Seals for earth-moving machines and industrial plants
An excavator on site and a press in a factory both use hydraulic cylinders, but their seals face very different challenges. Here is what to consider in each case.
Hydraulics are everywhere: on construction sites, in quarries, ports and factories. The working principles of cylinders are the same, but operating conditions vary enormously, and with them the requirements for seals. Let us look at the main differences between mobile machines (earth-moving, lifting, construction) and fixed industrial plants (presses, machine tools, production lines).
Earth-moving and mobile machines
The challenges
- Aggressive outdoor environment: dust, mud, sand, water, ice and debris.
- Heavy loads and shocks: excavators, loaders and hydraulic breakers generate strong pressure peaks and side loads.
- Long, exposed rods: boom, arm and bucket cylinders have long strokes and often work extended.
- Variable temperatures: from morning frost to overheating on summer days of continuous work.
The solutions
- High-efficiency wipers, often double lip or metal-cased, to keep dirt out.
- Polyurethane rod seals or tandem sealing systems, resistant to abrasion and peaks.
- Compact piston seals with anti-extrusion rings.
- Wide phenolic resin guide rings to carry side loads.
- Static seals and O-rings suited to high pressures, with back-up rings where needed.
Fixed industrial plants
The challenges
- Very high cycle counts: some machines run several shifts, with millions of cycles a year.
- Precision: presses, machine tools and positioning systems require smooth movements without jerks.
- Speed and heat: high speeds generate frictional heat in the sealing zone.
- Different fluids: some plants use fire-resistant or special fluids that require compatible materials.
The solutions
- Filled PTFE seals with energiser, low friction and no stick-slip.
- PTFE guide rings and strips for high speeds.
- Temperature-resistant materials such as FKM at the hottest points.
- Rotary seals for swivel joints and rotary tables.
What all sectors have in common
- Quality surfaces: chromed rods in good condition and bores with the right finish are the basis of every seal.
- Clean oil: good filtration extends the life of seals, pumps and valves.
- Complete kits: during an overhaul, always replace all seals and guides of the cylinder.
- Correct installation: suitable tools, lubrication and protection of threads and edges.
Downtime and spare parts
On a site or a production line, every hour of downtime has a cost. That is why it helps to have a supplier with a large stock and fast shipping. Our catalogue includes about 160,000 references, with about 80,000 items in stock: rod and piston seals, wipers, guides, O-rings, static and rotary seals in many materials.
If you manage a fleet of machines or an industrial plant, you can prepare kits in advance for the most critical cylinders using the search by dimensions. And if you need to identify seals without a code, our technical support is available to help you find the right profile.
Frequently asked questions
Do hydraulic breakers need special seals?
In many cases yes: vibration and operating frequencies are very high and kits are often model-specific. Send us dimensions and photos so we can check the available alternatives.
How can I reduce downtime on site?
Keep kits ready for the most critical cylinders (boom, arm, bucket), check rods and wipers every day and plan overhauls during quieter periods.
Can I use PTFE seals on an excavator?
In some positions yes, for example as the primary seal in tandem systems; in the areas most exposed to dirt and shocks, polyurethane and compact profiles are often preferred.
Do industrial presses need large-diameter seals?
Often yes. For non-standard or very large diameters, contact us: we will evaluate the possible solutions together.
