Gearbox for EOT Cranes
In a general sense, a gearbox contains a mechanical unit or a component comprising a series of integrated gears within a one housing. Basically, a gearbox functions similarly as any system of gears works; it alters the torque (rotational force) and subsequently the speed between a driving mechanism like a motor and load.
In every manufacturing houses, gearboxes efficiency and reliability play a major role in the productivity of the overall plant operation. Gearboxes performance and reliability are the key factors in increasing operational efficiency, minimize downtime subsequently increasing production and profitability. It is best to call a specialist whenever any repair or refurbishment is required. It is always recommended to keep previously determined dimensions of gearboxes and its components for future needs (for repair and refurbishment) in order to quickly determine what dimensions was fit for that particular part as some components would not retain their original shape, once they have been used.
What are Gearboxes?
Gearboxes are the mechanical devices which allow vehicles to operate at different speeds within the capacity of the engine that is controlled by the operator or driver. Gearboxes are available in a different range of load capacities and speed ratios, mainly with the purpose of increasing and reducing speed. It is a fully integrated mechanical component comprising a series of gears in housing with shaft and bearings (to support and maintain loads) and a flange of motor mounting in many cases.
These are used for any machinery or equipment that have speed requirements and changes to torque. There are several manufacturing firms which indulge in producing helical gear boxes which operate on modular Concept of construction in compliance with standards with respect to sizes, dimensions.
What do we offer?
AMT International is a trusted Crane Duty helical gearbox manufacturers in India who merge the latest production technology with the high quality material to produce highly durable and reliable solutions. We make helical gear boxes built on modular concepts of constructions to remain compatible to the standards with respect to size and dimensions. Merger of the latest technology in production helps in economic mass production, comprehensive stock maintenance, timely deliveries and easy services.
TYPES OF CRANEDUTY HELICAL GEARBOXES:
Horizontal Single Stage Type HA Gearbox
Horizontal Double Stage Type HB Gearbox
Horizontal Triple Stage Type HC Gearbox
What do we offer?
It is primarily a function of reduction stages and type of gearing, mainly when loaded to the rated capacity, affect the efficiency of the gearbox:
|Type and reduction Ratio||Efficiency||Centre distance||Reduction Ratio|
|Horizontally signal stage||98%||100-400 mm||1.83:1 to 8:1|
|Horizontally double stage||96%||250-1000 mm||8.23:1 to 48.57:1|
|Horizontally triple stage||94%||400-1250 mm||31.5:1 to 160:1|
|Vertically triple stage||93%||250-600 mm||14.85:1 to 33.4:1|
STANDARD INFORMATION AND GENERAL SPECIFICATIONS:
Housing are the protective cases for gears to spin. They are meant to provide a strong structure, support and protection to gears. We aim to manufacture housing with good quality casting iron along with Torsion resistant housing so that the vibration due to spinning can be reduced and it can also absorb the effect and heat produced by the engine. We manufacture housing as per the client’s requirement, in all ranges of capacity. We provide solutions matching their industrial requirements and get a new one fabricated that fit their needs.
GEARS AND PINIONS
We always use the finest quality raw materials to manufacture gears and pinions in accordance with the industrial requirements of the clients so that they can be sure of the functional efficiency of our products. The material mainly used in the manufacturing of pinions and gear wheel is made up of hard wearing special steel of graded quality which allow individual load conditions. Speed, ratio and load requirements are kept in mind while selecting raw material for module and foot prints that allow maximum tooth contact and overlap to ensure smooth functioning, without any noise.
Shaft pinions which are the integral component used in the manufacturing of gearboxes are made of heat treated alloy steel bars or alloy steel forging which are corrosion resisting and highly durable. Besides this, all other shafts are manufactured using heat-treated carbon steel to facilitate high precision tolerance by grinding. In addition to the standard shafts, we do manufacture customized shafts in any material or length to meet your application needs.
The success rate of any gearboxes depends on the quality of bearings it consists of. Good quality of anti-friction ample size bearing ensures that a gearbox would have a long serviceable life. These bearings are used to ensure high efficiency, sufficient centre distance and finest shaft alignment. Best quality seals are used in shaft extensions to prevent oil leakage and dust entering in it.
