Rubber hydraulic seals: types, materials and production

At GBL we have been manufacturing rubber hydraulic seals for over 40 years. This is why we are fully aware of the characteristics that are essential for a quality production process for one of the most widely used items for sealing in terms of sector and use.


Here we take a look at the principal materials and best practices for the production of quality rubber hydraulic seals.


Hydraulic rubber seals: types and articles made to design

At GBL we produce all types of hydraulic seal, creating both standard products and items made according to client specifications. However, the most common types of standard hydraulic seals are the following.


  • O-rings – the most commonly used hydraulic seals.
  • Lip seals (or V-rings) – used in rods and pistons – are capable of withstanding high pressure levels.
  • Frames – used in hydraulic pumps.
  • Scraper seals – used to protect hydraulic systems from wear and contamination.


Although there are many types of hydraulic seal, the production methods used are similar, and they all have a common denominator; they are well designed, with the best possible materials.


Hydraulic seal materials: a number of products compared

Hydraulic seals are by definition made of rubber. The term rubber, however, encompasses a wide range of materials with very different characteristics.

Elastomers are, in fact, a group of natural or synthetic substances that share chemical-physical characteristics while offering a wide range of properties and types of performance.


The characteristics used to assess the most suitable material for a hydraulic seal are:

  • mechanical properties
  • resistance to deformation 
  • resistance to abrasion
  • elastic performance
  • resistance to tearing


Other material characteristics to be taken into consideration are:

  • air and gas impermeability
  • resistance to UV radiation
  • resistance to flame
  • dielectric properties


With regards to hydraulic seals, another crucial aspect is chemical compatibility. It is common for hydraulic seals to encounter problems caused by a choice of material that is not completely compatible with the liquid in question.


Polyurethane, for example, is possibly the most common material used in seal manufacture. This is due to its excellent mechanical resistance, as well as its resistance to abrasion and tearing. It is also suitable for contact with mineral oils and hydrocarbons. 

Polychloroprene (CR), on the other hand, also offers resistance to non-oxidising-acid and silicone-ester-based hydraulic fluid solutions.


Other elastomers that we process for our hydraulic seals at GBL include ACM, EPDM, FKM, VMQ, FVMQ, CR, HNBR, NBR, NBR-PVC, SBR, NR and AU. This in addition to the full range of thermoplastics and mixed materials.


The relative material therefore needs to be chosen in accordance with the situation and conditions of use. Pressure, speed, temperature, liquid and contact materials are all factors to be taken into account.


Design and production of hydraulic seals

In addition to attentive design, seal production also needs to take place in accordance with a tried and tested process. One of the most important elements in production is, for example, the quality of the mould used.

At GBL, we collaborate with GBS for this aspect. GBS is a GB Group company that designs and manufactures moulds for rubber and thermoplastic articles.


This partnership allows us to produce hydraulic and hydraulic seals and gaskets with extreme precision.


GBL for your rubber hydraulic seals

At GBL we have been manufacturing low- and high-pressure fluid-power and hydraulic seals since 1976.

The extensive range of materials, including rubber, rubberised fabric and thermoplastics, and our wide-ranging machine inventory, allow us to offer extremely flexible production.


The IATF 16949-certified control laboratory for raw materials and finished products guarantees full compliance with client requirements and specifications.

Our products include items made to design, membranes, special O-rings, hydraulic piston seals, piston water pump seals, collars and scrapers.


Are you interested in our rubber hydraulic seals or require information on materials and production? Contact us.