Ball Valves for Gas Networks

What is a Ball Valve?

A ball valve is a high-quality, general service valve designed primarily for gas isolation applications. Renowned for their robust construction and reliability, these valves are suitable for use with under-pressure drilling equipment, making them ideal for gas distribution networks. The Donkin series, such as the Series 455/51 and Series 455/57, are Kitemark™ approved to GIS/V4 standards, ensuring compliance with industry regulations.

How Does a Ball Valve Work?

A ball valve operates using a straightforward mechanism: a spherical ball with a central bore (hole) rotates within the valve body to control the flow of gas. When the bore aligns with the pipeline, gas flows freely; rotating the ball 90 degrees positions the bore perpendicular to the flow, effectively stopping it. This quarter-turn operation allows for quick and reliable isolation of gas flow. The design ensures minimal pressure drop and most Donkin valves provide a full clear bore, facilitating under-pressure drilling operations. Pre-loaded PTFE seats and a maintenance-free compact design contribute to the valve's durability and ease of use. 

Where Are Ball Valves Used?

Ball valves are utilised across various industries and applications, including:

• Gas Distribution Networks: For isolating sections during maintenance or emergencies.
• Industrial Gas Systems: Ensuring safe and efficient control of gas flow in manufacturing processes.
• Under-Pressure Drilling: Allowing for safe tapping into live gas mains without service interruption.
• Residential and Commercial Gas Installations: Providing reliable gas service isolation points for buildings.

Key Features & Benefits of Donkin Ball Valves

• Maintenance-Free Design: Eliminates the need for regular servicing, reducing operational costs.
• Pre-Loaded PTFE Seats: Ensure a tight seal and smooth operation.
• One-Piece Body Construction: Enhances durability and reduces potential leak points.
• High Torque Design: Prevents unauthorised operation, enhancing safety.
• Full Clear Bore: Allows for under-pressure drilling and minimal pressure drop.
• Kitemark™ Approved to GIS/V4 or GIS/V7-2: Meets stringent industry standards for quality and safety.

Donkin Ball Valve Types & Materials

Donkin ball valves are available in various configurations to suit different applications:

• Series 450: A quick operating, general purpose, reduced bore ball valve. ductile iron, with flanged connections and self indicating handle.
• Series 451: Are ductile iron, reduced bore ball valves with a choice of connections - flanged, screwed both ends, spigot both ends, spigot one end screwed one end.
• Series 455/51: Clear bore, ductile iron ball valve featuring a screwed full-bore design, suitable for general gas isolation.
• Series 455/57: Clear bore, ductile iron ball valve, designed with limited dimensions, female and male thread, for tapping directly into live gas mains, ideal for under-pressure drilling.
• Series 455/74: Purge / bypass point ball valve, ductile iron, clear bore, PE spigot one end / screwed one end, for use on Medium Pressure PE Gas Mains.
• Series 460: A very versatile reduced bore, flanged, cast steel, ball valve. For use with a wide range of gases and fluids including natural and manufactured gases, air, oil, water, and LP steam.
• Certus PE Ball Valves: Constructed from PE100 material, these valves can be welded to PE pipes, creating a fully welded, leak-free system. A valve installation and access is also available.

Choosing the Right Gas Ball Valve

When selecting a ball valve, consider the following criteria:

• Application Requirements: Determine if the valve is for general isolation, under-pressure drilling, or integration into PE pipe systems.
• Size and Pressure Ratings: Ensure the valve's dimensions and pressure capabilities align with your system's specifications.
• Material Compatibility: Choose valve materials that are compatible with the gas type and environmental conditions.
• Compliance and Certifications: Verify that the valve meets relevant industry standards, such as GIS/V4 or GIS/V7-2.

Why Choose AVK UK?

AVK UK is a leading manufacturer of high-quality valves and fittings, with a longstanding reputation for excellence in the gas industry. Our Donkin ball valves are engineered for reliability, safety, and performance, ensuring they meet the rigorous demands of modern gas distribution systems. With comprehensive customer support and a commitment to innovation, AVK UK is your trusted partner for gas valve solutions.

Explore Our Ball Valve Range

Whether you require valves for standard gas isolation or specialised applications like under-pressure drilling, our products are designed to meet your needs. Discover the full range of Donkin Ball Valves by visiting our Product Finder. For expert technical advice contact Jon or, to for a quotation or submit an enquiry, contact our sales team on the contact links below:-

Gas Ball Valve Training and Factory Tours

The AVK Ball Valves are made at Bryan Donkin Ltd in Chesterfield - the home of the gas valve -  and we welcome visitors to come along to the facility for training not only on ball valves but our complete gas valve range if required. You will have a factory tour to see how they are made and 'get hands on'.

Contact our gas expert, Jon Briafield, directly on the link below to arrange your visit. Alternatively we can come you: We can either drive our mobile roadshow van to your site, do group workshop sessions, lunch & learns or even via teams - contact Jon to arrange your training requirements.