Depending upon application, standard gear units are cooled by dissipating normal heat through convection from the external surface. The housing is provided with additional cooling fans and lower housing cooling to ensure that the heat generated within the gears are absorbed and spreaded across the housing, over a sufficiently larger area. These cooling techniques ensure the higher performance of the gearbox.
In Helical gearboxes, Oil splash lubrication is used oftenly which is also referred to as an oil bath. In this method, it uses a reservoir which is filled with oil. When gears rotate, they get dipped into this oil reservoir and also splash oil on other gears and bearings which help to maintain the normal speed and smooth functioning overall. There is an oil level indicator provided in the housing which indicates that housing has required a certain amount of lubricant
Types of oil for crane gearbox:
For lubrication, it is recommended to use straight mineral oil or Forced oil/ Extreme pressure (E.P.) Oil meeting below mentioned specifications:
- Lubrication oil used in gearboxes must be high graded well refined petroleum Oil, falling between recommended viscosity range as recommended below:
Ambient temperature -10 to +150C 0 to 300C +10 to +500C ISO VG 100 ISO VG 220 ISO VG 320
- Viscosity of oil must be neutral and no grfit or abrasives should be present.
Recommendations for Oil Change:
- First oil change is recommended after 1000 hrs. of operation or two months whichever comes earlier. Subsequent oil changes should be made after every 2000 hrs or after six months whichever comes earlier.
- The operating temperature should not be excessive beyond 90ÂºC. Temperature below this is harmless for any component
Recommended lubricants for gearboxes:
|MAKER'S NAME||R. P. M OF HIGH SPEED SHAFT|
|WITHOUT OIL PUMP||WITH OIL PUMP|
|Up to 1500||Up to 1500||Above 1500|
|INDIAN OIL||Servomesh SP/EE 320||Servomesh SP/EE 220||Servomesh SP/EE 150|
|CASTROL||Alpha SP/EE 320||Alpha SP/EE 220||Alpha SP/EE 150|
|BHARAT PETROLEUM||Bharat Amocam 320||Bharat Amocam 220||Bharat Amocam 150|
|HINDUSTAN PERTOLEUM||Parthan EP 320||Parthan EP 220||Parthan EP 150|
|BALMER LAWRIE||Balmerol Gear Flux BM 320||Balmerol Gear Flux BM 220||Balmerol Gear Flux BM 150|
SELECT A GEARBOX THAT COULD PERFORM BETTER:
Correct selection is required if you want to achieve satisfactory performance from the gearbox.
- Determine the Class of duty of the cranes first to select gear units.
- For Hoist and Long Travel drive, it is recommended to use Single, Double and Triple stage Horizontal gear units type HA, HB and HC.
- For cross travel drives of the EOT cranes, triple stage vertical type VC is recommended.
- Assembly arrangement must be specified while ordering the gear units.
- Find out the required HorsePower for the prime-mover
- Calculate the required reduction ratio by dividing Input R. P.M. with output R.P.M.
- To keep the required ratio and size of gearbox minimum and small, try to reduce Input R.P.M.
- Select the gearbox size in a way that the required horsepower is equal or more than the consumed horsepower.
BELOW ARE SOME ASSEMBLY ARRANGEMENTS AVAILABLE FOR GEAR UNITS:
GEARBOXES AND DIMENSIONS DETAILS:
Single Stage Horizontal Type “HA”:
Double Stage Horizontal Type “HB”:
PINION GEAR ARRANGEMENT – Pinions are basically gears with small number of teeth which are designed to mesh with teeth on the gear rack. Pinions mounted to the steering shaft meshed with a steering rack to convert rotary motion into linear motion. There are many industrial applications where in the gear rack remains stationary and the pinion traverses. While in some arrangements, pinion rotates on a fixed axis and the gear rack moves. The later one is generally used in lifting or lowering applications. Racks and Pinions are used together to lift mechanisms like vertical movements, horizontal movements and allow the synchronous rotation of several shafts in general industrial machineries.