Fisher 657 vs 667 Actuators: Differences and Surplus Values
For over 30 years, I’ve specialized in buying and selling Fisher actuators, and two models that frequently come up in industrial surplus markets are the Fisher 657 and 667 actuators. If you’re navigating the complex world of valve automation equipment, understanding the Fisher 657 vs 667 actuators: differences and surplus values is essential for making informed purchasing or selling decisions. In this comprehensive post, I’ll break down the technical distinctions, operational capabilities, common applications, and market value considerations of both actuator models to help you maximize your surplus inventory or procurement strategies.
Overview of Fisher Actuators
Fisher, a brand under Emerson Automation Solutions, has been a leader in valve automation for decades, providing reliable actuators designed for industrial control valves utilized in oil & gas, chemical processing, power generation, and water treatment industries. The 657 and 667 actuators both belong to Fisher’s pneumatic rotary actuator lineup, designed to convert air pressure into torque for quarter-turn valve operation. However, they have unique features and design differences that impact performance and price in the surplus market.
Technical Comparison: Fisher 657 vs 667 Actuators
| Feature | Fisher 657 | Fisher 667 |
|---|---|---|
| Type | Double-acting pneumatic rotary actuator | Double-acting pneumatic rotary actuator |
| Operating Torque Range | Up to 5,000 in-lbs (approx. 565 Nm) | Up to 8,000 in-lbs (approx. 904 Nm) |
| Pressure Range | 20 to 125 psi (1.38 to 8.62 bar) | 20 to 150 psi (1.38 to 10.34 bar) |
| Rotation Angle | 90° ± 5° | 90° ± 5° |
| Materials | Aluminum body, stainless steel shafts, Buna-N seals | Cast aluminum body, stainless steel shafts, Viton seals for high temp |
| Temperature Range | -20°F to 180°F (-29°C to 82°C) | -40°F to 250°F (-40°C to 121°C) |
| Weight | Approx. 12 lbs (5.4 kg) | Approx. 15 lbs (6.8 kg) |
Operating Torque and Pressure Differences
The Fisher 667 actuator offers a higher maximum torque output, approximately 8,000 in-lbs compared to the 657’s 5,000 in-lbs rating. This makes the 667 more suitable for larger or more demanding valve applications requiring greater force to actuate. Additionally, the 667 supports pressures up to 150 psi, whereas the 657 is limited to 125 psi. This extra pressure margin allows for faster actuation speeds and improved reliability in tougher operational environments.
Materials and Temperature Ratings
Both actuators incorporate aluminum bodies and stainless steel shafts for corrosion resistance. However, the 667’s use of Viton seals expands its effective temperature range significantly, from -40°F to 250°F, making it preferable for higher temperature processes such as steam or hot oil applications. The 657, with Buna-N seals, is better suited for moderate temperature environments.
Application Considerations
Choosing between Fisher 657 vs 667 actuators depends on your valve size, torque requirements, environmental conditions, and process specifications. Here are typical applications for each:
- Fisher 657: Small to medium quarter-turn valves such as butterfly and ball valves in water treatment, compressed air systems, and HVAC controls with moderate torque and temperature needs.
- Fisher 667: Larger valves requiring high torque, including industrial chemical reactors, pipeline isolation valves, and steam service where higher pressure and temperature ratings are crucial.
Surplus Market Values and Selling Advice
From my extensive experience at Industrial Surplus World, the value of surplus Fisher actuators depends heavily on condition, model demand, and included accessories like positioners or limit switches.
Typical Surplus Values (As of 2024)
- Fisher 657: Used units in good working condition typically range from $750 to $1,200 per actuator.
- Fisher 667: Due to higher torque and temperature capabilities, used 667 actuators command a premium, generally between $1,200 and $1,800.
New surplus units or factory overstock can be priced significantly higher, reflecting original list prices between $2,500 and $3,800 depending on configuration.
Maximizing Surplus Value
To get the best return on your surplus Fisher 657 or 667 actuators:
- Provide detailed specs and inspection reports: Include torque ratings, pressure capabilities, and any recent maintenance or testing documentation.
- Include accessories: Units with mounted positioners (like Fisher DVC6200 series) or limit switch kits typically sell faster and for higher prices.
- Clean and test the units: Actuators free of corrosion, leaks, or mechanical defects attract premium buyers.
- Know the market: Larger process facilities and industrial integrators are the primary buyers for surplus Fisher actuators; targeting these groups can yield better offers.
Industry Standards and Specifications
Both Fisher actuators meet industry standards such as ISA (International Society of Automation) standards for pneumatic actuator performance and comply with API (American Petroleum Institute) guidelines for valve automation where applicable. Their precision machining and material certifications (e.g., ASTM B209 for aluminum alloys) ensure reliability in harsh environments.
Five Frequently Asked Questions About Fisher 657 vs 667 Actuators
- What are the key mechanical differences between the Fisher 657 and 667?
The 667 features a higher maximum torque rating (up to 8,000 in-lbs vs 5,000 in-lbs for the 657), a wider operating pressure range (up to 150 psi), and enhanced temperature capabilities due to Viton seals. The 657 is lighter and suited for moderate duty cycles, while the 667 is built for high-demand applications. - Can I retrofit a Fisher 657 actuator with parts from a 667?
Generally, no. While both are pneumatic rotary actuators, their internal components, shaft dimensions, and torque ratings differ. Retrofitting would likely require significant modifications and is not recommended without engineering validation. - How do surplus prices vary by actuator condition?
New surplus or factory overstock units command near-list prices ($2,500-$3,800). Used units in excellent condition sell for $750-$1,800 depending on model and accessories. Units needing repair or missing parts drop below $500. - Which actuator is better for high-temperature steam service?
The Fisher 667 is preferable due to its Viton seals and wider temperature rating (-40°F to 250°F). The 657’s Buna-N seals limit it to about 180°F. - Where can I find official Fisher actuator manuals and specs?
Emerson’s official website offers detailed datasheets and maintenance manuals for both models at Fisher Actuators by Emerson.
Internal Resources for Buyers and Sellers
For more information about buying and selling Fisher actuators, visit our homepage or reach out directly via our contact page for personalized assistance. We provide expert appraisals and help source specific models to meet your industrial automation needs.
Conclusion and Expert Advice
Understanding the Fisher 657 vs 667 actuators: differences and surplus values is crucial for anyone involved in the industrial valve automation market. The 667 model offers enhanced torque and temperature capabilities suited for demanding applications, while the 657 is a reliable, cost-effective choice for moderate service conditions. When selling or buying surplus actuators, condition, accessories, and accurate technical documentation drive market value.
Whether you’re looking to liquidate excess inventory or source quality Fisher actuators for your next project, leverage decades of industry expertise to ensure you get the best value. For a detailed consultation on Fisher actuators, call me directly at 954-488-0700. I’ll help you assess your equipment and maximize your investment.