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CMI-I Series - Combined wormgearboxes

CMI-I Series - Combined wormgearboxes
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CMI-I Series - Combined wormgearboxes

Product catalog summary
General Features
This document covers the single worm gearboxes with primary reduction series I-MI and combined worm gearboxes by SITI S.p.A. The I-MI series includes 12 sizes with power applications from 0.09 to 18.5 kW. Housings are made of die-cast aluminum up to size I 80, and painted cast iron for larger sizes. Gear ratios range from 7.5 to 100.
Design Features
  • Toothing Profiles: The "ZI" type profiles ensure smooth, silent, and vibration-free operation.
  • Aluminum Pressure Die Casted Housings: Provide strength, stiffness, and effective heat exchange without the need for painting.
  • Painting: Aluminum housings are unpainted, while cast iron housings are painted.
Reversibility and Irreversibility
Reversibility is influenced by efficiency, helix angle, machining precision, surface finish, and sliding speed. Irreversibility occurs when the gearbox cannot be driven from the slow shaft under certain conditions.
Technical Data and Performance
Includes technical data tables, lubrication guidelines, and performance data for various configurations and motor types. Covers mounting positions, dimensions, and allowable external loads.
Accessories and Spare Parts
Lists available accessories like torque limiters, shaft configurations, and torque arms, along with spare parts for maintenance.
Introduction
Focuses on the I-MI series from I 40 to I 90, highlighting efficiency improvements due to new toothing profiles and synthetic oil lubrication.
Specifications
Features "ZI" involute toothing profiles for enhanced efficiency. Taper roller bearings improve resistance to loads. Output flanges allow for universal or modular assembly.
Static and Dynamic Irreversibility
Static irreversibility occurs when static efficiency is less than 0.4 to 0.5. Dynamic irreversibility occurs when dynamic efficiency is less than 0.5.
Recommendations
For complete irreversibility, use brake motors to prevent reverse motion, especially in safety-critical applications.
Conclusion
Provides guidelines for selecting appropriate gearbox configurations based on application requirements.
Specifications
Wormgearboxes are designed for higher static and dynamic loads. A table indicates maximum static load based on reduction ratio. Exceeding recommended loads can compromise structural integrity.
Procedures
Use motors with slightly lower input power than catalog specifications to prevent exceeding dynamic load capacity during start-up.
Standards and Recommendations
Ensure actual loads do not exceed maximum dynamic load, especially for ratios higher than 40:1. Select motors based on maximum output torque with a service factor not lower than 0.8.
Features
New primary reduction gears are made of die-cast aluminum with B14 type flanges, minimizing space. They can be supplied as kits for direct installation.
Lubrication
Primary reduction units with motors are pre-filled with oil. Others require synthetic oil ISO VG 320.
Performance Tables
Divided into versions with and without motors, providing data for various input speeds and dynamic efficiencies. Advise on selecting motors based on maximum output torque.
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Catalog excerpts

CMI-I Series - Combined wormgearboxes-1

SPA SOCIET ITALIANA TRASMISSIONI INDUSTRIALI . >

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CMI-I Series - Combined wormgearboxes-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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CMI-I Series - Combined wormgearboxes-5

DESIGN FEATURES1 - TOOTHING PROFILESMating profiles of bronze wormwheel andworm screw are of type ZIӔ (profile with in- volute section).This gives rise to a gradual, constant andshockless matching in the rolling of mating profile throught all the possible running con- dition. Wormgearbox running is much more silent and free of vibrations. This type also relates to sizes I 90 and I 110.2 - ALUMINIUM PRESSURE DIE CASTEDHOUSUNGSThe use of pressure die casted aluminiumhousings of very modern design has been introduced(up to the size I 80 included). The excellent surface finishing makes paint- ing...

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CMI-I Series - Combined wormgearboxes-7

Among all these factors, the efficiency of thetoothing profiles proves to be the most mean- ingful one in affecting successfully the whole efficiency of the gearbox, and it is on a large extent tied to the helix angle of profiles. Large helix angles involve the highest de- grees of efficiency, thus irreversibility is lower, while smaller and smaller helix angles involve higher and higher efficiency, which a greater and greater degree of irreversibil- ity comes from. In oder to get the fittest solution ofr a cer- tain application, requesting more or less re- markable features of irreversibility,...

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CMI-I Series - Combined wormgearboxes-8

The opposite condition, i.e. the dynamic ir-reversibility takes place when RD > 0.5 Among the more effecting factors on the dy- namic efficiency there are to mention the same rotational speed (i.e., as higher the Speed, as higher dynamic efficiency too), and the more or less continuous load vibrations. The following scheme proposes an analysis of the different degrees of irreversibility as a function of the helix angle. Of course, these are only indicative data, since several other factors tied to the application come into play,providing to change the situation more orless drastically:higher...

