Industrial leather: a modern and high-performing material for your seals and bellows
With the rise of polymers in the 1970s and 1980s, many manufacturers progressively set leather aside. Yet this material that we have been working with since 1893 has lost none of its technical relevance. On many applications, leather offers performance that synthetic elastomers struggle to replicate, at a cost and within lead times that these same materials do not always allow. Here is why we continue to choose it for your leather seals and bellows and why you should look at it more closely.
Industrial leather: a low-flammability material with unique properties
Do you know why welders' aprons have been made of leather for centuries? Because leather does not ignite easily. This is a natural property of the material, independent of any added chemical treatment. When correctly prepared, leather successfully passes flammability tests of the type Vertical gantry test CS 25 / FAR 25 25853 Appendix F part 1, a standard used notably in aeronautics. For your applications in environments exposed to heat or incandescent projections, this is a concrete advantage that few synthetic materials can claim without additional treatment.
Exceptional mechanical resistance for your dynamic seals
The internal structure of leather consists of an interlaced fibre network which gives it remarkable physico-mechanical properties. Tear resistance, natural flexibility, low permanent deformation, good force and elongation at break. These characteristics are measured and certified according to ISO standard 388, one of the reference methods for characterising the mechanical properties of leather. On reciprocating or dynamic motion applications, this fibrous structure allows leather to absorb repeated stresses without fatigue or lasting deformation. This is precisely why our dynamic leather seals often last longer than their synthetic equivalents on cylinders, presses and reciprocating pumps.
Leather, a natural material with low environmental impact
Leather is a by-product of livestock farming. The bovine hide is a perishable co-product that, without processing, would simply be eliminated. Its transformation into industrial leather gives it a useful second life. In 2009, 1,250 million m2 of leather were produced from this hide valorisation. Its environmental impact is measured and controlled. Tanneries that practise modern and controlled processes ensure industrial effluent treatment compliant with European standards. On the greenhouse effect indicator, chrome-tanned leather represents 8.8 kg of CO2 per m2. For a natural, durable material derived from an existing by-product, this is a footprint that many synthetic polymers cannot match across their full lifecycle.
Variable density to adapt leather to your application
Leather is characterised by a density of 0.6 to 0.95 g/cm3 depending on the species and types of hide preparation. This variability is a concrete technical advantage. It allows us to precisely select the type of leather best suited to your application according to the weight, flexibility or resistance constraints you specify. A denser leather for a high mechanical stress application. A more flexible leather for a fast-moving dynamic application. We primarily select bull and ox hides of at least four years old, thicker and more resistant than young hides, because our industrial applications demand it.
Leather versus polymers: when to choose one over the other?
Leather is not the solution to everything. But on certain applications, it is clearly superior to synthetic elastomers. When you need a custom seal quickly, without tooling costs, for a reciprocating motion application or in an environment with flammability risk, leather is often the best answer. Polymers take over when resistance to very aggressive chemicals is the primary criterion, or when temperatures exceed leather's limits. Our design office helps you choose the right material for your actual application, without bias.
Leather seals and bellows manufactured since 1893 in Reyrieux
We have been working with industrial leather for more than 130 years. We know its properties, its limits and its applications better than anyone in Europe. We hold the Entreprise du Patrimoine Vivant label and are certified ISO 9001 and ISO 14001 for the production of leather seals and bellows. If you have an application where you are hesitating between leather and a synthetic material, send us your need. We give you our technical opinion straight.