Combination Seals and Durable Seals for Hydraulic and Gearbox Use

When people in the industrial field talk about sealing solutions, most of the
time they first mention O-rings or maybe lip seals. But, you know, those are
just part of the picture. In actual practice, especially when pressure cycles
are not steady or when media are mixed—think hydraulic oil plus fine
particles, or pumps in a gearbox running hot—the so-called Combination Seal
Series starts to make more sense.

What actually is a Combination Seal?

In case you are not deep in sealing jargon, it’s basically a seal that blends
multiple functions—often an O-ring plus a back-up ring, or an elastomer lip
reinforced with a PTFE element. Materials can vary: NBR, FKM, HNBR for the
elastomer part; PTFE or engineered plastics for the secondary ring. The reason
is simple: one material alone can’t handle high pressure plus extrusion risk
plus temperature swings. Together, the combination can.

Typical working conditions?

· Pressure ranges: up to 40 MPa in hydraulic systems.

· Temperature: depending on material, from -40 °C up to 250 °C.

· Media: hydraulic fluids, gear oils, some chemical agents, water-glycol
solutions.

Application fields

Now, where does this matter? Pumps and motors, of course. But also gearboxes in
heavy trucks, excavators in construction, wind turbines (the nacelle has to
live with continuous load), and hydraulic cylinders in agricultural machines.
Even robotic arms use them, because stability in motion means reduced downtime.

So the audience for such seals is not only engineers on the plant floor.
Distributors, maintenance companies, and OEM buyers are paying attention. They
look for a stock that is reliable, standardized, but also options for
customization.

About DEDE and why the service style matters

One thing I keep hearing from resellers is: “Speed of supply is everything.”
If the line stops, nobody waits for a shipment two weeks later. That’s why
DEDE keeps over ten thousand types of standard seals (O-rings, oil seals, etc.)
in stock. Standard parts ship quickly—that solves emergencies.

But standard isn’t the full story. Non-standard requirements keep showing up.
For that, the company provides full customization service: from material choice
(say, switching from NBR to HNBR because of heat and oil), to structure design
(like adding a PTFE support ring), and through to production tests. The outcome
is that the seal actually matches the application, not the other way round.

DEDE has been around for more than 30 years, the technical team does more than
supply parts—they help optimize sealing systems to cut down maintenance costs.
That point is often underestimated. For a distributor, if your client saves on
maintenance, they come back to you.

Enterprise highlights

· Real manufacturing factory, not just trading.

· Recognized as a leader in the sealing industry.

· Complete model range, meaning you don’t have to shop around.

· Exporting to 80+ countries—global presence signals stability.

· Partner for well-known international brands.

· Holds status of Provincial Technology Innovation Center.

· Acknowledged as Specialized and Innovative enterprise.

· Certified High-tech enterprise.

· Leading player in a specialized industrial cluster.

For a wholesaler or distributor, these credentials reduce risk. You don’t want
to sell products from a supplier that disappears in two years.

FAQ

Q: How fast can we get delivery for standard sizes?

A: Usually within a few days. Inventory covers common O-rings, oil seals, and
combination seals.

Q: What about MOQ for customized seals?

A: Depends on the size, but the company is flexible with smaller runs, which
helps distributors test markets.

Q: Do you provide technical documents for end-clients?

A: Yes. Material data sheets, pressure limits, and even installation guides are
available. That way, resellers don’t need to prepare everything themselves.

Q: How about warranty or support after sales?

A: With decades of projects in pumps, motors, gearboxes, and even robotics, the
team knows failure modes well. That experience is part of the support, not just
words on paper.

Why the combination design really matters in practice

Let’s be honest: seals are small parts. Easy to ignore. But when a seal fails,
the downtime cost is huge. Imagine a wind turbine stopped in mid-winter because
of a leaking hydraulic cylinder—that’s thousands of dollars per hour. By
integrating back-up rings, anti-extrusion features, or dual-lip configurations,
combination seals reduce those risks.

In a way, it’s like insurance: the upfront cost may be higher than a single O-
ring, but the avoided breakdowns make the choice rational. That’s also why OEM
in sectors like heavy machinery or energy prefer them.

The Combination Seal Series is not about a single clever product. It’s a whole
approach: merging materials, designs, and services to match real industrial
life. DEDE is approach—stock for speed, customization for accuracy, and
experience for guidance—has already placed its seals in pumps, gearboxes,
heavy trucks, agricultural machines, and even robotic systems worldwide.

Minimum Order: 500 pieces

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