Lagging is a phrase that refers to the application of a coating, cover, or wearing surface on pulley shells.

Lagging is frequently used to enhance the friction between the belt and the pulley or extend the shell’s life by providing a replacement wearing surface. For this reason, drive pulleys are frequently rubber lagged.

The layer of material attached to the shell of a conveyor pulley is known as pulley lagging. Its purpose is to protect the shell from damage, improve conveyor belt friction, and discharge water from the pulley.

Lagging is a phrase that refers to the application of a coating, cover, or wearing surface on pulley shells.

Each form of pulley lagging has its own variants and standards and is utilized for a number of applications.

what is pulley lagging

Pulley lagging improves belt-pulley traction, reducing load and wear on the drive, belt, pulleys, bearings, and take-up. In the shop or on the system, there is a lag. Proper pulley lagging is an essential component for efficient and cost-effective conveyor operation.

• Extends the life – of key conveyor components.
• Reduces wear – from abrasive materials.
• Prevents belt slippage – by increasing the coefficient of friction between the conveyor belt and the pulley.
• Creates a self-cleaning action – on the pulley surface and prevents the buildup of transported bulk material, water, snow or ice.

head pulley rubber lagging

Pulleys include multiple parts, including a shell, end disk, hub, shaft, and locking assembly. It’s possible that the end disk and hub are in good condition. On lower tension pulleys, the locking component can be replaced with a hub and bushing. In various regions of the world, the shell is also known as the rim. Head/Drive The conveyor’s discharge endpoint is where the pulley is positioned. It acts as the conveyor’s driving power. It frequently has a greater diameter than regular pulleys in order to maximize pulley life and traction. Pulleys with hot vulcanized rubber lagging, plain or grooved, can be supplied by the vulcan firm, as requested by the client. To improve tractive friction in unclean or damp situations, several grooving patterns, such as herringbone or diamond, might be given. Diamond grooves have the benefit of being able to be inserted in any direction, independent of the direction of the belt.

PULLEY LAGGING APPLICATION

Vulcanizing is the most common method of attaching lagging to the pulley (preferred in heavy-duty applications). Replaceable lagging is another option. The lagging strips are fastened to the face of the pulley using bolts or welds and may be simply changed in the field. Hundreds of tiny ceramic tiles are molded onto a strong rubber base to create ceramic pulley lagging. Ceramic lagging may greatly improve drive traction in some applications.

Types of Lagging

• Rubber lagging
• Ceramic lagging

The most frequent form of pulley lagging is rubber.

 It’s a’soft’ substance that provides high grip and is resistant to wear. Other features include pulley shell protection and enhanced conveyor belt friction.

CONSTRUCTION

Rubber lagging is frequently used to increase the friction between the belt and the pulley or to extend the life of the shell by providing a replacement wearing surface. For this reason, drive pulleys are frequently rubber lagging work.

Pulley Rubber Lagging is made from the best quality materials and adheres to the industry’s strictest quality requirements.

All pulleys are vulcanized in-house with our unique bonding method and state-of-the-art computer controlled autoclaves.

pulley rubber lagging procedure

Pulley Lagging for Conveyor Belts

To minimize early wear and strengthen the grip of tension pulleys, which lowers spillage, the pulley lagging is bonded directly to the pulley surface.

Unlike other linings, such as ceramic, vulcan rubber pulley lagging achieves the maximum coefficient of friction factor while causing the least amount of belt cover damage.

Vulcan’s patented pulley lagging also acts as a self-cleaning mechanism for the conveyor belting, extending the shell’s life. This specialized method avoids material caking, ensuring that alignment and performance are maintained.

When it comes to rubber lagging, there are several possibilities. Depending on your use, it can be grooved and curved to provide more flexibility. Rubber also has the advantage of being one of the most cost-effective varieties of pulley lagging. Rubber lagging may be used in a variety of applications. Different qualities, like as thickness and hardness, can be used to meet your goals depending on your application. Rubber lagging may be shaped and grooved into almost any form or pattern.

Rubber lagging has a limited operating life and must be replaced on a regular basis, which is one of its drawbacks. Even though rubber lagging enhances the conveyor belt’s friction, belt slippage might still occur.

Rubber lagging isn’t the best choice for achieving high amounts of friction on pulleys.

To enhance the friction between the pulley and the belt, rubber lagging is placed to the pulley shells.

