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SIT V-belts drives catalogue - intro

  1. V-pulleys catalogue (EN)
  2. V-Belts SIT Drives (EN)

Power transmission is key part of an automatic machine, in terms of efficiency, reliability and durability. Only using quality components can such goals be obtained.
SIT S.p.A. belt drives, thanks to the innovative construction features, the respect of the international standards and continuous deve- lopment, are the ideal, versatile and economic solution for machine design and manufacturing.
SIT, has been producing power transmission solutions for over five decades, and can offer one of the widest range of products in the market that will permit you to find the most efficient and compact solution at the best quality/price ratio.

When synchronization is not required, V-belts make an excellent cost effective, quiet and efficient means of transmitting power. However not all V-belts perform the same. Depending on your application and your objectives, some V-belts will be better at getting you closer to your end goal.
The resources of research and development which back a SIT belt are also supported by a philosophy of marketing which aims to give the customer the right belt for the drive. Apart from the benefits of:
• high power capacity belts
• reliable performance
• consistent quality
• economic benefits
Attention to details such as standardisation give further evidence of the SIT commitment to its customer.
As a result SIT can claim that its V and Wedge belts are compatible with appropriate standards published by ISO, RMA, BSI, DIN, AFNOR and others.

SIT has carried on a great deal of research, in all belting with the viewpoint of the user of the system (belt and pulleys) in mind, and for that reason has not confined the work to the testing of one or two particular aspects of the problem. The user obviously desires a drive that will carry the load with the least possible attention, and one that will operate satisfactorily for a long enough period to give the lowest possible cost per unit of service. We have observed that the action of a belt under actual service conditions is the only means of measuring its value. We, therefore, built testing machines upon which belts could be run for long periods, under conditions exactly as in service, with the additional equipment necessary to measure the speed, slip, tensions, power, etc. We find that one of the vital factors, in satisfactory belt service, is freedom from frequent adjustment of tension. One of our standard tests, therefore, determines how long a belt will run without take-up adjustment. These actual service tests are supplemented by dynamometer tests and also by a large number of tests of the ability of belts to withstand flexing over various sizes of pulleys, and under various tensions and speed conditions.

Classical V-Belts
Are the most widely used V-Belts. Used more out of habit and convenience than design, these belts can transmit power at the lowest installation cost. However they occupy more space and the drives weigh more than Narrow V-Belts drive. Also, Classical V-Belts are usually less efficient than Narrow V-Belts. But their versatility and wide range of sizes and types make them an attractive option.

Narrow V-Belts
Narrow V-Belts cross section offer higher power capacity for any pulley size. This allow the use of smaller belts or fewer belts to transmit the load, an important advantage if your target is to maximize power transmission efficiency by reducing drive weight and size.

Raw-Edge V-Belt Construction vs. Envelope Construction
Unlike conventional fabric covered V-Belts, raw edge belts have no cover. Raw-edge V belts, thanks to the higher coefficient of friction, have higher load capacity and efficiency. Cogs, on the inner surface of the belts, increase air flow to enhance cooler running. They also increase flexibility allowing the belts to operate with smaller pulley than traditional envelope (wrapped) belts.
SIT has a complete offering of cogged, raw-edge belts in narrow and classical type.

Each family of belts will be characterized by the Performance Index. This index is a fast and intuitive visual parameter to understand the performance level of the belts family. Complete technical information about belts performance are include in the Power Rating table.

Precision Matched System
Controlling the elongation is the key to matchless performance. Since all materials will elongate in performance, the secret to reliable matchless performance isn’t to eliminate elongation, but to control it so it is minimal, predictable and uniform.
SIT V-belts respect the Precision Matched that, thanks to the control and the strict respect of the length tolerance, permit an installation of a set of V-Belts on the same drive avoiding any matching problem.
Tolerances obtained by the Precision Matched are tighter compared to what is prescribed by the ISO 4184.