VGD20.503 Siemens Gas Valve

Overview

The Siemens VGD20.503 is a 2 inch double-body gas valve designed for integration into gas trains to provide reliable safety shut-off control. As a class A valve conforming to EN 161 standards, it features a normally closed modular design that consists of two safety shut-off valves in series. When combined with Siemens SKP series electro-hydraulic actuators, the VGD20.503 facilitates critical functions such as gas pressure regulation and air-to-gas ratio control for commercial and industrial burner applications. Its robust construction and integrated filtration system ensure long-term durability and protection for downstream components.

Features

• Dual-valve design incorporates two safety shut-off valves within a single compact body for enhanced safety and reduced footprint
• Integrated stainless steel mesh strainer with a 0.9 mm mesh size protects valve seats and downstream equipment from debris
• Specialized valve discs featuring a flat inlet disc for safety shut-off and a contoured outlet disc for precise pressure regulation
• Flexible mounting options with exchangeable pilot gas flanges and universal mounting plates that can be fitted on either side
• High-precision dual stem guides ensure accurate disc alignment and tight, reliable shut-off
• Compatible with a wide range of gases including gas families I, II, III, and air

Specifications

• Model: VGD20.503
• Connection Size: 2 inch (available in NPT or BSP threaded versions)
• Maximum Operating Pressure: 150 kPa (1.5 bar / 20 psi)
• Static Pressure Rating: Up to 1200 mbar when closed
• Flow Capacity: Approximately 100 m3/h
• Permissible Gas Temperature: 14 F to 140 F (-10 C to 60 C)
• Body Material: Die-cast aluminum
• Vent Connection: 3/4 inch or 1 inch NPT/BSP vent port located between valves
• Weight: Approximately 3.2 kg (7.1 lbs)

Applications

• Industrial and commercial gas-fired combustion plants and boilers
• Integration into gas trains for forced draft gas burners
• Safety shut-off combined with pressure regulation when used with SKP25, SKP55, or SKP75 actuators
• Standard safety shut-off service when paired with SKP15 series actuators
• HVAC systems requiring precise air/gas ratio control in high-demand environments