Conveyor Blog

The decision to use a v-guide on a belt is a decision that needs to be understood so a good choice can be made. V-Guides in general will not solve all problems that are associated with belt mistrack. In general it is best to use a non v-guided belt in most applications when one considers cost, durability, and performance.

V-Guide Limitations

V-guided belts include single or multiple profiles on the underside of the belt to aid in the piloting of the belt. Belt manufacturers never recommend the v-guide be the primary source for piloting a belt. The v-guide should be used for temporarily restraining the belt during operation from intermittent side loads on the belt that will create a situation where the belt will mistrack.

With the understanding of the use of v-guides, it can be understood that a v-guided conveyor design when compared to a crowned pulley design should expect to exhibit:

• Lower belt life due to abrasion.
• Greater difficulties in tracking due to flat pulleys.
• Increased side to side belt movement due to the clearance required for the v-guide.
• The possibility of the belt being lifted off the frame due to external forces successfully pushing the v-guide out of it track and up on to the frame.
• Lower capability in terms of belt speed due to the abrasion of the v-guide.

Crowned Pulleys

Controlling of flat conveyor belts is most commonly achieved by utilizing trapezoidal (crowned) shaped pulleys. The crowned pulley utilizes an even distribution of opposing lateral forces to provide sufficient tracking power to guide a conveyor belt.

The key to comparing crowned pulleys to v-guided is to understand that crowned pulleys are free from rubbing or scraping of the v-guide itself. Alignment adjustments on each side of the conveyor permit control of belt to pulley alignment. These adjustments allow independent control of each side to bring these opposing lateral forces into balance for true center tracking.

The use of crowned pulleys normally requires that the conveyor be capable of sustaining pre-tension belt elongation values of approximately .2% to .3%. Tension values below this will result in insufficient lateral steering forces, as well as lower tension forces on the belt that drive friction and carry the load.

The key point to understand is a crowned pulley will provide continual pilot action without inducing damaging wear or abrasion to the conveyor belt.

V-Guide Uses

When the forces greater than the lateral forces created by the crown act on the conveyor belt, an additional source for piloting the belt is required. There are many methods for this, edge guides for durable edge belts, cam rollers attached to fabric belts, and the v-guide — the most commonly used.

V-guided conveyor applications do exist; some applications are as follows:

• Where pulley flanges can not be used or may interfere with products being conveyed
• Conveyors with long center distance where true tracking is critical.
• Side loading or unloading applications.
• Where the belt runs on its edge in a vertical position instead of lying flat on a conveyor surface.
• When reversing applications are required.

In some cases, v-guides must be used; the designer must choose wisely to assure the application is a good fit with all items noted above being considered.

Tags: Conveyor | Technical Tips

Managing conveyor life is both a comprehensive and important consideration from the day a system is conceived until the day it is retired from service. From a business perspective, maintenance is an essential activity for the achievement of optimal return on investment, as well as a key to remaining competitive in a hyper-competitive world.

Like maintenance for many other systems, the maintenance of conveyor systems divides into three broad categories: predictive, preventive, and corrective. The obvious advantage of predictive and preventive maintenance is that downtime surprises can be avoided, and when action needs to be taken, all of the parts, materials, and timing can be arranged for operational convenience.

To assure the highest performance for your conveyor system, QC Industries has combined a selection of high quality durable components and superior design criteria that support all aspects of conveyor operational effectiveness with the minimal amount of conveyor preventive maintenance.

Preventive maintenance, such as the cleaning of the conveyor, replacement of conveyor belt and bearings will be regimented by the type of environment the conveyor system is subjected to, the number of hours in operation, and the amount of performance demanded of the system.

Predictive measures, such as belt replacement schedules, periodic bearing lubrication intervals, and overall equipment inspection shall be determined by the environment the conveyor is subjected to, the number of hours in operation, and the production effects of measures taken at the corrective phase.

Maintenance, in general, affects all aspects of conveyor operational effectiveness and risks, not just system availability and cost — specifically safety, operational efficiency, energy efficiency, product quality, and environmental integrity.

For more specifics on maintaining your conveyor, see our Installation, Maintenance and Parts Manuals.

Tags: Conveyor | Technical Tips