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CMI-I Series - Combined wormgearboxes-9

TABELLA DATI TECNICINella tabella sono riportati i parametri caratteri-stici dei riduttori a vite senza fine. Vengono rappresentati in ordine: a)il numero di principi della vite ( TECHNICAL DATA TABLEThe table here below gives the typical pa-rameters of worm/wormwheel pairs. The following data are given one after the other:a)the number of starts of the worm ( TABELLE DER TECHNISCHEN DATENIn der Tabelle sind die Kenngren der Schnek-kengetriebe angegeben.Diese sind wie folgt unterteilt: > Z 1 ) dal qualesi desume il numero di denti della corona ( a )Windungen der Schnecke (z > 1 ), aus denendie...

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CMI-I Series - Combined wormgearboxes-10

LUBRICATIONAll the wormgearboxes series I-MI up to sizeI 90 included are supplied already pre-lubri- cated by SITI, and are missing the oil plugs, since the lubricant used is lifetimeӔ, in other words it does not require any maintenance during the wormgearboxes life. Synthetic oil is used. SITI fills- in the wormgearboxes up to I 90 with the synthetic oil SHELL TIVELA SC 320. On the contrary, the larger wormgearboxes (I-MI 110/130/150/175) are supplied without lubricant and with plugs for loading, dis- charging and checking level of the oil. In these cases, filling-in the gearboxes is committed...

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CMI-I Series - Combined wormgearboxes-11

Riempimento riduttori I - MI 1 10 175 Filling wormgearboxs I - MI 1 10 175 Bef緼llen der Getriebe I - MI 1 10 175 Il riempimento dei riduttori affidato al cliente, che potr稠 utilizzare il lubrificante a base sinteti- ca.LUBRIFICANTI CONSIGLIATIOLI SINTETICILubrificazione a vita The client must fill the gearboxes with syn- thetic oil.RECOMMENDED LUBRICANTSSYNTHETIC OILLifetime lubrication Das Auffllen der Getriebe ist dem Kunden ber-lassen, der Schmier켶l auf Synthetikbasis ver-wenden kann.EMPFOHLENE SCHMIERMITTELSYNTETIK ֖LELebensdauerschmierung MARCA / MAKE / HERSTELLER TIPO DI OLIO / TYPE OF...

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CMI-I Series - Combined wormgearboxes-12

PESO DEI RIDUTTORI WORMGEARBOXES WEIGHT GEWICHT DER UNTERSETZUNGSGETRIEBE NOTECombined gearboxes weight is the sum of weights of the two units. NOTAIl peso dei riduttori combinati la somma dei pesi delle due unit. HINWEISDas Gewicht der kombinierten Getriebe ist dieSumme der Gewichte der beiden Einheiten. >

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CMI-I Series - Combined wormgearboxes-13

Tipo Grandezza alb. lento o cannotto (mm) Versione Pos. di mont. Altre indicaz. Type Size output or hollow shaft Version Mount. pos. Other indicat. Typ Gr踶sse > PAM abtriebwelle oder Bchse Ausf輼hrung Einbaulage Weitere Angaben > Grandezza Poli Forma costruttiva Protezione Classe di isolamento Altre indicaz. Size Tension / frequency Poles Type Protection Insulation class Other indicat. Grsse kWTensione / frequenza Spannung / frequenz Polzahlen Bauform Schutzart Isolation sklasse Weitere Angaben >

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CMI-I Series - Combined wormgearboxes-15

HOW TO READ THE PERFORMANCE TA-BLESThe tables of performance of singlewormgearboxes, have been windened, in order to make them suitable to an easy read- ing, even in case of special applications, or applications out of the standard.First of all, a differentiation has been cariedout between the performance of gearboxes without motor and gearboxes complete with motor.In case of gearboxes complete with motor, ithas been taken account of the possible PAM- arrangements of each gearbox size and each ratio, and the max. input power allowed at each input speed n IMPOSTAZIONE E LETTURA DELLE TABEL-LE...

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CMI-I Series - Combined wormgearboxes-16

In fact, when input speed is as high as 2800RPM, a few potential problems, like the tem- perature achieved inside the gearbox, start of vibrations or noise, trend to grow.As a general rule, we recommend the use ofwormgearboxes at 2800 RPM input speeds (2 poles motors) only in applications having a relatively low service factor (1.25 max.)and a very low degree of intermittency.The use of n Quando la velocit di ingresso pari a 2800 giri/min, accennano a esaltarsi alcuni problemi, come la temperatura raggiunta all਒interno del riduttore in condizioni operative e la tendenza allinnesco di vibrazioni...

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