NTNBST30X62-1BDFP4Ball Screw Support Bearing Pair, 30x62x15 mm Each, 60° Angular Contact Thrust, Standard Preload, Face-to-Face Matched, P4

Product Description

What this part is

A matched pair of NTN BST-type ball screw support bearings, 30 mm bore by 62 mm outside diameter by 15 mm wide per bearing, supplied face-to-face. These are angular contact thrust ball bearings built specifically to locate the end of a ball screw — not general-purpose ball bearings, despite what the previous listing called them.

Correcting the source data

The record described this simply as a ball bearing and listed no contact angle, which understates it badly. NTN’s own ball screw support bearing catalogue is explicit about what a BST is: a 60° contact angle, the maximum practical number of small balls, thicker inner and outer rings than a standard bearing, and a resin cage as standard. Those four things together are the product. The order-now copy and shipping promises have also been removed.

Decoding the designation

BST — NTN’s open-type angular contact thrust ball bearing for ball screw support, 60° contact angle
30X62 — 30 mm bore, 62 mm outside diameter
1B — standard preload
DF — face-to-face matched pair
P4 — ISO tolerance class 4

Why 60° and why it matters

A ball screw end bearing has an unusual job: almost all of the load is axial, and the whole point of the machine is that the screw does not move axially under reversing load. A 60° contact angle puts the load path far closer to the screw axis than a 15° or 25° spindle bearing does, so axial rigidity is very high and the radial capacity that is not needed is traded away. Preload eliminates backlash, which is what lets the axis repeat to microns rather than tenths.

NTN grinds every BST bearing to the same stand-out on both faces. That is a genuinely useful design decision: bearings with the same number can be freely combined into DB, DF, DBT or DTBT stacks and the preload comes out right without shimming, measuring starting torque or trial-and-error tightening. It also means a face-to-face DF pair like this one can be reconfigured back-to-back if your end housing calls for it.

Published ratings and mounting data

Boundary dimensions of 30 x 62 x 15 mm per bearing and a 60° contact angle are confirmed from NTN’s catalogue, as is the resin cage and the 1B standard preload. A DF pair stacks to 30 mm overall width. Basic dynamic and static load ratings are left blank: NTN publishes them per arrangement in a table format we could not read unambiguously, and an axial rating quoted against the wrong arrangement is a serious error on a preloaded thrust set. Ask us and we will look the figure up against your specific DF, DB or DBT configuration.

Quantity and configuration

Two bearings, one DF pair. Stock is recorded as 1, which on this record means one pair. New old stock in an opened box; the item is recorded as marked made in Japan.

Interchange guidance

Sealed sibling: BST30X62-1BLXL, the light-contact-seal version of the same bearing. Three-row version: BST30X62-1BDFT. The 2A-BST30X62-1B is NTN’s alternative execution in the same envelope. Same-size ball screw support bearings from other makers include NSK 30TAC62B and the THK and Nachi equivalents; check the contact angle and preload class before substituting, because a 30° ball screw bearing in a 60° housing will give away most of your axial stiffness.