MKS 99G1685 Vacuum Isolation Valves

( Brand: Mks ), ( Manufacturer Part Number: 99G1685 ), ( Part Type: Vacuum Valve ), ( Country Of Origin: United States )

Review MKS Vacuum Isolation Valves

The **MKS 99G1685** is a high-performance **vacuum isolation valve** engineered for precision control in demanding industrial, scientific, and research applications where reliability and leak integrity are paramount. Designed with a **pneumatic or manual actuation system**, this valve features a **pneumatic actuator** (optional) that ensures rapid, repeatable, and forceful sealing, making it ideal for systems requiring quick isolation without manual intervention. The valve employs a **metal-sealed construction**, utilizing a **copper or stainless steel sealing interface** to achieve an ultra-low outgassing rate and exceptional vacuum integrity, typically maintaining pressures as low as **10 Torr** in properly configured systems. Its **flanged connection** (with standard CF or ISO-KF compatibility) ensures secure integration into existing vacuum chambers, manifolds, or process lines, while the **3-way or 2-way configuration** provides flexibility for flow redirection or complete isolation as needed.

The **99G1685** is constructed from **304 or 316 stainless steel**, materials chosen for their corrosion resistance, durability, and compatibility with aggressive chemicals, cryogenic temperatures, and high-temperature environments. The valve s **pneumatic actuator** (when installed) operates via a **dual-port design**, allowing for bidirectional control with minimal dead volume, which is critical in applications where residual gas contamination must be minimized. The **sealing mechanism** incorporates a **flexible metal bellows or diaphragm**, reducing the risk of particulate contamination and ensuring long-term reliability even under cyclic operation. For applications requiring manual override, the valve can be equipped with a **lever or handwheel actuator**, providing a failsafe for emergency isolation or maintenance procedures.

Beyond its mechanical robustness, the **MKS 99G1685** is designed with **user convenience in mind**, featuring a **clear status indicator** (such as a position switch or visual marker) to confirm whether the valve is fully open, closed, or in transit. The valve s **low outgassing characteristics** and **compatibility with UHV (ultra-high vacuum) systems** make it a preferred choice for semiconductor fabrication, particle accelerators, mass spectrometry, and other high-precision environments where even trace gas contamination could compromise results. Additionally, its **modular design** allows for easy integration with MKS s broader range of vacuum instrumentation, including pressure gauges, mass spectrometers, and leak detectors, streamlining system control and monitoring.

For applications demanding **high-temperature resistance**, the valve can be specified with **high-temperature seals and gaskets**, ensuring stable performance in environments exceeding **200 C**. The **99G1685** also excels in **cryogenic applications**, maintaining functionality at temperatures as low as **-200 C**, making it suitable for cryopumps, superconducting magnets, and other low-temperature processes. With **standardized mounting flanges** and **compatibility with common vacuum standards**, this valve offers a seamless transition between different system components while upholding the highest standards of leak tightness and operational efficiency. Whether deployed in a **research laboratory, industrial manufacturing facility, or critical infrastructure system**, the **MKS 99G1685** delivers uncompromising performance, ensuring that vacuum integrity is maintained with precision and confidence.

**Pros and Cons of Buying MKS 99G1685 Vacuum Isolation Valves**

The **MKS 99G1685** is a high-performance vacuum isolation valve commonly used in semiconductor manufacturing, research laboratories, and industrial vacuum applications. Below is a detailed analysis of its advantages and disadvantages.

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### **Pros**

1. **High Reliability and Durability**

The 99G1685 is designed for long-term use in demanding environments, such as semiconductor fabrication and thin-film deposition. Its robust construction, including stainless steel body and high-quality seals, ensures consistent performance over extended periods, reducing the need for frequent replacements.

2. **Precision Control and Leak Tightness**

This valve features a **pneumatic or manual actuation system** with precise control, allowing for accurate sealing and isolation of vacuum chambers. The **ultra-high vacuum (UHV) compatible design** ensures minimal leak rates, which is critical in applications where contamination must be avoided (e.g., semiconductor processing).

3. **Wide Compatibility with Vacuum Systems**

The valve is designed to integrate seamlessly with various vacuum systems, including **turbo pumps, diffusion pumps, and cryopumps**. It supports **CF (Conflat) flanges** (typically 1.5" or 2.75"), making it versatile for different setups.

4. **Fast Actuation and Response Time**

The pneumatic version of this valve operates quickly, allowing for rapid switching between open and closed positions. This is beneficial in automated processes where speed is essential.

5. **Low Outgassing Characteristics**

The materials used in its construction (such as stainless steel and specialized elastomers) minimize outgassing, which is crucial in applications requiring ultra-clean environments, such as **semiconductor wafer processing or particle physics experiments**.

6. **Modular and Customizable Options**

MKS offers various configurations, including **manual, pneumatic, and motorized versions**, as well as different flange sizes and connection types. This flexibility allows users to select the best option for their specific application.

7. **Proven Track Record in Critical Industries**

The valve is widely used in **semiconductor manufacturing, research laboratories, and aerospace applications**, where reliability is non-negotiable. Its reputation for performance in high-stakes environments adds credibility.

