GOST认证FAML-4 Load-Haul-Dump技术要求
CHAPTER 1 Brief Introduction of FAML-4 LHD
I General
Since 1984, Load-Haul-Dump (LHD for short hereinafter) Workshop has co-operated with the famous foreign LHD manufacturers and manufactured 69 sets of LHD of 1.7m3, 3m3, 3.8m3 and 6m3. Then united some domestic relative scientific research institutes and customers, LHD Workshop has constantly designed and made more than 20 sets of LHD with the sizes of 1.5m3, 2m3, 3m3 and 6m3, since 1994. Based on the experience of manufacturing LHD for many years, especially on having manufactured 2 sets of LHD with the bucket capacity of 3.8m3 together with the Wagner company of USA in 1990, LHD Workshop has successfully developed FAML-4 LHD with the bucket capacity of 3.5~4m3 in 1995. FAML-4 is a new type of LHD, which is developed by absorbing the successful experience of manufacturing LHD at home and abroad, adopting the advanced and mature technique and structure from abroad, and combining with the particular condition of LHD Workshop.
FAML-4 LHD has become a sub-item (Project No: 95-116-03-04-01) of the first group of national key scientific brainstorm project named “Study on the Comprehensive Technique for Enhanced Exploitation of Deep and Difficult Mine Beds” (Job No: 95-116).
II Main Technical Data
i. Overall Dimension (Fig. 1)
Fig. 1 Overall Dimension of CY-4 LHD
ii. Technical Data of LHD FAML-4
Function Rated Load（t） 9.5
Std.
Bucket Std. Bucket Capacity（m3） 4
Struck Capacity（m3） 3.1
Optional Capacity（m3） 3.5
Breakout
Force SAE Std.（KN） 120
Max.（KN） 196
Tipping Load（fully turned）（KN） 200.4
Max. Pull Force（KN） 185
Time of Bucket Movement Time From Transportation Pos. to Highest Pos. (s) 6
Time for Loading & Dumping (s) 3.2
Operational Weight (t) 22.5
Engine Type / Size DEUTZ BF6M 1013ECP
Rated Power (2300r/min)(kW) 176
Method & Size of Exhausting & Purifying Catalytic Purifying 7DZ
Transmi
-ssion Type Mechanical Power Shifting
Manufacturer / Size Clark R32421
Ratio (Shift1~4) 4.73，2.23，1.29，0.75
Torque
Converter Type Single-stage Triple-element
Manufacturer / Size Clark 5402
Torque Coefficient 3.14
Front &
Rear
Axles Type Planet Rigid Axle
Total Ratio 29.95
Manufacturer / Size Clark/19D2748
Tire Type L5S Type, No Inner Tires
Size 18.00×25
Qty. of Layers（layer） 28
Oil
Pump Steering / Brake Pump Type Duplex Gear Pump P315
Manufacturer Imported from COMMERCIAL
Flow rate (n=2300r/min) (1/min) 82（Steering）64（Brake Cooling）
Service
Oil
Pump Type Single-stage Gear Pump
G30-4D25C-12AL
Manufacturer Purchased
Flow rate (n=1200r/mir) (1/min) 94.5 49
Transmis-sion
Cooling
pump Type Single-stage Gear Pump
Manufacturer Clark
Flow rate (n=2000r/min) (1/min) 79
Cylinder Steering Cylinder (Rod×Stroke×Piston Rod Dia.) (mm) Ø110×372×Ø50
Hoist Cylinder Ø150×820×Ø75
Dump Cylinder Ø200×1403×Ø100
Service
Parking
Brake Type CLARK posi-STOP
Size LCB16150
Volta-ge
Syst-
em Voltage（V） 24
Batte-ry Qty.（pieces） 2
Type（V） 12
Capacity（Ah） 165
III Characteristics of the Main Structure
i. Driving System (Fig. 2)
Fig.2 Sketch for the Driving System of LHD FAML-4
1. Diesel Engine, DEUTZ-BF6M 1013ECP, Germany
2. Torque Converter, ClarkC5402
3. Rear Driving Shaft
4. Transmission, ClarkR32421
5. Shifting Lever
6. Clark POSI-TORQ Differential
7. Front Axle, 19D2748
8. Clark NO-SPIN Differential
9. Rear Axle, 19D2748
10. Tire, L5S 18.00×25 PLY28
11. Front Driving Shaft
Fig.2 shows that, key parts of the driving system, such as the diesel engine, torque converter, transmission and front & rear axles are imported, so as to ensure the reliable quality, stable function, few trouble and long service life to the whole driving system. Done in such way, it is mainly considered the foreign manufacturing experience of LHD, the current domestic technical level in manufacturing and the quality requirement of users to LHD.
ii. The POSI-TORQ differential is used for the front axle, and the NO-SPIN differential for the rear axle, which is a newest and the most advanced disposition of the foreign LHD at present.
There are many reasons which caused the unequal stokes of left & right wheels during traveling of the underground LHD, i.e. when turning aside or traveling straightly, the strokes of both wheels will be different. In this case, if both wheels are driven by one shaft at the same speed, the LHD will certainly be slippery on the ground, and as a result of which, the attrition of wheels will increase, and as well as the loss of power. In addition, the operability will become poor. So the differential should be disposed for the LHD. The common differential (common bevel gear planet differential) is harmful to the traveling and operation of LHD because of its driving characteristic of “difference speed only but not torque”. If one wheel has been trapped in mud, it will be slippery because of its insufficient adhesion. At this time, the drive torque of other wheel will be reduced to the same of the slippery one instead of being increased, so that the traction power of the whole machine will be greatly reduced. If the total traction power is reduced to be insufficient to overcome the traveling resistance, then the slippery wheel is rotating at a speed of twice of the differential case speed, but the other one is not rotating, at this time, the machine is at a standstill condition. This will seriously affect the productivity and function of LHD, therefore the POSI-TORQ differential (Fig.3) and NO-SPIN differential (Fig.4) with better functions are used in FAML-4 LHD instead of the common differential.
