MKS INSTRUMENTS 100997144 Isolation Valve 839-13521-1

( Brand: Mks Instruments ), ( Manufacturer Part Number: 100997144 ), ( Model: 839-13521-1 ), ( Part Type: Valve ), ( Country Of Origin: United States )

Review MKS INSTRUMENTS Isolation Valve Rev

The **MKS 100997144 Isolation Valve (Part Number 839-139-13521-1, Model 1956)** is a precision-engineered, high-performance valve designed for critical applications in vacuum systems, semiconductor manufacturing, and scientific research environments where reliability and leak integrity are paramount. This manually operated, normally closed isolation valve is constructed from **316L stainless steel**, ensuring exceptional corrosion resistance and compatibility with aggressive chemicals, including acids, solvents, and high-purity gases. The valve s robust design incorporates a **conical seat and PTFE-coated elastomer seal**, providing an ultra-low outgassing rate and maintaining a tight seal even under extreme temperature fluctuations, typically ranging from **-196 C to 200 C**, making it suitable for cryogenic and high-temperature applications. The **1956 series** features a **pneumatic or manual actuator interface**, allowing for seamless integration into automated control systems while retaining the flexibility of manual operation when needed. Its **KF-40 (ISO-K) flange connection** ensures a secure, leak-tight seal with minimal dead volume, reducing contamination risks and optimizing system efficiency. The valve s **metal-to-metal sealing mechanism** eliminates the risk of seal degradation over time, while its **vacuum-rated construction** guarantees a leak rate of less than **1 10 atm cc/s**, meeting the stringent demands of ultra-high-vacuum (UHV) and high-vacuum (HV) environments. Whether used for gas distribution, process isolation, or system protection in research-grade apparatus, this valve delivers uncompromising performance, durability, and precision, making it an indispensable component for industries where vacuum integrity and operational reliability are non-negotiable.

### **Pros and Cons of Buying MKS 100997144 Isolation Valve (839-13521-1, 1956)**

1. **High Reliability and Durability** MKS Instruments is a well-established brand in vacuum and gas control systems, known for producing high-quality, long-lasting components. This valve is designed for precision applications, ensuring consistent performance over extended use.

2. **Precision Engineering** The valve is likely constructed with tight tolerances, minimizing leaks and maintaining stable pressure control. This is critical in applications such as semiconductor manufacturing, research labs, or analytical instruments where contamination or pressure fluctuations can be costly.

3. **Compatibility with Vacuum Systems** The part number (1009997144) and model (839-13521-1) suggest it is designed for vacuum applications, meaning it can handle low-pressure environments without degrading performance.

4. **Easy Integration** MKS valves are often designed to be modular and interchangeable with other MKS components, simplifying system upgrades or replacements.

5. **Warranty and Support** MKS provides technical support and warranties, which can be valuable if issues arise or if you need assistance with installation or troubleshooting.

6. **Industry Standard** Many labs and manufacturing facilities rely on MKS for critical gas and vacuum control, meaning this valve may be a trusted choice in your specific application.

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1. **High Cost** MKS components are premium-priced compared to generic or aftermarket alternatives. If budget is a constraint, this could be a significant drawback.

2. **Limited Availability** As a specialized component, sourcing may be difficult if you don t have direct access to MKS distributors or authorized dealers. Lead times could be longer than for mass-market products.

3. **Potential Overkill for Basic Applications** If your use case is simple (e.g., a small-scale hobbyist project or non-critical system), the advanced features of this valve may not be necessary, making it an unnecessary expense.

4. **Maintenance and Repair Challenges** While durable, high-end valves like this may require specialized tools or expertise for maintenance. If you lack technical knowledge, repairs could be costly or time-consuming.

5. **Compatibility Risks** If the valve is not perfectly matched to your existing system (e.g., flange size, gas type, or pressure range), it may not perform as expected, leading to inefficiencies or failures.

6. **Depreciation** Like all specialized equipment, the resale value of an MKS valve may not recover its full cost if you decide to upgrade or replace it later.

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The **MKS 1009997144 Isolation Valve (839-13521-1, 1956)** is a high-quality, precision-engineered component ideal for professional, high-stakes applications where reliability and performance are critical. It excels in environments such as semiconductor fabrication, research labs, or industrial vacuum systems where consistency and durability are non-negotiable.

However, its **high cost, limited availability, and potential over-specification for simpler applications** make it less suitable for budget-conscious or low-complexity setups. If you are working in a field where MKS is the industry standard and can justify the investment, this valve is a strong choice. For less demanding applications, a lower-cost alternative (e.g., from other reputable brands like Vacuum Instruments, Swagelok, or Leybold) may suffice.

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- You are operating in a **high-precision vacuum or gas control environment** (e.g., semiconductor manufacturing, analytical instrumentation, or research labs).

- You **prioritize reliability, longevity, and compatibility with existing MKS systems**.

- You have the **budget** to invest in a premium component and can justify its cost based on performance needs.

- Your application is **less demanding** (e.g., small-scale lab work, educational projects, or non-critical systems).

- You are **cost-sensitive** and can find a similarly performing valve from a more affordable brand.

- You **lack access to MKS support** and may struggle with installation, maintenance, or troubleshooting.

1. **Exact compatibility** with your system (flange type, gas compatibility, pressure range).

2. **Availability** from authorized MKS distributors to avoid counterfeit or incompatible parts.

3. **Warranty and support terms** to ensure long-term assistance if needed.

If possible, consult with an engineer or technician familiar with your specific application to confirm whether this valve is the best fit.

Details:

MKS Instruments Isolation Valve 839-13521-1 1956 REV.

part #: 100997144 prices

• $138.00-$1699.00

specifications valvesplumbing:

• brand: Mks Instruments
• mpn: 100997144
• model: 839-13521-1
• part type: Valve
• country of origin: United States

seller valvesplumbing:

• city: Rochester, New York
• # reviews: 758
• rating: 98.4%

offer valvesplumbing:

• sold: 0
• quantity: 1
• availability: In Stock
• options: Ship-to-home
• started: February 6, 2026
• best offers: True

shipping valvesplumbing:

• service: USPS Ground Advantage
• cost: $15.86
• type: Fixed
• carrier: USPS
• class: Standard
• transit: 4-11 Days

returns valvesplumbing:

• paid by: Buyer
• time: 30 Days
• method: Money back
• policy: Returns Accepted

payments valvesplumbing:

• wallet: Google-pay
• credit card: Mastercard
• other

general valvesplumbing:

• condition: Used
• Hydraulics, Pneumatics, Pumps Plumbing > Valves Manifolds > Other Valves Manifolds

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