Diamond grooved lagging is commonly used on conveyor drive pulleys, as seen in the illustration. The term ‘diamond grooved lagging’ refers to the lagging’s pattern, which, like automobile types, improves grip or friction even when the belt surface is unclean.

eramic lagging

Ceramic lagging is another typical form of pulley lagging. Because ceramic is more tough and lasting than rubber, it is employed. The two most common reasons for considering ceramic lagging are harsh environments and abrasive materials.

‘Smooth’ and ‘dimple’ ceramic lagging are the most popular varieties. Both of these items improve the belt’s friction, grip, and tracking, as well as eliminating or reducing belt slippage.

Because the enhanced fiction and grip aids in pushing the conveyor belt, drive pulleys are frequently lagged with dimple ceramic lagging. The amount of ceramic on the lagging’s surface may be customized based on your needs, and it’s utilized to increase or decrease friction and grip.

Depending on your demands and budget, it can also be utilized to boost wear resistance. Smooth ceramic lagging can be used to lag non-drive pulleys. Because ceramic lagging is more expensive than rubber lagging and is only used when absolutely essential, it is less prevalent than drive pulleys.

As a rubber-backed ceramic strip or sheet, ceramic lagging can be placed to the pulley shell. The pulley shell is attached to the rubber backing. The alternative option is to adhere the ceramic tiles directly to the pulley shell.

Ceramic lagging has a number of drawbacks. Ceramic is brittle and susceptible to cracking. The most common source of this problem is falling material or hard items stuck between the lagging and the belt. Furthermore, while choosing ceramic lagging, take into account conveyor design, transition lengths, and drive traction.

Specifications for Lagging

Rubber pulley lagging is often classified as follows in terms of kind, hardness, thickness, and finish:-

a) Lagging Finish and Type

The type of lagging to be used is determined by the above-mentioned application, duty, and necessary life of the lagging.

The table below shows the many types of lagging used on troughed belt conveyors in general:-

Pulley Location	Type of Lagging
	Diamond Grooved	Plain	No Lagging
Drive	X	X
Tail	X	X	X
Bend		X	X
Take-up	X	X
Snub		X	X

Strip lagging and ceramic-type lagging are not commonly used on troughed belt conveyor pulleys.

b) Lagging hardness

The pulley placement determines the hardness of the rubber lagging to be used on a conveyor.

Snub pulleys and bend pulleys, for example, need lagging with a hardness of 35 to 45 Shore ‘A’ when they come into touch with the filthy or carrying side of the belt.

Lagging with a Shore ‘A’ hardness of 55 to 65 should be used on the drive, take-up, and tail pulleys.

Lagging Thickness (c)

The thickness of rubber lagging varies greatly. The following are some of the most often utilized lagging thicknesses:

Grooved lagging, drive pulleys

10 to 12 mm

Plain lagging, other pulleys

6 to 10 mm

Pulley Lagging Care and Maintenance Recommendations

Rubber lagging, like any equipment, has a life expectancy that is determined by the operational environment, the quality and frequency of maintenance, and how the equipment is utilized.

a) Conveyor operation that is correct

Regardless of the above, the following simple recommendations can help you get the most life out of your pulley lagging:-

• To prevent belt slide on the driving pulley(s) at starting, make sure the conveyor’s take-up unit applies the necessary load to the belt.
• Throwing sand or other similar stuff into the pulley feed/nip point will not minimize belt slip. This causes the lagging to wear out faster.
• Over-filling the conveyor will require more torque to start and run the belt, which might cause the belt to slip over the driving pulley.
• Install and maintain a belt plough right ahead of the tail pulley on the return belt. This reduces the chance of lumpy material becoming stuck between the belt and the pulley, causing localized damage to the lagging and belt.
• Check that the pulleys are properly aligned so that the wear pattern is consistent across the pulley.
• Ensure that the take-up is accurately set in screw take-up units to provide enough belt tension under all operating situations.
• Prevent or rectify leakage onto the return belt so that the pulleys are as close to a clean belt as feasible.
• Install and maintain belt scrapers to prevent debris from accumulating on bend and snub pulleys.
• Consult the designer to clarify the conveyor design specifications and start-up philosophy if a drive pulley
• continues to slip on starting for no apparent reason. Do not forget the slipping!

b) Proper component and design choices

• To avoid over-stretching of the belt and lagging, the designer should choose the appropriate pulley diameter.
• Depending on whether the pulley is a driving, tail, or take-up pulley, choose the proper type and hardness of lagging.
• Use grooved lagging on drive pulleys to help with traction, moisture removal, and slipping when dirt becomes stuck on the return belt.
• When constructing a conveyor, stick to standard conveyor design techniques and equipment sizing requirements.

c) Preventative measures

• Regularly inspect and monitor the condition of the pulley lagging.
• Repair lagging that has been damaged locally before it spreads to other locations.
• To extend the life of the lagging, make sure it is re-lagging of pulleys is done by skilled employees.
• Make a spare pulley accessible so that a broken pulley or lagging may be taken out of operation and properly repaired or refurbished in a controlled environment.
• pulley rubber lagging procedure

Pulley Lagging for Conveyor Belts

To minimize early wear and strengthen the grip of tension pulleys, which lowers spillage, the pulley lagging is bonded directly to the pulley surface.

