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G-BLOK® Valves

AFF, as part of the Galperti Group, manufactures the G-Blok® Double Block & Bleed (DBB) valves, specifically designed to provide precision isolation to sections of pipelines, process systems, and instrumentation to safeguard your operations and guarantee efficiency. 

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Galperti Engineering G-Blok® range of standard and special valves includes double block and bleed valves, API valves and slimline compact monoflanges.

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Specific for oil and gas, petrochemical and power generation industry, G-Blok® valves are custom designed to fulfill project applications and specifications: for pipeline or instrumentation, topside or subsea/deep sea, high or low temperature, corrosive or hazardous fluids.​

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G-Blok® DBB/SBB Valves (Ball, Needle, Gate) Sizes up to 2”
Applications

  • Instrument Single/Double Block and bleed for chemical injection and sampling.

  • Instrument Single/Double Block and bleed for pressure connections.

  • In-line Modular Single/Double Block and bleed for process isolation.

Valve Design

  • Floating Ball

  • Trunnion Mounted Ball

  • Wedge Gate

  • Monoflange Needle

  • Root Needle

Size

  • NPS ½ to NPS 2

  • DN 15 to DN 50​​

Rating

  • Up to ASME 4500

  • Up to API 15,000psi

Technical Features

  • Pressure containing components made by solid forged materials.

  • Soft or Metal-to-Metal configuration.

  • Fire-Safe design or certification.

  • Anti-static design.

  • Optimised face to face dimension.

  • Engineered, manufactured, tested and optimised for your specific application.
     

AFF Integral DBB Ball Valve

G-Blok® DBB/SBB Valves (Ball, Needle, Gate) Sizes over 2”
Applications

  • In-line Modular Single/Double Block and Bleed for process isolation.

  • Best design option in offshore environment to reduce weight, space requirements and leak paths by integrating as many valves as possible into a single product.

Valve Design

  • Side-Entry Trunnion Mounted Ball

  • Top-Entry Trunnion Mounted Ball

Size

  • NPS 2½ to NPS 24

  • DN 65 to DN 600

Rating

  • Up to ASME 4500

  • Up to API 15,000psi

Technical Features

  • Pressure containing components made by solid forged materials.

  • Soft or Metal-to-Metal configuration.

  • Fire-Safe design or certification.

  • Anti-static design.

  • Optimised face to face, compact overall dimensions.

  • Engineered, manufactured, tested and optimised for your specific application.
     

Side Entry Trunnion Ball Valve

G-Blok® Ball Valves 
Applications

  • Upstream Operations: Wellhead Isolation and Christmas Tree Assemblies

  • Midstream Operations: Pipeline Transportation and Gas Processing Plants

  • Downstream Operations: Refineries and Petrochemical Plants

  • Storage and Distribution Facilities

Valve Design

  • Side-Entry Trunnion Mounted Ball

  • Top-Entry Trunnion Mounted Ball

  • Side-Entry Floating Ball

Size

  • NPS 2½ to NPS 48

  • DN 65 to DN 1200

Rating

  • Up to ASME 4500

  • Up to API 15,000psi

Technical Features

  • Pressure containing components made by solid forged materials.

  • Soft or Metal-to-Metal configuration.

  • Fire-Safe design or certification.

  • Anti-static design.

  • Robust construction, quick and easy operation with low maintenance requirements.

  • Engineered, manufactured, tested and optimised for your specific application.
     

Side Entry Trunnion Ball Valve

Subsea Valves and Actuators
Applications

  • Permanent subsea

  • Temporary subsea

  • Corrosive services

  • Deep water

  • Rapid cycling operating conditions over extended periods of time

  • Severe conditions with no routine maintenance requirements

Valve Design

  • Manual or Actuated Side-Entry Ball

  • Manual or Actuated Top-Entry Ball

  • Manual or Actuated DB/DBB Side-Entry Ball

  • Manual or Actuated DB/DBB Top-Entry Ball

  • DB/DBB Monoflange Needle

Size

  • NPS ½ to NPS 48

  • DN 15 to DN 1200

Rating

  • Up to ASME 4500

  • Up to API 15,000psi

  • Pressure containing components made by solid forged materials.

  • Design according to API 6DSS, 17D or 6A.

  • Full inhouse testing capacity for valves, hydraulic actuators and gears (quarter turns and linear): hyperbaric chamber, test benches, HPU and ROV tools.

  • Design DNV-RP-F112 with in-house FEM verification.

