Contact Sealed Idler Rollers: Suitable for use in submerged conditions. According to the national standard "GB/T10595 Belt Conveyor," contact sealed idler rollers are referred to as waterproof rollers and are required to operate continuously for 24 hours in submerged conditions with a water ingress not exceeding 5g. This type of idler has a relatively high operating resistance.
In summary, contact seals have certain advantages in terms of sealing performance, but they typically result in greater operating resistance and frictional heat, and require regular maintenance.