The Union Tech Z-Series Valves comprise of both severe-service metal-seated and rising-stem ball valves.  The Z-Series product line covers both zero-leakage critical isolation applications, as well as high performance frequent cycling with positive shutoff applications.


engineering and design

With over 100 years of aggregate product experience, the Z-Series Valves are jointly developed by our team of engineers and seasoned valve experts.  Union Tech utilizes advanced engineering techniques, such as finite element analysis (FEA) and comprehensive flow analysis and combines it with pragmatic "know-how" drawn from decades of product experience to ensure that every valve is optimized for its intended application.  Our engineering team is always available for support with upfront materials selection, piping and instrumentation diagrams (P&ID), and general onsite operations.


integrated manufacturing and service

Every substantial component is machined internally; all critical processes are performed in-house.  This unique approach enables us to maintain and ensure quality and consistency, shorten the supply chain to achieve aggressive delivery horizons, and leverage efficiencies across the entire production process to deliver value to our customers.  Examples of insourced processes include:

  • Engineering and Design
  • Machining
  • HVOF Coating
  • Welding
  • Mate Lapping
  • Assembly
  • Testing per ANSI FCI 70.2 Class VI (or MSS-SP61, API-598, API-607, API-608, API-6D, etc.)
  • In-Field Service and Repair

We do not utilize statistical process control (SPC) for valve testing.  Every single Z-Series valve is tested at completion, and Union Tech furnishes MTR's and individual test reports for each valve.

Z-Series valves are fully customizable and fit for purpose to each specific application.


Z1 Unibody Power Valve

The Z1 Unibody Power Valve is a one-piece metal-seated ball valve engineered for clean steam severe-service (high-pressure, high-temperature) environments, including power generation and critical on/off applications.

  • 0.65" to 3.00" Bore sizes
  • 0.75" to 2.50" NPS SWE; 0.75" to 4.00" NPS BWE
  • 150 to 4500# ANSI classes
  • Design meets ASME TDP-1 2006 bore requirements
  • Materials: A105, F22, F91, and 316SS

Z1-LW Lightweight unibody power valve

The Z1-LW is a one-piece lightweight ball valve designed for clean steam severe-service (high-pressure, high-temperature) environments.  With one integral SW end, the compact design of the Z1-LW valve weighs 50% less than typical flanged valves of the same pressure class.

  • 0.65" to 1.00" Bore sizes
  • 0.75" to 1.00" NPS SWE
  • 150 to 1500# ANSI classes
  • Materials: A105, F22, F91, and 316SS

Z2 two-piece isolation valve

The Z2 is a two-piece metal-seated ball valve engineered for severe-service environments for use in critical applications, including chemical / petro-chemical, refining, power, and mining.

  • 0.50" to 24.00" NPS
  • 150 to 2500# ANSI classes
  • Full and reduced ports
  • Uni or bi-directional seals
  • Material: A105, F22, F91, 316SS, and exotics
  • Firesafe design meets API 607 or API 6FA
  • SIL-3 certification, per IEC 61508:7 2010

Z3 double block and bleed valve

The Z3 Double Block and Bleed Valve is a three-piece, metal-seated valve that provides two isolation points for zero leakage and maintains an upstream and downstream seal under variable and balanced pressure conditions.

  • 0.65" to 3.00" Bore sizes
  • 0.50" to 4.00" NPS SWE
  • 150 to 1500# ANSI classes
  • Material: A105, F22, F91, 316SS, and exotics

z4 rising stem ball valve

The Z4 Rising Stem Ball Valve employs a tilt-and-turn design enabling frequent cycling, zero-leakage, and low torque operation.  This valve is engineered to replace traditional ball, gate, and plug valves in gas processing plants using molecular sieve systems for switching service, pipelines, gas transmission, and other high performance applications requiring frequent cycling with positive shutoff operation.

  • 2.00" to 12.00" Bore sizes
  • 150 to 1500# ANSI classes
  • Bonnet: Enclosed (soft seated) or OS&Y (metal seated)