QJ338-N2-MPA-C3-FAG Four Point Contact Ball Bearing 190x400x78mm

In stock
SKU: QJ338-N2-MPA-C3-FAG
FAG Four Point Contact Ball Bearing with solid brass cage, C3 clearance & locating slots 190mm inside x 400mm outside x 78mm wide
Regular price £5,145.26 inc.VAT
£4,287.72 exc.VAT
FREE UK MAINLAND DELIVERY ON ORDERS OVER £50

Product details

  • Vendor FAG
  • SKU QJ338-N2-MPA-C3-FAG
  • Inside diameter (d) 190mm
  • Outside diameter (D) 400mm
  • Width (B) 78mm
FAG Four point contact bearings are similar in their structure to double row angular contact ball bearings, but are considerably narrower in an axial direction due to only one raceway groove. Since the centres of curvature of the arc-shaped raceways on the inner ring and outer ring are offset relative to each other, the balls are in contact with the bearing rings at four points under radial load. For this reason, four point contact bearings are only used under predominantly axial load.

If predominantly radial load is present, four point contact bearings should not be used due to the higher friction in the four point contact.

One of the two bearing rings, normally the inner ring, is split for assembly reasons in order to allow filling with the balls. As four point contact bearings are often fitted without radial retention, the outer rings can be designed as an option with retaining slots to prevent rotation.

A main area of application is in gearbox engineering, where axial loads are present in both directions and close axial guidance is required in conjunction with a small bearing width.

Four point contact bearings are often combined with a radial bearing and used as an axial bearing with radial clearance in a housing.

Main Dimensions & Performance Data
d 190 mm Bore diameter
D 400 mm Outside diameter
B 78 mm Width
C r 740,000 N Basic dynamic load rating, radial
C 0r 1,250,000 N Basic static load rating, radial
C ur 40,500 N Fatigue load limit, radial
n G 2,850 1/min Limiting speed
n ur 1,320 1/min Reference speed
51.4 kg Weight

Mounting dimensions
d a min 210 mm Minimum diameter shaft shoulder
D a max 380 mm Maximum diameter of housing shoulder
r a max 4 mm Maximum fillet radius

Dimensions
r min 5 mm Minimum chamfer dimension
D 1 329.1 mm Shoulder diameter outer ring
d 1 263.9 mm Shoulder diameter inner ring
a 207 mm Distance between the apexes of the pressure cones
a n 12.7 mm Hight retaining slot
b n 10.5 mm Width retaining slot
r n 2 mm Radius retaining slot
45 Degree angle retaining slot
35 Degree contact angle

Temperature range
T min -30 Degree celsius operating temperature min.
T max 200 Degree celsius operating temperature max.

Design, bearing outer ring N2 two retaining grooves in the outer ring on one side
Cage MPA solid brass cage, outer ring guided
Tolerance class PN Normal (PN)
Dimensional / heat stabilization S0 Rings dimensional stabilized up to 150degree celsius
Axial internal clearance C3 Group 3 (C3), bigger than CN