6 Normal operating conditions
When the reducer adopts rolling bearings, the oil temperature usually does not exceed 80 ℃, the temperature of the bearing does not exceed 90 ℃, and the minimum oil pressure should be 0.05 ～
0. 07MPa. The maximum oil pressure is generally set at 0.35MPa by a valve, which is installed at the end of the lubrication circuit of the reducer.
Before trial operation, check whether all the system components equipped with electrical switches are in normal state, and allow transfer after normal operation. For the reducer with electronically controlled pump, the pump must be started first and its operating condition must be checked.
7.2.7 After starting the circulating oil centralized lubrication system, immediately check the lubrication effect and record the pressure, temperature and flow rate.

7.3 Lubrication

7. 3. 1 Confirm that the lubrication system has been installed.
7.3.2 Before driving, loosen the exhaust port or open the inspection port to inject oil to the calibration level.
7.3.3 The recommended oil grades are only applicable to normal production conditions and environmental conditions.
7.3.4 For those large gear units or those with poor oil pool lubrication effect, use a circulating oil centralized lubrication system for lubrication.
The system consists of a pump or electric pump, pressure gauge, temperature switch, filter, safety valve, oil flow indicator, pressure switch, etc.
7.3.5 When the heat cannot be effectively dissipated naturally, the lubrication system usually has oil-water or heat exchangers for heat exchange.
7.3.6 Before starting the centralized lubrication system, first confirm whether there are operating conditions and whether the system components with electrical switches are allowed to start.
7.3.7 During the first few hours of operation of the reducer, regularly check the turbidity of the oil and the particle size from gear wear. If necessary, replace the lubricating oil.
7. 3. 8 Use the same brand of lubricating oil as much as possible when changing the oil. The first oil change is carried out after 400-600h of operation, and every 5000-8000h thereafter. This means that the reducer is running at an ambient temperature of 45 ℃. If the ambient temperature is high, shorten the oil change interval. It is recommended to have a special laboratory to analyze and test the composition of lubricating oil to improve the adaptability of lubricating oil.

7.4 Maintenance

7. 4. 1 Clean the inside of the reducer, gears, shafts, etc. once a year, using a chemical cleaning agent that is less irritating. Then use the same grade of oil as that during production operation for flushing.
7.4.2 For the reducer of the circulating centralized lubrication system, clean the pipeline and filter and check the smoothness of the oil flow.
7.4.3 The wear of gears, bearings and seals should be checked regularly, and certain special electronic instruments should be equipped for preventive maintenance.
7.4.5 In order to prevent damage to the heat exchanger, even when it is not necessary to help dissipate heat in winter, it is necessary to keep a certain amount of water passing through the heat exchanger.
7.4.6 In the event of a failure, the manufacturer’s approval shall be obtained before disassembling the equipment for inspection or repair.
7.4.7 If the reducer is left unused for more than four months, its interior will evaporate and produce certain rust. To prevent irreparable damage to the bearings and gears, use the recommended anti-chlorinated oil and compatible with the lubricating oil.
7.4.8 Protection of the lubrication system in the idle state For pumps and electric pumps, disassemble the oil inlet and outlet pipe joints, and inject high viscosity into the pump.
Oil or grease. Use wood or wire plugs to block the oil inlet and outlet ports, fill the pipeline with oil and seal it. Flush with gasoline before restarting, and refill the pump with lubricating oil before starting.
For the filter, spray the anti-oxidant used to protect the processing surface onto the filter core and housing, and clean it with gasoline before restarting.
For oil-water heat exchangers, the inlet and outlet should be blocked.
For meters with electrical contacts, the meters are wrapped in plastic cloth, and the contacts are protected with silicon-based antioxidants.
7.4.9 For long-term storage, rotate the output shaft by hand for a week every 3 to 4 months to check whether all the protective layers coated with antioxidants are intact.