JU050XP0 Sealed Four-Point Contact Thin Section Bearing – 127 × 146.05 × 12.7 mm

JU050XP0 sealed four-point contact bearing has nominal dimensions of 127 × 146.05 × 12.7 mm and a five-inch bore. LYDL lists this size as LYDL-050UU.

Construction: Double-sealed Type X thin section ball bearing.
Selection focus: Offset payloads, combined loading and support stiffness in compact indexing mechanisms.
Mounting envelope: 9.525 mm radial section and 12.7 mm axial width.
Quotation requirements: Supply your mounting drawing, force locations, motion cycle and inspection criteria.

Request a LYDL configuration and drawing review. Manufacturer reference ratings in the details below are attributed separately and do not establish LYDL supply performance.

JU050XP0 Sealed Four-Point Contact Bearing for Offset Loads

The JU050XP0 sealed four-point contact bearing has a 127 × 146.05 × 12.7 mm nominal envelope. Its five-inch bore and double-sealed Type X construction provide a starting point for compact indexing-table designs carrying radial force, axial force and overturning moment. LYDL identifies this size as LYDL-050UU. For an offset tool or workpiece, the central selection question is how force reaches the bearing—not simply how much the payload weighs.

Dimensions: Reserve Space for the Complete Support

Dimension	Inches	Millimeters
Bore, d	5.000	127.000
Outside diameter, D	5.750	146.050
Axial width, B	0.500	12.700
Radial section, (D − d) / 2	0.375	9.525

The LYDL sealed Type X series table lists this envelope under LYDL-050UU. Allow additional space for shaft shoulders, housing walls, retention and assembly access. The 127 mm bearing bore is a seating dimension, not a guaranteed clear passage through the finished machine.

Reference Ratings and Their Limits

These are Kaydon JU050XP0 reference ratings, taken from manufacturer catalog [1]. They do not establish LYDL bearing performance.

Rating	Original value	SI conversion
Dynamic radial	1,600 lbf	7.117 kN
Dynamic axial	2,540 lbf	11.298 kN
Dynamic moment	3,226 lbf·in	364.489 N·m
Static radial	2,590 lbf	11.521 kN
Static axial	6,460 lbf	28.736 kN
Static moment	6,950 lbf·in	785.245 N·m

Values are rounded conversions. Dynamic capacity is based on one million revolutions of L10 life; static capacity assumes rigid support. Individual ratings cannot be applied simultaneously at their full values. Kaydon also lists 500 rpm and 4.3 lbf·in (approximately 0.486 N·m) maximum no-load torque. The speed value applies at loads up to 20% of dynamic capacity. The torque condition includes standard internal fit and lubricant, room temperature and 5 lbf axial load. Neither value defines the performance of a loaded indexing machine.

Calculate the Offset Before Comparing Capacity

For a force acting with a perpendicular offset, the associated moment is M = F × e. For example, a 100 N force acting 80 mm from its reaction axis creates an 8 N·m moment contribution. This example illustrates geometry only. It is not an approved JU050XP0 load case. The complete assessment must also include other forces, their directions, acceleration, shock and the required operating life. For an indexing fixture, record three operating states:

State	Information needed
Loading and clamping	Workpiece position, clamp-force path and any unsupported overhang
Acceleration and stopping	Rotating inertia, acceleration profile and peak forces
Processing or inspection dwell	External tool force, payload offset and permissible displacement

A short, well-supported load path can be more useful than increasing bearing diameter without changing the structure. Where possible, bring the applied force closer to its supporting plane and check the surrounding plate and housing stiffness. Submit your load diagram and request a JU050XP0 selection review.

Application Example: A Five-Inch-Seat Indexing Table

A compact table carrying an eccentric fixture may load the bearing differently at each station. Map the heaviest workpiece, the furthest overhang and the highest process force rather than assessing only a balanced, unloaded table. If an axial force acts away from the rotation axis, it contributes an overturning moment. If a tangential force acts at the table rim, it creates drive-axis torque. These quantities must be distinguished when specifying the bearing, motor and transmission. For dimensional inspection, define allowable displacement at the actual measurement point. Bearing catalog capacity alone does not establish positioning accuracy or angular stiffness. This is a design example, not a documented LYDL customer installation.

