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Tie-Rod vs Welded Mill Cylinder Construction

Tie-rod and welded cylinders solve the same job in very different ways. The tie-rod type is fully serviceable and easy to repair, while the welded design is compact and handles higher pressure. This guide compares both constructions by pressure, length, maintenance and application so you can choose with confidence.

5 minStand: 2026-07Geprüft: Hydraulics specialists
View hydraulic cylinders
210 bar
Typical tie-rod rated pressure
350 bar
Common welded reserve
4 rods
Serviceable for repair
up to 20 %
Shorter welded length
Inhalt
  1. Principle
  2. Selection
  3. Maintenance
  4. Frequently asked questions

How do the two constructions differ?

On a tie-rod cylinder, four through-rods clamp both end caps against the tube. The unit can be fully dismantled and rebuilt with spare parts. On a welded cylinder the rear cap is welded straight to the tube and the head is bolted or joined too. That yields a compact, very stiff unit that stays sealed for the long haul.

Tie-rod cylinders are the industrial standard to ISO 6020/2 and easy to swap. Welded cylinders dominate mobile and heavy-duty work, where space and pressure decide.

When does each construction fit?

Choose tie-rod when serviceability, spare-part availability and changing mounting setups matter. The welded design is first choice for high pressure, shock loads, tight space and rough outdoor duty. Working pressure, environment and your planned maintenance make the call.

  • Tie-rod for on-site repair and standard mounts to norm.
  • Welded for pressures above 250 bar and heavy shock loads.
  • Welded for tight installations and mobile machines.
  • Tie-rod for frequent seal changes and series machinery.
Seals & oil

The seal kit and oil cleanliness set the service life of both types.

Compare cylinders
Stroke & buckling

Long strokes need larger rods against buckling, whichever construction you pick.

Cylinder guide
Sizing

Our specialists check pressure, stroke and mounting for your case.

Ask for advice

How do maintenance and repair compare?

A tie-rod cylinder is loosened, cleaned and rebuilt with a fresh seal kit, often without removing the whole machine. On a welded cylinder usually only the bolted head is accessible; a crack in a weld normally turns the unit into a replacement part. In return the welded form has fewer leak paths and no tie-rods that can loosen under cyclic load.

Clean hydraulic fluid protects both types - a suitable oil cleanliness to ISO 4406 cuts seal and rod wear sharply. When in doubt, ask our hydraulics specialists.

Frequently asked questions

Can a tie-rod cylinder handle high pressure too?

Yes, common tie-rod cylinders to ISO 6020/2 run safely up to about 210 bar. For sustained higher pressure or heavy shock loads, the welded construction with reserves near 350 bar is the more robust choice.

Why do tie-rods sometimes loosen?

Under cyclic and shock loads the tie-rod nuts can lose their preload. Torque the rods to the maker's specified value in a crosswise pattern and check them at each service interval.

Can I repair a welded cylinder?

Seals and the bolted head can often be replaced. Damage to the tube or a weld usually makes the unit a replacement part, since a safe re-weld is rarely economical.

Find the right hydraulic cylinder

Our hydraulics specialists help you choose between tie-rod and welded construction by pressure, stroke and application.

Neutral selection

Recommendations from norms and field values, vendor-neutral.

Correct pressure

Construction matched to working pressure and shock load.

Maintenance in mind

Repair and spare parts planned from the start.

Expert advice

Hydraulics specialists support your sizing.