Fig. 3 Structure Scheme of POSI-TORQ Differential
1. Planet Bevel Gear 2. Outer Clutch Disc 3. Inner Clutch Disc 4. Side Bevel Gear
5. Spring Retainer 6. Disc Spring 7. Spider 8. Right Differential Case
9. Needle Roller 10. Fitting Flange of Brake Disc 11. Parking Brake Support
12. Left Differential Case
This figure shows that the structure of POSI-TORQ differential is almost the same as common one, the only difference is that a group of inner & outer clutch discs has been added on the big end of side bevel gear (item 4), and a group of disc springs and one disc spring retainer on the small end. Wherever the common differential is used the POSI-TORQ differential can also be used, and surely the function of POSI-TORQ differential is much better than the common one. Because of the common differential with:
M1 M2 = M0 (1) M2-M1=MF（2）
M0 – the torque comes from the differential case, which is the total torque input to the main driving.
MF – the friction torque in differential.
M1 – the torque comes from the wheel with less traction power.
M2 – the torque comes from the wheel with large traction power.
M1/ M2 = 0.555~0.56
If increase the friction torque MF in the differential, then,
M1 = (M0 - MF) / 2 M2 = (M0 MF) / 2
That is to say, when one wheel is losing traction on the slippery, wet or mud road, the inner friction torque MF will be increased, and the minimum MF will be used to brake the wheel with less traction, and most of the power will be transmitted to the wheel with large traction power, of which the traction power is five times of the less one. This will greatly increase the traction power of two wheels under the poor condition, and decrease the attrition of tires. The common differential will become POSI-TORQ differential if adding two sets of disc spring and clutch units to it, so that will increase the inner friction of differential and greatly improved the traction characteristic of LHD. That’s why we prefer POSI-TORQ differential to the common differential. Fig 4 is the Structure Scheme of NO-SPIN Differential.
Comparing NO-SPIN differential with the common one, we can find that they are completely different because, in this differential, thee is no planetary bevel gear but only two driven clutches, which are assembled with spider rotated by main transmission ring gear.
Fig. 4 Schematic Drawing of NO-SPIN Differential
1-Case Half Splined Hub 2-Spring Retainer 3-Spring 4-Driven Clutch
5-Silencing Ring 6-Holdout Ring 7-Spider Drive Ring 8-Centre Cam
The NO-SPIN differential allows the clutch and the middle spider being locked while the vehicle is moving forward or backward on the slippery ground. In this case, the NO-SPIN differential works as if the half shafts of both sides had been welded together and the speed of both wheels is same. If one wheel loses traction or leaves the ground, the opposite wheel, which still has traction, continues to drive the vehicle until the traction power is regained by both wheels. There can be no one – wheel spinout.
When making a turn, the driven clutch of the differential of outside wheel should run faster than the drive ring. Due to the large gap of jaw clutch of the drive ring and the tight meshing of the center cam and inner ring of the driven clutch, the inner gear ring of the driven ring has a relative sliding on the gear surface of center cam, in this case, the outside driven ring is moving axially and circumferentially by overcoming the power of spring until it is off the center cam. At the same time, the driven clutch is also moving axially and circumferentially and disengaging from the drive ring, so that make the driven clutch rotating faster than the differential case, then realizing difference during turning. Because the outside driven clutch is disengaged completely, the torque of drive ring will be fully transmitted to the slow-running wheel inside, that is:
M2≈M0
This is impossible to be achieved for either common differential or POSI-TORQ differential.
The tractive performance of POSI-TORQ differential is worse than that of NO-SPIN differential, but it can overcome the resultant impact load of NO-SPIN differential while being locked, besides there is a replaceable thrust shim for each planetary gear with good procedure and low maintenance cost. More important is that when one wheel is sliding, for NO SPIN differential, the other wheel should undertake 100% of torque, which requires the driving elements (wheel rim reducer) of wheels to have larger loading capacity, especially the front axle will take the max. load while in breaking condition which may be over the limit of driving elements. Therefore the POSI-TORO differential should be used for the front axle and the NO-SPIN differential for the rear axle which can put the advantages of the two kinds of differentials into full play. Now this kind of deposition has been adopted for LHD CY-4, as well as for some of the new LHD produced in foreign company, such as EJC Company, America Wagner Company, Schopf Company, but no in our company.
3 POSI-STOP brake is used for the brake system, which is spring applied, hydraulically released.
POSI-STOP brake is a new type of brake with the most advanced and safe, which is widely used for the LHD in foreign country in recent years. Although it has been developed and manufactured in our country already, but it is the first time to be used for the LHD. This brake is mounted on the inner sides of the four wheels. For its construction, see Fig.5 please.
When the LHD is started, the pressure oil gets into the brake through Hole A and pushes the piston and stopper to press the spring and release the friction discs then the LHD can be moved. If oil pipe is broken, and the oil pressure is reduced below the safe pressure, or the engine is at fault, the oil pressure is smaller than the spring force, the friction discs will be pressed by the stopper under the action of spring force, so as to brake the LHD.
No any oil, mud or dirt can enter into this brake because of its enclosed construction, of which the characteristics are as follows: long service life, more safety and reliability, less maintenance. Both park braking and emergency braking actions can be done by this brake without adding another park brake, in this way, the hydraulic system of brake is greatly simplified.