Mounting and Sealing for Repeatable Operation

Retain each ring securely without using the retaining hardware to impose an unspecified preload. Agree the required internal condition with the supplier and check the assembly after tightening. Review shoulder support, seat roundness, housing stiffness and clearance around the seals. Assembly force should pass through the ring being installed. Specify lubricant and seal compatibility with the actual contaminants and temperature; double sealing is not a washdown rating.

Brand Designations: Compare Configuration, Not Just Dimensions

Brand	Reference	Identification notes
KAYDON	JU050XP0	J denotes standard steel construction with two nitrile seals; 050 is the five-inch bore code; X identifies four-point contact. P and 0 identify separator and precision respectively.
INA / Schaeffler	CSXU 050.2RS	CSX four-point contact family, U section, five-inch size; .2RS denotes seals on both sides.
NSK	NBX12712DD	Sealed NBX catalog entry with the same nominal 127 × 146.05 × 12.7 mm envelope. Retain the DD suffix when specifying this configuration.

Catalogs [1]–[3] support these references. Equal envelopes do not prove equal ratings, seal friction, stiffness or accuracy. Brand-specific suffixes are not transferable, and Kaydon’s final 0 does not automatically specify LYDL ISO P0 accuracy.

Choosing Between Nearby Sizes

Reference	Bore × outside diameter × width, mm	Dimensional consequence
JU040XP0	101.60 × 120.65 × 12.70	Smaller seat and outside envelope
JU045XP0	114.30 × 133.35 × 12.70	Intermediate 4.5-inch seat
JU050XP0	127.00 × 146.05 × 12.70	Five-inch seat evaluated here
JU060XP0	152.40 × 171.45 × 12.70	Larger seat and housing pocket

Review JU040XP0 for smaller sealed rotary fixtures if the installation permits a smaller envelope. JU045XP0 and JU060XP0 are dimensional comparison options; neither fits the JU050XP0 seats directly. See currently published models in the Sealed Four-Point Contact Bearings category.

Define the LYDL Supply and Acceptance Requirements

Request confirmation of ring and rolling-element materials, cage, seal material, grease, internal clearance or preload, accuracy and applicable load ratings. The order should identify the drawing revision and required inspection records. For an eccentric fixture, distinguish bearing inspection from machine acceptance: a component runout result does not prove that the assembled table meets its loaded displacement target. Specify marking, individual protection and shipment packing with the order.

JU050XP0 Selection Questions

How should I describe an off-center payload?

Provide its mass, center-of-gravity coordinates and the bearing orientation. Add external forces and their application points; payload mass alone does not define the bearing moment.

Is the moment rating the torque my motor can transmit?

No. Overturning moment loads the rotary support, while drive torque acts about the rotation axis. Assess the bearing loads and drive requirements separately within the complete mechanism.

Does 500 rpm tell me how many indexing cycles are permitted?

No. Cycles depend on indexing angle, acceleration, dwell and loading. The catalog speed limit does not specify an allowable cycle rate or fatigue life for your motion profile.

Should I tighten the retaining ring until all movement disappears?

Do not use uncontrolled tightening to establish preload. Specify the bearing’s internal condition and retention design, then verify the installed assembly against agreed limits.

When should I investigate JU060XP0 instead?

Consider it when the design requires a six-inch bearing seat and can accommodate the larger housing pocket. Recalculate loading and support stiffness; a larger envelope alone does not guarantee the required accuracy.

Request a JU050XP0 Quote and Drawing Review

Identify the inquiry as JU050XP0 reference / LYDL-050UU. Send quantity, destination, timing, mounting drawing, load diagram, motion cycle and acceptance criteria. Request a JU050XP0 quotation. Ask for the proposed LYDL configuration and confirmed supply ratings before approving the order.

Manufacturer References

These publications support reference-model identification and engineering comparison; they are not LYDL product certifications.