Fisher Types 1808 and 1808A | Economical Pilot-Operated Relief and Backpressure Control

Key Benefits and Advantages

• Simple and Reliable Design: The straightforward mechanical architecture minimizes the number of moving parts, leading to high reliability and reduced potential for failure in remote field locations.

• Compact and Lightweight: Their small physical footprint makes them ideal for installation on skid-mounted equipment or in tight piping manifolds where space and weight are critical considerations.

• Installation Versatility: These valves are designed for convenient installation in any orientation, providing engineers with maximum flexibility when designing piping layouts for separators or distribution headers.

• Self-Draining Body: The internal geometry is designed to prevent the accumulation of liquids, which is essential for preventing ice formation or debris buildup that could interfere with valve operation.

• Quick Disassembly: Maintenance is simplified by a design that allows for fast disassembly. This ensures that internal inspections and parts replacement can be completed with minimal downtime.

• Optional Upstream Registration: Can be configured with upstream registration to reduce pressure build-up, ensuring the regulator maintains a tighter control band even during high-flow relief events.

• Media Versatility: Suitable for use in both gas and liquid service, allowing for standardized equipment across different process streams on a single site.

Technical Properties

• Body Styles:

  1. Type 1808: Standard globe-style body for straight-through piping.

  2. Type 1808A: Angle-style body, often used to replace a 90-degree elbow in the piping.

• Operation: Pilot-operated for high sensitivity and rapid response to pressure changes.

• Application: Relief (overpressure protection) or Backpressure (upstream pressure maintenance).

• End Connections: Available in standard NPT threaded connections for easy integration.

• Materials: Typically offered in robust materials suited for oilfield and utility environments.

Field of Application

The 1808 Series is the go-to choice for upstream oil and gas production and local gas distribution networks. Its blend of economy and performance makes it a staple for mid-range pressure applications.

Primary Industries and Uses:

• Oil and Gas Production: Maintaining constant backpressure on separators to ensure efficient liquid and gas phase separation.

• Gas Distribution Systems: Serving as an economical relief valve for local distribution stations to protect downstream assets.

• Compressor Skids: Providing relief protection for bypass lines and suction headers.

• Liquid Gathering Lines: Managing backpressure in liquid lines to prevent surging or cavitation.