Fine Flow Technologies LLP

The diaphragms are the parts subjected to the greatest stresses during suction and pumping, whilst also having to resist the chemical attack and temperature of the liquid and the mechanical fatigue. A modern design process, destructing testing, as well as an in-depth analysis of the results have allowed Debem to develop the new generation LONG LIFE diaphragms. Thanks to their profile and construction shape, these products offer a larger working surface and improved redistribution of the load, reducing the stress and yield of the material to a minimum. The profile of our diaphragms is designed so that the mechanical stress (in expansion) is distributed along the whole profile, so that there is one point with the greatest stress. On other diaphragms with a similar design the stress is applied on various points which can compromise the life of the diaphragm. The diaphragms are available in a vast range of materials.

Thermoplastic diaphragms

Made with thermoplastic polymers, these diaphragms provide a high level of mechanical resistance and stress distribution:

• L’HYTREL® is a thermoplastic material with unique characteristics such as a high resistance to impact, flex fatigue and creep. At low temperatures it maintains an excellent flexibility under stress and at high temperatures it maintains most of its properties. It is also resistant to the attack of many industrial chemicals, oils, solvents, acid and alkaline fluids, amine and glycol.
• SANTOPRENE® has an excellent resistance to acid and alkaline fluids, high flexural resistance and good abrasion resistance.

This material is known for its considerable resistance to temperature and chemical and corrosive agents. Diaphragms in Debem PTFE undergo a double heat treatment to increase their elasticity and service life. A sample of each batch is subject to destructive tests to check their compliance with the technical requirements. This diaphragm can be installed combined with one of the ones examined earlier (HYTREL® – SANTOPRENE®), in order to increase the resistance to the corrosive chemical agents and temperature of the fluid. PTFE is chemically inert and practically impenetrable. Not suitable for use with molten alkaline metals, abrasive liquids, suspended solids, chlorine or oxygen trifluoride or difluoride.

Debem’s rubber diaphragms offer high resistance and a unique mechanical bending capacity, thanks to the special additives in the rubber mixture that also improve the chemical characteristics. They also have an internal nylon cloth reinforcement that improves stress distribution across the surface.

• NBR: Inexpensive and particularly suited for petroleum-based liquids, aliphatic hydrocarbons, oil and abrasive fluids whilst on the other hand it is not suited for chlorinated solvents or acids.
• EPDM: Good resistance to acids, alkaline and abrasion as  well as a good flexibility also at low temperatures. Not suitable for oil and mineral greases.

• Our plastic materials are reinforced with carbon or glass fibres.
• Our polypropylene undergoes a stabilisation process: the parts, once moulded, are placed in an oven for 60° C, for about 15 minutes, and then left to cool naturally.
• Our aluminium is obtained through a procedure called die casting, using a high quality raw material, that is the same as the one used in the automotive industry.
• Our SS 316 s certified by our Italian supplier, with tests at the end of every production batch, that guarantee that only SS 316 is used to produce the parts.
• Our PTFE undergoes special treatments to render it more elastic and resistant to fatigue and wear. Elimination of the crystalline. Ensuring that during application there is absolutely – NO DEFORMING. Heat treatment similar to metal tempering, a continuous heating and cooling process that strengthens the molecular structure.