Markets & Applications

Instruments & Controls

Fulton Bellows’ pressure regulators and sensors play a crucial role in instrumentation and control applications. By precisely controlling and monitoring pressure levels, our products enable efficient and accurate operation across various industries.


In industrial settings, our pressure regulators ensure that the pressure of fluids or gases remains within the desired range, preventing equipment damage and ensuring optimal performance. Whether it’s controlling pressure in manufacturing processes, hydraulic systems, or pneumatic applications, our regulators deliver reliable and consistent results.

Complementing our pressure regulators, Fulton Bellows’ pressure sensors offer real-time pressure monitoring, providing valuable data for process control and system optimization. By accurately measuring pressure levels, these sensors enable operators to maintain optimal conditions and respond promptly to any deviations or abnormalities, ultimately enhancing safety and efficiency in critical operations.

In one remarkable aircraft application, Fultons’ bellows play a vital role in protecting load-cell electronics. The bellows act as a flexible cover over the load-cell device, which senses the weight of the aircraft through the landing gear before departure. The bellows’ mission is twofold: to hermetically seal and shield the load-cell electronics from environmental contamination, while remaining flexible to accommodate the dynamic movements of the aircraft.

By providing a robust and flexible seal, our bellows prevent moisture, dust, and other contaminants from compromising the load-cell electronics’ integrity. The hermetic sealing ensures accurate weight sensing and reliable performance, safeguarding critical data for safe aircraft operations.

Basic and Common Applications

Shaft Seal

Prevents leakage around a revolving shaft. Spring pressure holds nose of seal against shoulder on shaft. Another type rotates with shaft and seals against a stationary plate.

Pressure Motors

Convert pressure effects into controlled movement or force. Pressure may be applied inside the bellows or outside the bellows in a cup structure, the latter being preferred. The floating head is usually provided with a limit stop when overload protection is needed.

Flexible Joint

Provides a means to seal a flexible joint or mechanical movement of levers, linkage, etc. against leakage where the movement must be conveyed outside enclosure. “P” optimum position of pivot.

Aneroid Assemblies

An aneroid assembly is a pressure motor where one side of a bellows assembly (inside the assembly illustrated) is evacuated to form a constant reference pressure against which the changing pressure on the other side is measured and used to produce predictable stroke. A spring for rate control and a stop to prevent excessive stroke from the resulting one atmosphere pressure differential usually are required.

Expansion Chamber

This type of assembly is employed to absorb thermal or pressure expansion. With suitable heads, it may be used as a reservoir for a liquid or gas. Examples: Oil reservoir for electrical cable joint and thermal expansion compensators on oil-filled transformers.

Thermostatic Motors

Similar to pressure motors. Pressure supplied by a sealed fill of thermo-sensitive liquid or gas. Thermal effect may be received either on the bellows element direct or at a remote bulb for transmission through flexible tubing. Widely used to operate valves, switches, etc., in response to temperature changes.

Remote Transmission

Two bellows assemblies joined by a tube for hydraulic transmission of motion or power. With bellows system solid filled, linear motion of one bellows is transmitted instantly and in equal degree to remote bellows, both bellows being provided with limit stops when overload protection is needed.

Expansion Joints

Packless and leakless construction is used to absorb thermal expansion of pipe lines carrying steam, water, etc., or, to absorb vibration or provide a flexible connection.

Packless Construction

Diagram illustrates packless valve construction. Same principle is used to seal steam movement or adjustment in many types of apparatus.