In-house manufacturing

Our highly qualified staff takes care of each single seat, from ½” up to 60”, as a unique piece during the complete manufacturing process. Our engineers design them and our skilled workers produce them and marked them. A.V.V. preliminary analyze with Customer: application, media, temperature, pressure and leakage rate and recommend the solution that most suit to request according to our experience and innovative solution.

From ½” up to 60”

Product design


As a manufacturer of components for trunnion ball valves for oil and gas application, we offer an extensive range of sealing solutions and materials, to meet all the valve application and most customer requirements.

Thanks to our experience and our material database we are able to provide to our customers solutions suitable to any condition according their requirements.
During the preliminary phase we can cooperate with you to co-designing and proposing our devices, improvements or a totally new design.


We supervise the process from beginning: starting from strict control during all machining phases go ahead with a stringent control on sphericity and circularity, passing through blue pigment test, a lapping phase and finalizing with a 100% bubble tight on alcohol test. Hardness, density, adhesion, thickness and corrosion test are required as standard for the qualification of the superficial treatment.

Product design


We specialize in in-house manufacturing, to ensure control is maintained throughout the production process, delivering best quality products that perform in service.
All aspects of our design and production process comply with the ISO 9001: 2015 quality system.

Quality means providing exactly what our customers need in terms of product, delivery and price.

Our product range


ST - Soft insert seats

Soft insert consists in a thermoplastic ring locked into the metal seat.

The selection of the thermoplastic material depends on the application (pressure, temperature, type of fluid, etc.).

Thermoplastics insert can be selected among a wide range of material, to match the chemical and mechanical properties with specific working environment of the valve.

Based on our experience, different material and Valve characteristics requires different kind of groove’s technology and thermoplastics shaping in order to guarantee best performance and a longer component life.

The process of insertion and machining is guided by strict rules in order to assure the sealing functionality and the component integrity.

SD - Delta protector seat

Delta-Protector is a design which allows to have two different kinds of sealing: thermoplastic and elastomeric.

This design is suitable for many applications and it guarantees a zero-leakage condition without further matching or lapping. This sealing can avoid problems due to circularity/sphericity errors or high level of roughness of the ball.

The delta ring works at very low pressure ensuring “zero-leakage” with rubber sealing.

The thermoplastic ring protects the soft delta ring in high pressure condition. In higher class valves the thermoplastic ring can provide a secondary sealing and testing condition similar to a thermoplastic design.

Specials testing and assembling procedures were created in order to guarantee longest life of the kit.

SM – Metal to metal seats

Metal-to-metal seats are specific for abrasive media or high temperature service.

in this kind of seat design, frontal sealing is hard (metal) and this feature is required when the normal soft sealing is no longer suitable due to the unfavourable combination of pressure, temperature and chemical composition of the medium, when solid particles are present, when operating conditions prevails on the need of the fully tight sealing.

Seat rings are hard faced using different coating material such as Electroless Nickel, Chrome Carbide, Tungsten Carbide.

for this design, final matching between seats and ball are strict recommended and they guarantee an accurate finishing 0,02 Ra, that means the ideal sealing of the kit.

for this reason, to assure high quality level, we usually supply the complete kit ball and seats, matched and tested.

SE – Triple sealing seats

Triple sealing design allows to have three different kind of sealings: thermoplastic, elastomeric and metal sealing.

Triple sealing is suitable for many applications, in particular for critical condition and for gas application, it guarantee perfect sealing.

The delta ring works at very low pressure ensuring “zero leakeage” as rubber sealing. Thermoplastic insert protects the soft sealing and in the meantime is a seat at full pressure rate; the metal area guarantees the sealing protecting the wearing and scraping.

This patented design allows the best performance in term of max working pressure and durability.


SF – Floating seat

A.V.V. produces seats for floating ball valve in different designs: Thermoplastic elastic

seats in different materials according to the valve application.

Standard application is PTFE (up to class 300), filled nylon (up to class 900) and Peek (higher class).

Metal seat with thermoplastic insert according to the customer specification and spring on the back side.

Metal to metal seat with TCC and stainless-steel reinforced graphite on the back side

Radial sealing is a sensitive sealing point in a ball valve. Back side seat sealing could be supplied in different design according to temperature, pressure and media.

We manage the best solution proposing the right combination between:

  • O-ring
  • Backup
  • Lip seal
  • Graphite and fire safe gaskets
  • Chevron packing
  • Springs


BT – Trunnion ball

Standard design for standard application as gas or oil transmission

The ball can only turn around its own axe (trunnion axe) and sealing is guaranteed by the axial movement of the seats for springs or inline pressure.

The trunnion design is suggested for medium and big dimensions and enables to avoid high torque during opening or closing phase with inline pressure.

Trunnion ball guarantees an easy assembling into valve, a wide surface for washers (reducing friction and torque).

The ball is in direct touch with the valve body through ball support.

BI – Inner trunnion ball

This type with inner trunnion guarantees a stronger resistance of the ball than the outer, and so less deformation in high pressure condition reducing the risk of leakage between ball and seats.

For dimensions lower than 6” inner trunnion is the only possible solution due to the dimension.

This kind of design guarantees a strong product because it’s hard-to-deformed by pressure.

It is suitable for small dimensions and for metal-to-metal application.

BE – outer trunnion ball

The ball with trunnion out of spherical surface guarantees the maximum rigidity of the system compared with other designs.

This design assures high performance in terms of mechanical properties and long-life application.

Manufacturing of this product required a very skilfully due to the special geometry and the strict dimensional tolerance, mainly as regards the two outer trunnions, in order to ensure the correct alignment of the ball inside the valve.

This kind of ball design is suitable for special metal to metal application, especially for subsea, and for high rate (2500).

BF – Floating ball

In floating valve the ball floats axially due to pressure granting the sealing with seat downstream (close position).

Floating balls are designed for small sizes (maximum up to 6”).

A.V.V. provides finished balls according to customer drawings.