Commonly used non-contact seal gap seal, oil slinger seal and labyrinth seal, and other forms. Due to there is gap, in addition to the oil slinger seal, non-contact sealing grease for more occasions. To improve the reliability of seals, all kinds of seal can be used together.
Because of the sealing gap of the non-contact sealing device, in addition to the existence of internal friction of lubricant, won't appear any other friction, therefore, won't produce wear non-contact seal, use for a long time also won't produce significant temperature rise, can be used in high speed. But seal clearance cannot too much, otherwise the sealing effect is poor.
Non-contact sealed Structure Of NTN 6004-RZ Bearing http://www.fagbearings-hk.com/newproduct/NTN-6004-RZ-bearings-42004.html bearing parts:
1. Gap seal: simple structure, can satisfy the general conditions of sealing requirements. The choice of clearance e d 50 mm or less, e = 0.25 ~ 0.40 mm; D > 50 mm, e = 0.25 ~ 0.6 mm.
2. Grooved seal: groove filling grease inside make dust into hard, after a ring groove and spiral groove in two forms. Ring groove will typically have three. Groove width b = 3 ~ 5 mm; The groove depth t = 4 ~ 5 mm.
3. The labyrinth: when a maze qu road after filling grease, its sealing effect is better than groove seal. Labyrinth seal can be divided into two kinds of forms, the radial and axial. The choice of radial and axial clearance: d 50 mm or less, a = 0.20 ~ 0.30 mm, b = 1.0 ~ 1.5 mm; D = 50 ~ 200 mm, a = 0.30 ~ 0.50 mm, b = 1.5 ~ 2.0 mm.
4. Oblique labyrinth: used for shaft deflection is larger, curved road slope with the center. Oblique curved road of labyrinth seal after filling grease can achieve good sealing effect.
5. Stamping sheet steel labyrinth: consists of stamping sheet steel, synthesis of labyrinth seal its stamping sheet steel can fit perfectly on the shaft or housing, do not need to tighten, axial structure is simple. If the stamping sheet steel labyrinth of filling grease in the road, has good sealing effect.
6. Oil slinger seal: oil lubrication, a groove on the shaft, or a ring, can be put to the outward along the radial direction of oil left churn out, by means of the oil chamber and oil bearing cover Kong Liu oil pool. Can also be close to an oil slinger is installed in place of bearing, gap seal joint and often use this structure.