Frenstar Valves

Valve Manufacturer, Stockist & Project Solution Specialist

Trunnion Mounted Ball Valves

The Frenstar range of high quality metal & soft seated trunnion ball valves are designed for many applications in the oil and gas, petrochemical, power & general process industries. 

The trunnion design employs a ball, with two trunnions, affixed to the ball at the top and bottom. The unit fits into a space in the valve body and cannot move along the flow axis.

Trunnion ball valves are suited to high pressure or larger size valves with lower operational torque and long durability.

The trunnion ball valve is generally used in these applications:

  • Oil & Gas
  • High-temperature services
  • High-pressure services
  • High-cycle and switching services
  • Emergency shutdown valves
  • High-integrity pressure protection system
  • Gasification


  • Metal Seated – FMT Metal seated trunnion ball valves
  • Soft Seated – FST Soft seated trunnion ball valves


(Fire safe API607, API6Fa)

Anti blow‐out stem /Anti Static design

Two Piece Body or Three Piece Body  / Split Body

Side or top entry / Full bore and Reduced bore / Fugitive emission 


API6D, API598, API6A / ASME B16.34, B16.5, B16.10 / MSS-SP-55

Size Range

NPS 2” – 48”  

Pressure range

ANSI 150 – 2500#

End Connections

Flanged /Butt Weld/Socket Weld/Threaded/Hub

Body Seat

Metal  / Graphite, Devlon, TFM, PTFE, RPTFE, PEEK, POM, PCTFE, Nylon


Lever / Gear / Actuator (pneumatic – electric – hydraulic)

Materials of Construction


Nickel Alloys (Monel®, Inconel®, Hastelloy®, Incoloy®), Duplex and Super Duplex, Carbon Steel and Low Temp Carbon Steel, Low Alloy Steel, Stainless Steel, Titanium, Zirconium and other exotics upon request

Ball Valves

Frenstar offer a wide range of Ball Valves from our dedicated factory to the finest quality for use within various industries. Our range includes:

  • Floating or Trunnion Mounted
  • Double Block and Bleed
  • Multiport 3-way ball valves
  • Soft or Metal Seated
  • Fire safe certified
  • Cryogenic service


Size Range1/2″ – 56″ (DN15 – DN1400)
Manufacturing StandardAPI 6D, EN-17292, NACE MR 01 75
Pressure ClassASME CLASS 150 to 2500
DIN-PN PN 10 to 64
API 3000 to 10000
Materials of ConstructionCarbon & low alloy Steels
Stainless steels
Duplex & Super Duplex
Nickel Alloys

Why use a Ball Valve?

Ball valves usually function as block valves to fully shut off or fully open flow. They are suitable for conditions where on/off and/or bubble-tight service are required.

Frequently Asked Questions

What are ball valves used for?

Ball valves usually function as block valves to fully shut off or fully open flow. Ball valves are suited for conditions where on/off and/or bubble-tight service are required.

Can ball valves be used for isolation?

Ball valves are widely used for isolation purposes as they can attain positive shut off due to the soft seats. 

What is the difference between ball valve and gate valve?

Ball and gate valves both function to block flow, gate is most commonly used however ball is a better choice for some particular applications. They have significant physical differences. Gate valves open by lifting a gate out of the path of the service fluid, ball valves have a stem and a ball that turn horizontally. 

Can ball valves be used for throttling?

Soft-seal ball valves are not normally used for throttling service because the valve seats are subject to erosion or displacement when the valve is not fully open or fully closed.

What is a trunnion mounted ball valve?

The trunnion ball valve is a quarter-turn valve which uses a hollow, fixed ball to control flow.

What is a floating ball valve?

In a floating ball valve, the ball is held in the position by the compression of the two elastomeric seats against the ball. The ball is free to float inside the valve body.