687.55 weld yoke for 2055-series 57×152 mm universal joints and 120×6 mm driveshaft tube. Forged steel construction with machined bearing bores and nominal 108 mm weld-fit bore.
687.55 Weld Yoke for 120×6 mm Tube | 2055 Series 57×152
Description
Product Overview
The 687.55 weld yoke is a forged tube yoke for heavy-duty 2055-series driveshafts using a nominal 57×152 mm universal joint and 120×6 mm drive tube. Its bearing seats and weld-fit end are machined after forging to control joint alignment and tube connection geometry.
This component is designed for professional propeller-shaft manufacture and repair. Tube size, bearing diameter, joint span and the centreline-to-weld geometry must be verified before welding.
Tube Connection
The weld end is configured for nominal 120 mm outside-diameter tube with 6 mm wall thickness. The corresponding nominal inside diameter is 108 mm. Before assembly, check actual tube dimensions, weld-end fit, runout and the required weld preparation. Do not force a mismatched tube into the yoke or correct excessive clearance with weld metal.
Technical Specifications
| Product type | Weld yoke / tube yoke |
|---|---|
| Series | 687.55 / 2055 |
| Nominal U-joint size | 57×152 mm |
| Tube size | 120×6 mm |
| Nominal weld-fit bore | 108 mm |
| Material form | Forged steel |
| Machined features | Bearing bores and tube-fit surface |
| Surface condition | Shot-cleaned forged body with machined functional surfaces |
Manufacturing and Inspection
The forged body retains material around the yoke ears and transition area, while the bearing bores are machined for the 57 mm joint family. The tube-fit diameter must remain concentric with the yoke axis because weld-end offset becomes driveshaft runout after assembly.
Recommended incoming checks include bearing-bore diameter, bore-to-bore alignment, yoke span, tube-fit diameter, weld-end squareness and visible forging condition. After welding, the shaft should be checked for runout, phasing and balance as required by the complete driveshaft specification.
Series References and Fitment
The terms 687.55 weld yoke, 68755 tube yoke and 2055 series weld yoke are commonly used for this component family. Related 587.42 references may also appear in drawings or aftermarket catalogues. Series numbers are identification aids only; confirm the 57×152 mm joint and 120×6 mm tube interface before replacement.
687.55 Series Matching Components
| Component | Primary identifier |
|---|---|
| Slip assembly | 57×152 mm joint, 120 mm sleeve |
| Weld yoke | 120×6 mm tube |
| Cross-serrated flange yoke | 180 mm, 4-bolt pattern |
| Universal joint | 57×152 mm |
Ordering Checklist
Send the required quantity together with the joint size, tube outside diameter and wall thickness, weld-end inside diameter, centreline-to-weld measurement and clear side and end photographs. When replacing an existing yoke, also provide any casting marks and the dimensions of the original component.
Frequently Asked Questions of 687.55 weld yoke
Is this weld yoke for 120 mm solid bar?
No. It is intended for driveshaft tube identified as 120×6 mm, subject to actual fit verification.
Can a 120×5 mm or 120×8 mm tube be used?
Do not assume so. A different wall thickness changes the tube inside diameter and weld-end fit. Confirm both tube OD and wall thickness.
Does the weld yoke determine final shaft balance?
It affects alignment and runout, but final balance applies to the complete welded and assembled driveshaft.
Contact MR Driveline for 687.55 weld yoke drawings, dimensional confirmation and export quotation.
Additional information
| Brand | MR Driveline |
|---|---|
| Series | 687.55 / 2055 |
| U-Joint Size | 57×152 mm |
| Tube Size | 120×6 mm |
| Nominal Weld-Fit Bore | 108 mm |
