Description
Screw Conveyor Universal Joint Bodies and Inlet Assemblies
The Screw Conveyor Universal Joint is a hollow spherical connection used between a silo or butterfly-valve outlet and an inclined screw conveyor inlet.
It forms part of the material passage and does not transmit torque between rotating shafts.
We manufacture one-piece spherical bodies, matching retaining parts and complete conveyor inlet assemblies from drawings, confirmed dimensions or existing samples.
One-Piece Spherical Body with a Clear Material Passage
Hot-Formed Spherical Structure
The main body is formed as an integrated spherical section rather than assembled from multiple small curved plates.
This provides:
- A consistent spherical profile
- Fewer welded joints around the seating surface
- Stable contact with the clamp or retaining seats
- Better dimensional consistency for replacement work
Thick-Wall Carbon Steel
Thick-wall carbon-steel construction is suitable for cement, fly ash, lime, mineral powder and other dry bulk materials.
Wall thickness can be specified according to:
- Opening diameter
- Material abrasiveness
- Existing component dimensions
- Required connection strength
Stainless-steel construction is also available for confirmed corrosion or material-contact requirements.
Smooth Internal Passage
The hollow body contains no cross shaft, coupling or internal transmission mechanism.
Material passes directly through the spherical section into the screw conveyor inlet, reducing sharp internal corners and unnecessary restriction points.
Matched Retaining Geometry
The spherical diameter, retaining shoulder and neck positions are manufactured as one dimensional relationship.
When supplied with a clamp or retaining seats, the mating parts are checked together before shipment.
Supply the Part You Actually Need
| Supply Form | Recommended When |
|---|---|
| Spherical Body Only | Existing clamp, seats and connection parts remain usable |
| Body with Retaining Clamp | Original clamp is worn, distorted or missing |
| Body with Matching Seats | Existing contact surfaces no longer fit evenly |
| Body with Connection Necks | Upper or lower connection also requires replacement |
| Joint Welded to Conveyor Inlet | Site positioning and welding need to be reduced |
| Complete Inlet Connection Assembly | Several original parts are damaged, modified or unavailable |
A body-only replacement is suitable only when the retained parts still have the correct shape and dimensions.
Where the original clamp, seats or necks have been repeatedly repaired, a complete matched assembly is usually more dependable than combining new and worn components.
Dimensions That Control the Fit
A Universal Joint cannot be identified by opening diameter or spherical diameter alone.
| Dimension | Function |
|---|---|
| Upper Opening Diameter | Matches the silo outlet or butterfly valve |
| Lower Opening Diameter | Matches the screw conveyor inlet |
| Spherical-Body Diameter | Fits the retaining clamp or seats |
| Upper Neck Diameter | Matches the upper sleeve, pipe or flange |
| Lower Neck Diameter | Matches the conveyor inlet connection |
| Upper Neck Length | Controls upper-side engagement |
| Lower Neck Length | Controls lower-side engagement |
| Overall Height | Defines the total connection length |
| Retaining-Shoulder Position | Locates the body inside the retaining parts |
| Wall Thickness | Determines body section and internal opening |
| Assembly Orientation | Fixes the position of a welded inlet assembly |
Two bodies with the same upper and lower openings may still be incompatible if their overall height, neck lengths or retaining-shoulder positions are different.
The dimensions of the existing clamp and seats should also be confirmed when they will remain in service.
Replacement from a Sample or Drawing
Replacement production can be based on:
- An approved technical drawing
- A dimensioned hand sketch
- A complete old sample
- Measurements from retained clamps and seats
- A screw conveyor inlet drawing
- A complete inlet connection assembly
When measuring a worn sample, dimensions should be taken from the least-damaged surfaces and compared with the parts that will remain in use.
Important reference points include:
- Spherical contact surface
- Retaining shoulder
- Upper and lower necks
- Original insertion depth
- Overall installed height
- Clamp and seat profiles
Photographs should be taken before the old assembly is dismantled, especially when parts have previously been cut, welded or modified.
Available Manufacturing Configurations
| Item | Available Configuration |
|---|---|
| Material | Carbon steel or confirmed stainless steel |
| Upper and Lower Openings | Equal or different diameters |
| Neck Dimensions | Standard or produced to drawing |
| Wall Thickness | Produced to confirmed requirements |
| Supply Condition | Loose body, matched retaining set or complete assembly |
| Conveyor Inlet | Supplied separately or welded to the joint connection |
| Surface Treatment | According to the approved project requirement |
| Production Basis | Drawing, dimensions or measurable sample |
A complete welded inlet assembly can reduce on-site cutting, positioning and welding.
Before production, the finished orientation, insertion depth and interface dimensions must be fixed on the approved drawing.
Information Required for Production
Spherical Body Only
Please provide:
- Upper and lower opening diameters
- Spherical-body diameter
- Upper and lower neck diameters
- Upper and lower neck lengths
- Overall height
- Retaining-shoulder dimensions
- Wall thickness
- Material
- Quantity
Body Used with Existing Retaining Parts
Also provide:
- Clamp inside dimensions
- Clamp profile
- Seat dimensions
- Contact-surface photographs
- Original installed position
- Details of previous repairs
Complete Inlet Assembly
Please include:
- Silo or butterfly-valve outlet dimensions
- Screw conveyor inlet dimensions
- Finished assembly height
- Required orientation
- Welding requirements
- Surface-treatment requirements
- Components required in the finished assembly
- Quantity
Clear photographs should show the component from several directions and include a ruler or measuring scale.
Frequently Asked Questions
We only have the old spherical body and no drawing. Can you manufacture a replacement?
Yes, when the main dimensions can still be identified.
We need the opening diameters, spherical diameter, neck dimensions, overall height and retaining-shoulder position. Measurements from the original clamp and seats are also recommended when those parts will be reused.
The old clamp is no longer perfectly round. Can we order only the spherical body?
A new body may not seat correctly inside a distorted clamp.
Measure the clamp in several directions and inspect its contact surfaces. When its internal profile has changed, ordering a matched body and clamp is normally the safer option.
The opening diameters are correct, but the new body is shorter than the old one. Can it still be used?
Not without checking the complete connection.
A different overall height or neck length changes the insertion depth and the position of the spherical body inside the retaining seats. The replacement should match the original dimensions or an approved revised drawing.
Can the upper and lower connections have different diameters?
Yes.
Different diameters can be produced when the silo outlet and conveyor inlet use different connection sizes. The neck dimensions, wall thickness, internal transition and overall height must be confirmed together.
Can the Universal Joint be supplied already welded to the screw conveyor inlet?
Yes.
It can be supplied with the lower connection neck or as part of a complete conveyor inlet assembly. The required orientation, insertion depth and finished interface dimensions must be confirmed before welding.
