LESER Series 800 - Pilot Operated Safety Valve UK

LESER Series 800 – Pilot Operated Safety Valve

The LESER Series 800 is a pilot-operated safety valve engineered for applications requiring minimal pressure differential between set and closing points or for systems with high back pressure. Optimised for oil and gas production, refining, and gas distribution, it delivers precise overpressure protection in demanding environments.

The LESER Series 800 allows seamless interchangeability between Pop Action and Modulate Action pilot valves without the need for tubing modifications. This design simplifies upgrades, reduces spare parts inventory, and enables easy conversion between valve types for enhanced operational flexibility.

Product Benefits

Full Bore Design – Maximises flow capacity relative to nominal size, ensuring optimal performance in high-demand applications.
Integrated Internal Tubing – Eliminates external leakage risks and prevents freezing, enhancing reliability in extreme conditions.
Standard Backflow Preventer – Reduces costs and simplifies procurement while improving system safety and efficiency.

Technical Data

Series 810 - Pop Action Designed for gas applications requiring rapid opening, these valves achieve certified discharge capacity quickly. They feature an adjustable blowdown of 3–7% of set pressure (ASME VIII compliant), extendable up to 15% beyond API standards for enhanced flexibility.

Series 820 - Modulate Action Minimises medium loss by proportionally discharging flow to prevent pressure increases, ideal for applications avoiding atmospheric discharge.

API 526 Compliance – Standardised valve sizes, dimensions, and capacities ensure seamless interchangeability in API-compliant plants.
Versatile Product Range – Available in sizes from 1″ to 8″, with orifices D to T and pressure ratings up to Class 2500 for broad application compatibility.
Optimised Sizing – Additional orifices enable the use of a smaller valve size for a given orifice letter or capacity, enhancing efficiency.
Global Flange Compatibility – ASME, EN, and JIS flange options ensure worldwide applicability and ease of integration.
Integrated Tubing Design – Internal tubing between the main valve and pilot valve is housed within the top plate, preventing leaks and simplifying installation.
Single Trim Design – A unified spring and trim configuration supports both gas and liquid applications, minimizing spare part requirements and maintenance costs.
Material Availability – Standard body materials include WCB, CF8M, LCB, 1.0619, and 1.4408, with additional materials available upon request.
High Back Pressure Tolerance – Back pressure-independent design withstands up to 70% of set pressure in most applications, ensuring reliable operation.
Flexible Sealing Options – Choice of metal or O-ring discs accommodates a wide range of process conditions.
NACE Compliance – Corrosion-resistant materials meet NACE standards with minimal component replacement, enabling fast delivery.
Standard Backflow Preventer – Enhances system protection and reduces ordering complexity.
Top-Loader Design – The single-piece valve seat allows for easy in-place maintenance without removing the entire POSV.
Modulate Action Options – The Series 820 is available in diaphragm or piston designs, tailored to different operating pressure ranges.

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