Where does the
spacer work?
Every spacer in a turbine sits in or near water, so each stack needs a spacer that stays flat and stays free.
Bearing stacks
Spacers between bearing faces set the stack length. Uneven spacers leave the components out of flush and wear the bearings faster.
Mounting studs
A spacer over a mounting stud needs a slide fit that stays free after years underwater, so later service is quick and safe.
Turbine housings
Spacers in the housing are wetted by fast, aerated water. Carbon steel pits there, so stainless is the starting point.
Drive train joints
Misaligned components pass vibration into the drive train. Flat, parallel spacer faces keep the joint square.
Choose the grade, faces,
and fit together.
Do not select a spacer from the word “stainless” alone. The grade, the face finish, and the bore fit each decide how the stack behaves underwater.
316L stainless
316L suits constant water contact. Confirm the water chemistry of the site, including chlorides, before treating it as a universal fit.
Grade follows the waterSurface-ground end faces
Grinding makes the end faces flat and parallel, so the stack sits flush and the components do not rock.
Flatness follows the stackSlide-fit bore
A slide fit over the studs makes seizing less likely after years in water, which makes later maintenance faster.
Fit follows the stud toleranceWater, flatness, and seizing each need their own check.
Corrosion, vibration, and hard service each push toward a different detail.
| Condition | What to review before specifying |
|---|---|
| Constant submersion | Spacers that stay wet for years need a grade chosen for the water. Confirm the chlorides and the flow conditions of the site. |
| Fast, aerated water | Carbon steel spacers pit in fast, aerated water, and uneven pitting leaves the stack out of flat. Stainless avoids that pitting; confirm the grade against the site chemistry. |
| Uneven faces | Faces that are not flat and parallel rock the components and set off vibration. Specify flatness and parallelism as critical dimensions. |
| Seizing on studs | A spacer that seizes on a stud makes service slow and risky. Specify a slide fit and check it after installation. |
| Dissimilar metals | Carbon steel or aluminum next to stainless in wet service can form a galvanic pair. Match the materials where the design allows. |
Tell us where
the spacer sits.
The most useful enquiry contains the real stack and water conditions around the spacer, not only a nominal bore size.
- ApplicationBearing stack, mounting stud, housing joint, or other
- StackBearing model, the faces that touch the spacer, and the stack length
- BoreStud or shaft diameter and the fit you need
- FacesFlatness and parallelism required at the end faces
- EnvironmentWater flow, aeration, chemistry, and temperature
- Material316L or another stainless grade
- SizeOutside diameter, inside diameter, and length
- DocumentsDrawing, sample or worn part, quantity, and required finish
Field result: a quieter turbine.
A regional hydropower plant replaced corroded mounting spacers with surface-ground 316L stainless spacers. The plant reported that the turbine runs quieter and that the emergency shutdowns for vibration have stopped.
Before you
place the order.
Use these questions to turn an application description into an engineering review.
Why grind the faces of a turbine spacer?
Grinding makes the end faces flat and parallel so the stack sits flush. Uneven faces let components rock, which shows up as vibration.
Is 316L the right grade for hydropower?
316L suits constant water contact. Chloride content and flow conditions vary by site, so tell us the water chemistry and we will confirm the grade.
How do you stop spacers seizing on studs?
We machine a slide fit on the bore and supply stainless, which does not rust onto the stud. Send the stud diameter and tolerance and we will set the fit.
What should I send for a hydropower spacer?
Send the bearing model, stack length, stud diameter, and the flatness you need. Add the water chemistry and quantity, and a drawing or the worn part helps.