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Bertolini Pump Diaphragm replacement kits

Original price $167.00 - Original price $299.00
Original price
$167.00 - $299.00
Current price $170.00

Keep your Bertolini pump in good repair with Genuine Bertolini DURAMAX diarphragm repair kits

Duramax Kits are made up of rubber wearing parts as specified by Bertolini to be service maintenance items. If you require replacement valve kits be sure to order these also.


  • Piston Diaphragms
  • Accumulator Diaphragm (model dependent - if applicable)
  • Inlet valve O-rings
  • Outlet valve O-rings

Models Covered include; 


Chemical Resistance
The chemical resistance of Duramax varies as a function of the particular grade involved. Both the raw materials base (polyester or polyether) and the hardness of the grade affect its chemical resistance.
Final result of research and field test within the limits of the conditions of use, this plastic polymer provides great strength and long-lasting.

Resistance to solvents
Contact with solvents frequently causes the material to swell in the case of high temperatures.

Resistance to alcohol
Resistant to Alcohols, except high temperatures.

Resistance to water and neutral aqueous saline solutions
At normal temperatures, Duramax can remain in contact with water (including sea-water) for many years without experiencing any essential changes in its mechanical properties. Higher water temperatures cause a reduction in strength, and temperatures in excess of 60 °C lead to progressive hydrolytic degradation in ester grades. Ether types swell in hot water. The resultant properties then remain constant for a long period of time.

Resistance to fuels
The resistance of Duramax to fuels is determined by the composition of the fuel involved. Duramax displays good resistance when in contact with fuels of a primarily aliphatic nature – such as standard petrol, diesel oil and kerosene. In the case of fuels that contain alcohol, damage can occur after a prolonged period of contact. Aromatic fuels, such as premium-grade petrol, cause reversible swelling in Duramax. The extent of the swelling correlates with the content and nature of the aromatic ingredients that they contain.

Resistance to oils and greases
Duramax is particularly resistant to pure mineral oils (lubricating oils) and water-free greases. Specially modified high-performance lubricants may be incompatible with Duramax (either the lubricants themselves or their additives), particularly at high temperatures. It is recommended that the effect on mechanical properties and the swelling behaviour be checked before lubricants of this type are applied.

Main benefits:
> Mean mechanical strength
> Great resistance to wear conditions
> Flexibility within a wide range of temperatures
> High elasticity
> Good stability to oils, greases and solvents
> Resistance to weather conditions