Unlike other linings, such as ceramic, vulcan rubber pulley lagging achieves the maximum coefficient of friction factor while causing the least amount of belt cover damage.

Vulcan’s patented pulley lagging also acts as a self-cleaning mechanism for the conveyor belting, extending the shell’s life. This specialized method avoids material caking, ensuring that alignment and performance are maintained.

rubber lagging on pulleys

When it comes to pulley lagging, there is a huge variety of goods and specifications to choose from. This is to represent the wide range of circumstances encountered in mining operations across the world.

Having the proper lagging on your pulley ensures that it runs smoothly and lasts for a long time. Before you choose your next pulley lagging, there are four things you should know.

Operating Conditions

Mining activities take place in a variety of environments, from the frigid plains to the scorching deserts.

When deciding which pulley lagging to use, factors such as operating temperature, wet or dry environments, and chemical interaction all play a role in the selection.

. Abrasiveness of Material Being Processed/Transported

Sand Product abrasion is a crucial issue when deciding the sort of lagging material to employ.

Iron ore’s characteristics may be rather abrasive. Aluminium borate, on the other hand, is as soft as powder. Pulley lagging specs for these two items would be different.

The abrasiveness of the material on the belt must be considered while choosing the optimum type of pulley lagging. This is owing to the fact that various materials require varied belting requirements.

 Belt Type and Belt Running Speed

When it comes to pulley lagging, the belt type and operating speed are critical considerations.

The lagging should always come second to the belt in terms of importance. When compared to lagging, belts are relatively expensive to replace. As a result, if one of them were to fail first, the pulley lagging would be the most cost-effective option.

Rubber conveyor belting comes in a variety of hardness, elasticity, and abrasion resistance ratings.

The pulley, lagging, and belt should all operate smoothly when building a conveyor. When one of the components is changed, you must think about the other components and how they are affected. The pulley, lagging, and belt should all operate smoothly when building a conveyor.

Does Your Conveyor Pulley Need Refurbishing?

Conveyor pulleys are vital components of a conveyor system because they are heavy-duty and operate continuously. Conveyor pulleys, although being built to last, will experience normal wear and tear after many years of continuous usage. They can, however, be damaged and require replacement if they are not properly maintained. This firm advises that conveyor equipment should be maintained on a regular basis to reduce wear and extend service life. This includes restoring or reconditioning pulleys, which will extend the life of your pulley and save you money over replacing it entirely.

Visibly Worn Lagging​

A worn-down lagging is a strong indication that a refurbishment is required.

The first line of defense against wear on a pulley is lagging. The pulley will be subject to abrasive damage if the lagging wears out (which is to be expected over time). If the lagging has worn down to the point where the pulley shell is visible, the pulley must be refurbished with new lagging immediately, as damage to the pulley shell may already have occurred.

Lagging That Has Come Loose

The bonding glue has degraded if the lagging has come free from the pulley and is flapping around. As previously stated, maintaining excellent lagging is critical to extending the life of your pulley. To avoid further damage to the pulley and the belt, any lagging that has come loose must be restored.

Seized Bearing​

The rotation of the pulley will be disrupted by seized bearings (due to a number of circumstances). This can cause a slew of problems for your entire conveyor system. Lack of lubrication, old age and fatigue, product build-up, and other factors can cause seized bearings.

Strange Noises

Strange noises emanating from your pulley might also indicate that it needs to be refurbished (or replacing). The remedy will be determined after a safe and thorough assessment of the source of the noise. Lagging that has come loose, or bearings that have cracked or seized, will almost certainly generate a noise, alerting you to a pulley that needs to be repaired.

Extreme Rusting or Corrosion of Elements​

Your pulley housings and bearings will rust or corrode over time. While little rusting or fading isn’t usually a cause for alarm, severely worn pulley components may indicate the need for replacement. Heavily worn bearings and housings can cause breakdowns.