  • Full customisation for all test ports, scraper rings, high visibility letters and relief systems.

  • Engineered, manufactured, tested and optimised for your specific application.
     

Actuated Subsea Ball Valves
Technical Features

G-Blok® HT – High-Temperature Isolation Valves
Applications

  • Oil & Gas: Volatile hydrocarbons, viscous fluids, aggressive liquids

  • Chemical Processing: Hazardous chemicals, acids, caustics

  • Power Generation: Superheated steam, molten salts, peak shaving

  • Specialty Services: Hydrogen isolation, delayed coking, catalyst cracking

Seal Technology

  • Chrome carbide-coated ballseat
    surfaces

  • Metal-to-metal configuration for low fugitive emissions

  • Spring-loaded upstream seat for cavity protection

  • High-performance graphite packing with live loading

Size

  • NPS ½ to NPS 24

  • DN 15 to DN 300

Rating

  • ASME 150 to 4500

  • Pressure containing components made by solid forged materials.

  • Double seal configuration for all leak paths.
    Primary static seals metal to metal type - Galperti metal self energised seal ring GCCP type, Xylan 1070 coated. 
    Secondary seals - graphite die formed rings.

  • Redundant anti-static devices with all anti-static springs with base material UNS S31603, low stress design.

  • Lip seals and V-packs with UNS S31603 springs
    Seat leak test and fugitive emission test available in-house with blend of nitrogen (95%) and hydrogen (5%).

  • Engineered, manufactured, tested and optimised for your specific application.
     

Hydrogen Service Valve
Technical Features

G-BlokH2 – Valves for Hydrogen Service
Applications

  • High pressure hydrogen storage

  • Medium/Low pressure hydrogen storage

  • Hydrogen transportation

  • Hydrogen distribution

  • Normal temperature electrolysis skids

Valve Design

  • Side-Entry Trunnion Ball

  • Side-Entry Floating Ball

  • Electrolysis Side-Entry Floating Ball

Size

  • NPS ½ to NPS 12

  • DN 15 to DN 300

Rating

  • Up to ASME 2500

Technical Features

  • Floating ball design for reliable isolation and positive shut-off.

  • Robust sealing technology for tight shut-off in extreme operating environments.

  • Engineered for high-temperature, high-pressure and corrosive service conditions.

  • Temperature range: up to 899°C (1650°F).

  • Materials: available in all steel types and nickel alloys to suit process and media requirements.

  • Suitable for demanding, continuous industrial process applications.

  • Built to exceed applicable industry standards for safety and reliability.

  • Optimised for reduced maintenance and extended service life in harsh conditions.

  • Actuation: manual or powered actuation options available (including integration with control systems).
     

Hydrogen Service Valve

G-Blok® Carbon Capture and Storage (CCS) Valves

Engineered for risk-free decompression in sCOâ‚‚ applications

 

G-Blok® CCS valves are purpose-built for carbon capture and storage, handling supercritical COâ‚‚ decompression, low temperatures and impurities. With three confidence levels - Core, Middle-End and High-End - they provide predictable containment and reliable shut-off under pressure/temperature shocks, while avoiding unnecessary over-specification of the wider system.

HIGH-END valves for sCO2 resilience under high rapid decompression

G-Blok® High-End product line for CCS​

  • Valve design optimised for sCOâ‚‚ resilience for planned or unplanned ultra-high-rate decompression and rapid cooling.

  • Stem secondary sealing: high-performance, low emission graphite packing.

  • Static leak paths secured by self-energising metal seal rings.

  • Standard high-capacity emergency seat and stem sealant injector.
     

High End Valve
MIDDLE-END valves with improved design for sCO2

G-Blok® Middle-End product line for CCS​​

  • Valve design for enhanced durability and reliability in sCOâ‚‚ services with standard decompression rates.

  • Additional COâ‚‚ safety factor applied to the extension wall thickness and bolting.

  • No elastomers used.

  • Critical service, self-relieving, and self-energised stem sealing (V-pack).
     

Middle End Valve
CORE valves with sCO2 qualified materials

G-Blok® Core product line for CCS​​

  • Optimised valve design for low-pressure services or applications with moderate decompression rates.

  • Seat insert selection for sCOâ‚‚ mixture compatibility.

  • Non-metallic materials qualified to NORSOK M-710 for 100% COâ‚‚ service.

  • Elastomers certified to NACE TM0297 for rapid gas decompression in COâ‚‚ service.
     

Core Valve
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