Globe Valve Actuation

Globe valves can be actuated pneumatically, electrically, manually, or hydraulically. The choice of actuation method significantly influences the valve's performance, affecting factors such as flow control, precision, response time, and overall system efficiency. This article explores the main features of manual and automatic globe valves.

Table of contents

• Globe valve features
• Globe valves with pneumatic actuators
• Electric actuated globe valves
• Manual globe valves
• Hydraulic globe valves
• Comparison of globe valve actuation types

Globe valve features

Actuated globe valves are designed for throttling and controlling flow in a pipeline. The valve actuation can be manual or automated. The features of actuated globe valves include:

• 2-way/3-way: Globe valves are available in 2-way or 3-way configurations. 2-way globe valves are used for simple shutoff tasks and 3-way valves are designed to either divert or mix fluid flow, catering to the specific needs of various applications.
• Suitable for harsh environments: The valve is made with corrosion resistant materials like stainless steel or brass housing with PTFE/EPDM sealing making it highly resistant to corrosion and suitable for use with corrosive media and in harsh environments.
• Customizable: Can be fitted with accessories for position feedback, manual override, and stroke limitation for enhanced control and monitoring.
• Flow direction flexibility: Globe valves can operate with flow either above or below the seat, providing flexibility in installation and use. The valve seat's alignment with the flow enhances throttling and minimizes wear on the disc and seat.
• High flow capacity: Designed to accommodate high flow rates, making them suitable for demanding applications where flow control is critical.
• Certifications: Available with ATEX, IECEx, DVGW, and food approval standards, ensuring suitability for a wide range of environments.
• Versatility: With options for customization and various certifications, these valves are adaptable to explosive atmospheres, gas systems, and the food industry. Specific models are capable for CIP and SIP operations, making them suitable for sanitary applications.

Globe valves with pneumatic actuators

Pneumatic globe control valves are operated by pneumatic actuators. These actuators use compressed air to generate the force needed to move the valve stem and the attached disk or plug towards or away from the valve seat.

Key features

• Speed: Pneumatic actuators offer quick operation, making them suitable for scenarios where time is critical.
• Compressed air requirement: These systems need a reliable source of compressed air, which involves air compressors and treatment systems.
• Environmental suitability: They perform well in harsh conditions due to the robustness of pneumatic components and corrosion-resistant materials.

Electric actuated globe valves

An electric globe valve's electric actuator is a motor-driven device that opens or closes the valve based on electrical signals. In addition to traditional electric actuators, solenoid-operated globe valves offer a compact and efficient solution for applications requiring rapid and frequent opening and closing. Electrically actuated globe valves are designed to offer superior control over fluid flow in various applications, from HVAC systems to industrial processes and water treatment facilities.

Key features

• Remote operability: Allows for the valve to be operated remotely, enhancing operational flexibility and safety.
• Precision: Electric actuators provide accurate control over the valve position, suitable for precise flow regulation.
• Flexibility: Electric actuators can be programmed with various control modes (on/off, proportional, modulating) to adapt to different flow requirements and system dynamics.
• Power dependency: These systems rely on electrical power, which could be a limitation in areas with unreliable power supply.

Manual globe valves

Manual globe valves are operated manually through a handle or a lever. They do not require external power sources or compressed air for operation. They are mostly used in the chemical, petrochemical, and pharmaceutical sectors.

Key features

• Direct control: Offers tactile feedback and allows for precise adjustments without the need for external power.
• Simplicity and reliability: With fewer moving parts and no reliance on external power sources, manual valves are straightforward and dependable.
• Physical presence required: The main limitation is the need for an operator to be physically present to adjust or operate the valve.
• Limited automation: Not suitable for automated control systems or remote operation.

Hydraulic globe valves

Hydraulic globe control valves are operated by hydraulic actuators. These actuators utilize pressurized hydraulic fluid to generate the force necessary to move the valve stem and the attached disk or plug towards or away from the valve seat. Hydraulic globe valves are employed for precise throttling and flow control in various sectors, including oil and gas, petrochemicals, and heavy machinery manufacturing.

Key features

• High force: Hydraulic actuators can generate significant force, making them suitable for moving large valves under high pressure.
• Fluid power: Utilizes pressurized fluid to actuate the valve, requiring a pump and fluid reservoir.
• Precision and control: Offers precise control over valve positioning, similar to pneumatic and electric actuators but with the added benefit of higher force output.

Comparison of globe valve actuation types

Table 1: Comparison of globe valve actuator types

Actuation type	Power source	Speed	Pros	Cons	Best for applications
Pneumatic	Compressed air	Fast	Fast response time, robust, cost-effective for certain sizes	Requires compressed air source, not as precise as electric actuators	Oil and gas industries, power plants, situations requiring fast action
Electric	Electric motor	Moderate to fast	Precise control, Remote operation capability,available for a wide range of voltages	Requires electric power source, can be more complex and expensive	HVAC system, water treatment plants, remote or automated control systems
Manual	Human effort (handwheel or gear)	Slow	Simple and reliable, no external power required	Not suitable for remote control, can be physically demanding	Low duty cycles, accessible location, small sizes or low-pressure systems
Hydraulic	Pressurized fluid	Moderate to fast	Very powerful, suitable for large valves,	Requires hydraulic fluid source, more complex system with higher maintenance	Heavy industry, high-pressure applications, and large valve operations