MK Series - Mechanical speed variators

Product catalog summary

General Features
The K-MK series mechanical variators by SITI S.p.A. are designed for high starting torque, torque increase up to twice the nominal torque at minimum speed, uniform speed at low RPM, and high efficiency.

Design and Operation
The variator features inner and outer tracks, satellite wheels, and a handwheel for speed variation, allowing a speed ratio of 5:1. The differential variator includes a differential gear train for speed variation from 0 to maximum.

Operational Features
Variators maintain stability and efficiency across various speeds, focusing on high performance and reliability.

Manufacturing Features
Constructed with specific lubrication requirements and painting for durability, variators are enclosed on the front side and compatible with B5 and B14 motors.

Performance and Dimensions
Includes detailed performance tables and dimensions for various models, including compact flange series and combined motorized variators.

Accessories and Spare Parts
Offers accessories like gravitational indicators, remote controls, and position indicators, along with spare parts for variators and remote controls.

Important Notices
SITI S.p.A. reserves the right to modify technical features and accessories without notice. The catalogue content is protected and cannot be reproduced without authorization.

Specifications
The K-MK mechanical variable speed drive allows output speed regulation from 0 to maximum. Variator sizes range from MK2 to MK100, with specific temperature increase values during operation.

Running Temperature
Influenced by variator size, input/output speed, mounting position, ambient temperature, and gearbox type. Stabilizes after 200-300 hours of operation.

Operational Features
Torque is transmitted through friction surfaces with a maximum torque limit. Exceeding this limit can cause slippage, overheating, and wear. Efficient at maximum output speed, testing under maximum load conditions is crucial.

Lubrication
Achieved through oil showering, with oil replacement required after the initial 300 hours and every 3000 hours thereafter. Recommended lubricants include Shell, Agip, BP, Chevron, Esso, Fina, IP, and Mobil.

Recommendations
Temperature increases can exceed 25% during the running-in phase. Specific mounting positions and using a 2-pole motor can increase temperatures. Operate the handwheel only when the variator is running.

Lubrication Specifications
Lubrication is achieved through the rotation of gear parts in an oil bath. Initial oil change after 300 hours, subsequent changes every 3000 hours.

Mounting Positions
Attention to installation and operating position is crucial. Specific lubrication is required for many positions to ensure normal service life. Specify assembly position and control handwheel position when ordering.

Performance Tables
Includes detailed performance tables for the MK series motorized variators, listing specifications such as power, speed, torque, and pole configurations.

Catalog excerpts

MK Series - Mechanical speed variators-1

SPA SOCIET ITALIANA TRASMISSIONI INDUSTRIALI . >

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MK Series - Mechanical speed variators-3

SITI S.p.A. La ringrazia per la fiducia accordata e Le ricorda che il Suo riduttore il risultato di un lavoro di miglioramento del prodotto che i nostri tecnici perseguono continuamente, gra- zie ad una ricerca costante nel settore.La rete di Assistenza a Sua disposizione peraiutarLa a risolvere dubbi che potessero sorge- re nella lettura di questa pubblicazione.E訒 vietata la riproduzione, la memorizzazione olalterazione, anche parziale, di questa pubbli- cazione, senza una autorizzazione scritta da parte della SITI S.p.A. We, at SITI S.p.A., would like to thank you for the confidence shown in...

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MK Series - Mechanical speed variators-5

PREMESSAIl presente catalogo relativo ai INTRODUCTIONThis catalogue is related to the mechanicalvariators type K-MK, manufactured by SITI.DESIGN AND OPERATIONThe SITI variator consists of two inner tracks(1 and 2) which are pressed together onta the satellite wheels (7) by cup springs (3) this sub-assembly is mounted onta the input drive shaft (4). The number of satellite wheels (7) varies from three to six depending on the size of the variator. The outer tracks (5 and 6) also press on the satellite wheels (7), one track (5) is fixed to the main body, the other track (6) has limited rotational...

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MK Series - Mechanical speed variators-6

A differential variator is essentially identicalto the normal version already described. The only difference consists in the addition of a differential gear train. Rotation speed of the motor, or of the input shaft, is transmitted both to the variator train and to the differential sun wheel (a). The planet carrier (d) is shared by the variator and the differential unit so that it also drives the planet wheels of the differential (b). The transmission ratio of the differential is such that when the variator is running at minimum speed no rotation will be imparted to the dif- ferential annulus...

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MK Series - Mechanical speed variators-8

HANDWHEELThis is supplied with every standard varia-tor. A plastic disc is inserted in the handw- heel indicating in which direction to turn to increase and decrease output speed. VOLANTINO DI REGOLAZIONEE fornito a corredo del variatore standard. Alcentro Ҩ inserito, a pressione, un dischetto in plastica che riporta in rilievo lindicazione dei sensi di rotazione del volantino (e di conseguen- za della vite di comando) per ottenere lҒincre- mento o la diminuzione della velocita. HANDVERSTELLUNGHierbei handelt es sich um eine Standard-ausfuhrung des Verstellgetriebes, beste-hendaus einem Kunststoffhandrad,...

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MK Series - Mechanical speed variators-9

OPERATIONAL FEATURES OF THE MOTOR-IZED VARIATORThe planetary variator transmits a torquethrough friction surfaces. For each size, a max torque is fixed, and beyond said torque the equipment starts to slide, thus causing RPM losses, over- heatings, and as extreme problem wear, therefore a risk of adversely affecting the life- time of the variator.This arranges that the variator can take ad-vantage of the full motor power only in a range next to the max output speed. On the contrary at low speeds, considering that the output torque has to be limited due to friction reasons, the input power can...

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MK Series - Mechanical speed variators-11

Tipo Grandezza Poli Posizione di montaggio Type Size Poles Mounting position Output shaft Typ Grsse kW VoltDiam. alb. uscita Polig Hz Einbaulage Durch. der Antriebswelle > Tipo Grandezza Poli Type Size Poles Mounting position Typ Grsse ikWPosizione di montaggio Polig Volt Hz Einbaulage > Tipo Grandezza Poli Type Size Poles Mounting position Typ Gr涶sse ikWPosizione di montaggio Polig Volt Hz Einbaulage >

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MK Series - Mechanical speed variators-13

SEZIONI E CUSCINETTI SECTION DRAWING AND BEARINGS SCHNITTZEICHNUNG UND KUGELLAGER >

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MK Series - Mechanical speed variators-36

2 n > 2 M > 2 M > 2 TYPEpoles > 1 min > -1 min > -1 NmNm TYPpolig >

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MK Series - Mechanical speed variators-37

2 n > 2 M > 2 M > 2 TYPEpoles > 1 min > -1 min > -1 NmNm TYPpolig >

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MK Series - Mechanical speed variators-38

2 n > 2 M > 2 M > 2 TYPEpoles > 1 min > -1 min > -1 NmNm TYPpolig >

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MK Series - Mechanical speed variators-39

DIMENSIONI DIMENSIONS ABMESSUNGEN DIMENSIONI FORATURA DEL CORPO FIXING DIMENSIONS OF HOUSING GEHAEUSEBOHRUNGABMESSUNGEN >

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