• 1.1 gear reducer overall dimensions are suitable to be equipped with large motor sizes transmitting high nominal and maximum torques, supporting high loads on low and high speed shaft ends;
• 1.2 low speed shaft design: cylindrical shaft end with 1 key and 1 butt-end threaded hole (size≤ 353) or 2 keys and 3 butt-end threaded holes (size≥354), splined shaft ends with spigot recess and 3 threaded holes, hollow shaft with shrink disc (for shaft mounting), splined hollow shaft;
• 1.3  improved and up-graded modular construction both for component parts and assembled product;
• 1.4 gear reducers: input face with hub or flange and with holes; cylindrical high speed shaft end with key;
• 1.5 gearmotors: motor standardized to IEC directly keyed into hollow high speed shaft;
• 1.6 low speed shaft bearings:
        200~280------double taper rollers
        353~695------adjustable-cylindrical roller and ball  bearings.
• 1.7 nodular cast iron casing (excluding the steel gear) with thick walls  and stiffening ribs;
• 1.8 shafts made from casehardened and hardened steel; 
• 1.9 oil bath lubrication; synthetic or mineral oil with filler plug; with valve, drain and level plug; sealed;
   

2.Train of gears

• 2.1 with1, 2, 3, 4 planetary gears (coaxial type);
• 2.2 with 1 bevel gear and 1, 2, 3 planetary gears (right-angle type);
• 2.3 nominal transmission ratios to R40/3 (3.15~ 3 000) for coaxial type reducer, R40/3 (10~2 120) for right angle type reducer;
• 2.4 case hardened and hardened gear pairs: external gearings made from 20CrMnTi, internal gearings made from 42CrMo;
• 2.5 cylindrical spur gears with profile and flank modification, ground or accurately shaved;
• 2.6 GLEASON spiral bevel gear pairs with ground or accurately lapped profile;
• 2.7 floating planet carrier in hardened and tempered steel;
• 2.8 concordant directions of rotation of high and low speed shaft, both for coaxial and for right angle types;
• 2.9 gears load capacity calculated for tooth bending strength and pitting; maximum instantaneous power verified.

3. Electric Motor

• 3.1Standard design
• 3.11 motor standardized to IEC;
• 3.12 asynchronous three-phase, totally-enclosed, externally ventilated,with cage rotor;
• 3.13 single polarity, frequency 50 Hz,  voltage 220 V /380 V +/-10%,up to size 132 , 
•         380 V/660V +/-10% from size 160  upwards;
• 3.14 protection degree IP54, insulation class F;
• 3.15 rated power delivered on continuous duty (S1) and at standard voltage and frequency; maximum ambient  temperature 40 ℃, max altitude 1 000 m;
• 3.16 capacity to withstand one or more overloads up to 1,6 times the nominal load for a maximum total period of 2 min per single hour;
• 3.17 starting torque with direct on-line start at least 1,6 times the nominal one (it is usually higher);
• 3.2 Brake motor
• 3.21 motor standardized IEC having the same parameters as normal motor;
• 3.22 particularly strong construction to withstand braking stresses; maximum reduction of noise level;
• 3.23 spring-loaded DC electromagnetic brake; feeding from the terminal box; brake can also be fed independently direct from the line;
• 3.24 braking torque proportioned to motor torque and adjustable by adding or removing spring pairs;
• 3.25 high frequency of starting enabled;
• 3.26 rapid precise stopping;
• 3.27 break motor supplied without hand lever. If need hand lever, please indicate. 
• 3.28 hand lever for manual release with automatic return;  removable lever rod. 
• 3.29 For other specifications and details see specific literature.
• 3.3 Suitable for installing inverter
• 3.31 for normal motor, permissible frequancy range is: 20Hz~60Hz;
• 3.32 for brake motor, the wire should be independent from the terminal box when being used together with inventer;
• 3.33 for the motor designed for inventor, see specific literature for permissible frequancy and other specifications.
   

4. Input Speed

• Permissible input speed

Real input speed must less than or equal to the specified permissible input speed, if higher, please contact SGR company.

5. Thermal Power P_t

• Nominal thermal power P_tN, indicated  in the table, can be applied in following working condition: operating on continuous duty, maximum ambient temperature of 40 ℃, max altitude 1 000 m and wind speed 1,25 m/s, approximately oil temperature lower than 80 ℃ .

• thermal power P_t can be different from the nominal P_tN as described above, as per following formula:   P_t = P_tN * f_t
• where f_t is the thermal factor which is caculated by formula:     ft=K_p * K_s 
        K_p---ambient temperature and type of duty  factor, listed in following table.
        K_s---mounting position and input speed  factor, listed in following table.
• 
•  It is always necessary to verify that the applied power P₁ is lower or equal to the P_t value
  P₁≤(P_t = P_tN * f_t)
• Whenever the thermal verification should not be satisfied, it is necessary to install an independent cooling unit, made up by oil/air or oil/water heat exchanger; 
• Thermal power needs not be taken into account when maximum duration of continuous running time is 0,5~1,5 h (from small to large gear reducer sizes ) followed by rest periods long enough to restore the gear reducer to near ambient temperature (likewise1~3 h).
• In case of maximum ambient temperature is above 40℃ or below 0 ℃, please contact SGR company.

6. Service Factor

• Service factor f_s takes into account by considering different running conditions (nature of load, running time, frequency of starting, other considerations) which must be referred to when performing calculations of gear reducer selection and verification.
• The powers and torques shown in the catalogue are nominal (i.e. valid for f_s = 1) for gear reducers, corresponding to the f_s indicated for gearmotors.
•  f_s perform  formula:  f_s= f_t * f_f

• the nature of load is according  to the application.
• maximum time on overload 15s / on starting 3s; if over and/or subject to heavy shock effect, please contact us;
• a whole number of overload cycles (or start) imprecisely completed in 1, 2, 3 or 4 revolutions at low speed shaft, if precisely continuous overloads should be assumed;
• if higher reliability is required (particularly under tough conditions for maintenance,  importat position of gear reducer in production, personnel safety, etc.), multiply f_s by 1.25~ 1.4

7. Select suitable gearmotor or gear unit

• a. caculate all necessary data: required output power P₂ of gear reducer, output speeds n₂ and input speed n₁, running conditions (nature ofload, running time, frequency of starting and any other considerations)
• b. determine service factor f_s on the basis of running conditions
• c. select the size of gear reducer ( train of gears and transmission ratio at the same time) on the basis of n₂, n₁ and of   power P_N2 (higher than or equal to P₂ * f_s )
• d. calculate power P₁ required at input side of gear reducer using the formula P₂/η (η is  the  transmission efficiency of the gear reducer )
• e. transmission efficiency
• gear reducer with 1 planetary gears (1E): 97 %
• gear reducer with 2 planetary gears (2E): 94%
• gear reducer with 3 planetary gears (3E) : 91%
• gear reducer with 4 planetary gears (4E): 89 %
• with 1 bevel gear pair and 1 planetary gear (CE): 95%
• with 1 bevel gear pair and 2 planetary gears (C2E): 92 %
• with 1 bevel gear pair and 3 planetary gears (C3E): 90%