8. **Easy Maintenance and Serviceability**

The valve is designed for straightforward maintenance, with accessible seals and components that can be replaced without requiring specialized tools. This reduces downtime and operational costs.

9. **Compatibility with Control Systems**

The pneumatic version can be integrated with **proportional control systems**, allowing for fine-tuned operation in automated processes. This is particularly useful in **metalorganic chemical vapor deposition (MOCVD) and sputtering systems**.

10. **Long Warranty and Customer Support**

MKS Instruments, a well-established manufacturer, typically provides **extended warranties** and robust customer support, ensuring that users have access to technical assistance and spare parts when needed.

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### **Cons**

1. **High Initial Cost**

The 99G1685 is a **premium vacuum valve**, and its cost reflects its high performance and reliability. For small-scale or budget-conscious applications, this may be a significant investment compared to lower-end alternatives.

2. **Complex Installation and Calibration**

Due to its precision engineering, proper installation requires **expertise in vacuum systems**. Misalignment or improper sealing can lead to leaks or reduced performance. Some users may need to hire specialized technicians for setup.

3. **Dependence on External Power (Pneumatic Version)**

The pneumatic model requires a **compressed air supply**, which may not always be readily available in all laboratory or industrial setups. Users must ensure a stable air source or invest in additional equipment.

4. **Limited Lifespan Under Extreme Conditions**

While durable, prolonged exposure to **high temperatures, corrosive gases, or repeated thermal cycling** can degrade seals and internal components over time. Regular maintenance is necessary to extend its operational life.

5. **Potential for Seal Wear Over Time**

The elastomeric seals (e.g., Viton or Kalrez) can degrade due to **UV exposure, chemical exposure, or thermal stress**, leading to leaks. Replacement seals may be required periodically, adding to maintenance costs.

6. **Not Ideal for High-Flow Applications**

While excellent for isolation, the 99G1685 is not optimized for **high-throughput or high-flow vacuum systems**. For applications requiring rapid gas exchange, a different valve type (e.g., a fast-acting gate valve) may be more suitable.

7. **Training Required for Optimal Use**

Operators must be trained to use the valve correctly, especially in automated systems. Improper handling can lead to **damage, leaks, or inefficient operation**.

8. **Limited Availability of Spare Parts**

While MKS has a strong support network, some specialized components (e.g., custom seals or actuators) may have longer lead times, potentially causing delays in repairs.

9. **Noise in Pneumatic Operation**

The pneumatic version can generate **audible noise during actuation**, which may be a consideration in noise-sensitive environments (e.g., cleanrooms or research labs).

10. **Overkill for Simple Applications**

For **basic vacuum systems** (e.g., small-scale research or educational labs), the 99G1685 may offer **more features than necessary**, making it an unnecessary expense compared to simpler, lower-cost valves.

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### **Conclusion**

The **MKS 99G1685 vacuum isolation valve** is a **superior choice for high-precision, long-term vacuum applications**, particularly in **semiconductor manufacturing, research laboratories, and industrial processes where reliability and leak tightness are critical**. Its strengths lie in its **durability, precision, and compatibility with advanced vacuum systems**, making it ideal for mission-critical environments.

However, its **high cost, complex installation requirements, and need for proper maintenance** may make it less suitable for **budget-conscious or low-demand applications**. Users must weigh the **long-term benefits against the initial investment** and ensure their operational environment aligns with the valve s capabilities.

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### **Recommendation**

- You are working in **semiconductor fabrication, thin-film deposition, or ultra-high vacuum (UHV) research**.

- Your application requires **extreme reliability, minimal leak rates, and precise control**.

- You have the **budget and technical expertise** to install and maintain the valve properly.

- Long-term performance and **reduced downtime** are prioritized over initial cost.

- You are operating in a **low-budget or non-critical vacuum system** where a simpler valve (e.g., a basic gate valve) would suffice.

- Your application involves **high-flow or rapid gas exchange**, where a different valve type may be more efficient.

- You lack **expertise in vacuum system installation and maintenance**, as improper use could lead to failures.

For most **high-end vacuum applications**, the **MKS 99G1685 remains one of the best choices** due to its proven performance and industry-standard reliability. However, always **compare it with other models (e.g., MKS 99G1680, Leybold, or Edwards valves)** to ensure it meets your specific requirements before purchasing.

Details:

All equipment is sold as described. Shipping Carrier: We primarily use UPS Ground, FedEx, or USPS Priority Mail, depending on item size and destination. The sale of certain medical devices in the USA is regulated by Food and Drug Administration FDA state/local agencies.

part #: 99g1685 prices

• $109.00-$918.88

specifications valvplu:

• brand: Mks
• mpn: 99g1685
• part type: Vacuum Valve
• country of origin: United States

seller valvplu:

• rating: 99.3%
• city: Katy, Texas
• # reviews: 403

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• Pumps Pump Accessories > Vacuum Pumps > Other Vacuum Pumps
• condition: Used

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