Frequently asked questions about
our leather seals and bellows
Why choose leather seals and bellows over elastomer ones?
Leather offers natural flexibility, friction resistance and an ability to adapt to complex shapes that elastomers do not always replicate. On dynamic reciprocating motion applications, it often lasts longer. And unlike elastomers, it does not require costly specific tooling to manufacture custom parts. This means short lead times and controlled costs even on single units.
Since when has Emile Janique been manufacturing leather seals and bellows?
Since 1893. Manufacturing has never been interrupted since that date. We have navigated more than 130 years of industrial evolution while preserving leather as our primary material. We are today the European leader in leather components for industry.
Is Emile Janique ISO 9001 certified?
Yes. We are the only European company certified ISO 9001 and ISO 14001 for the production of leather seals and bellows. Every part we deliver to you is documented and traceable. We also hold the Entreprise du Patrimoine Vivant (EPV) label.
What is the difference between a static seal and a dynamic seal?
A static seal ensures sealing between two fixed parts. It does not move. A dynamic seal works in motion, on a cylinder rod, a rotating shaft or a pump piston. If you don't know which one corresponds to your application, describe your need to us. We will direct you.
What materials do you use besides leather?
We also work with cork, NBR, EPDM, FKM elastomers, PTFE, foam, copper and aluminium according to your application and working environment. Leather remains our primary material but we always choose the material best suited to your actual need.
Can you reproduce a part whose reference I no longer have?
Yes. Send us your worn part or a dimensioned sketch. We take the dimensions and manufacture the replacement to exact measurements, even if the original part no longer exists in the manufacturer's catalogue.
Do you manufacture in small quantities or only in series?
Both. We manufacture from a single unit. No minimum quantity. That is one of the advantages of leather: no costly specific tooling, therefore no minimum imposed to amortise a mould. Single unit or large series, we handle both.
What are your lead times for leather seals and bellows?
It depends on the complexity of your part and the quantity. Send us your request with your dimensions or your part. We give you a precise lead time in our response. We manufacture everything in our workshop in Reyrieux, in the Ain, which allows us to remain responsive.
Do you deliver internationally?
Yes. We deliver our leather seals and bellows throughout France and internationally. Contact us for a quote including lead times and delivery conditions.
What information do you need to provide a quote?
For a seal, tell us the dimensions, the type of seal required, the fluid in contact and your working environment. For a bellow, send us your dimensioned drawing or sketch with the dimensions of the part to protect. If you don't have all this information, send us your existing part or describe your application. We ask the right questions to move forward.
Does leather resist oils and chemical products?
Leather naturally resists oils and light greases. For more aggressive environments with hydraulic oils, fuels or concentrated chemical products, we direct you towards treated leathers or towards FKM or NBR elastomers which offer better chemical resistance. Describe the products in contact and we will choose the right material.
Does leather hold up in humid environments?
Yes. We have developed a treatment derived from fluorinated resins that makes leather hydrophobic and allows it to work in humid environments without degrading. This treatment is applied to our parts according to your application constraints.
Do you make seals for very old machines whose parts are no longer available?
That is one of our specialities. Send us your worn part or a dimensioned sketch. We take the dimensions and manufacture the replacement in leather or in the appropriate material. Regardless of the age of the machine or whether the original part exists anywhere.
Can we send you a part directly to reproduce?
Yes. That is even the simplest way to convey your need when you don't have a drawing. Send us your existing part, we take all the necessary dimensions and manufacture the replacement. Contact us first to let us know your shipment is coming.
Where do the hides you use come from?
We source primarily in France. We purchase bull and ox hides of at least four years old, selected for their mechanical resistance. These hides are often more expensive than those used in standard leather goods because our industrial applications demand superior quality.