Sealing a 6 torr closed system vacuum

In summary, the conversation discusses the design of a two chamber stainless steel vacuum system with a flexible tube and valve that can maintain a vacuum of 6 torr for at least a year. The chambers have specific dimensions and will be connected with stainless steel tubing and KF-25 connectors with Viton gaskets. The question is raised about using an air conditioning service pump to achieve the desired vacuum, or alternatively heating the vacuum chamber containing water to create a powerful vacuum. The issue of sealing the system with a gate valve and threaded holes is also discussed, with a recommendation to check the leak rating with the manufacturer and consider using vacuum welding to eliminate virtual leaks. A recommended ISO butterfly valve for vacuum systems is also suggested, with a low leak rate
  • #1
thefixerupper
1
0
I wish to design a two chamber stainless steel vacuum system where the two vacuum chambers are connected via a flexible tube with a valve. The system needs to be able to be pumped down to 6 torr and must be able to maintain that vacuum for at least a year without pumping. The size of the chambers are 2" x 4" x X 12" X 0.12" (Height, Width, Length, Wall Thickness) and 6" x 0.065" (Diameter, wall thickness). They will be connected with stainless steel tubing and KF-25 connectors with Viton gaskets.

Question:
I have an air conditioning service pump-- will that be able to bring the vacuum to 6 torr? Otherwise, would it be possible to create at least a 6 torr vacuum by heating (to the point of boiling) the vacuum chamber that contains water and then sealing the system? The condensing water vapor should create a powerful vacuum, correct?

If an vacuum pump must be used, what is a good way to seal off the system? I have a gate valve (with elastomer seals), but it has a couple of 1/4" threaded holes in it (currently fitted with teflon and stop plugs). My concern is that system will leak through the threaded holes. Is there a recommended way to seal threads to retain vacuum?
 
Physics news on Phys.org
  • #2
You can check the leak rating for your valve with the manufacturer.

For example here is an ISO butterfly valve designed for vacuum systems:
http://www.pchemlabs.com/product.asp?pid=3572

"Butterfly Valves have the advantages of having a small footprint, being turned completely off to on in one 90 degree rotation of the handle, while offering a high gas throughput and conductance. These vacuum butterfly valves are designed to have a low leak rate, typically on the order of 1x10-9 std. cc/sec. Helium. These butterfly valves have a NW-25 vacuum flange for connection to the vacuum system, are manually operated, and made of stainless steal." Price: $345.

Your vacuum chamber will also "leak" from the interior walls (out-gassing), and from any "virtual leaks" in the welding ... "vacuum welding" is a technique which eliminates these virtual leaks:
http://www.vacuumlab.com/Articles/Understanding Virtual Leaks.pdf
 

1. What is a closed system vacuum?

A closed system vacuum is a vacuum environment that is completely sealed off from the outside atmosphere. This means that there is no exchange of matter or energy between the system and the surroundings.

2. How is a 6 torr closed system vacuum achieved?

A 6 torr closed system vacuum is achieved by removing all air and gases present in the system through a process called evacuation. This is typically done using a vacuum pump, which creates a low-pressure environment by removing air molecules from the system.

3. Why is it important to achieve a 6 torr closed system vacuum?

A 6 torr closed system vacuum is important because it allows for a controlled environment for experiments or processes that require a low-pressure or oxygen-free environment. It also helps prevent contamination from outside sources, which can affect the accuracy and reliability of experimental results.

4. How can the vacuum level be measured in a closed system vacuum?

The vacuum level in a closed system vacuum can be measured using a vacuum gauge, which measures the pressure inside the system in units of torr or other pressure units. Other methods of measuring vacuum level include using a manometer or a pressure transducer.

5. What are some common applications of a 6 torr closed system vacuum?

A 6 torr closed system vacuum has a wide range of applications in scientific research, industrial processes, and medical procedures. It is commonly used in material science experiments, semiconductor manufacturing, and freeze-drying processes. It is also used in vacuum packaging of food and pharmaceuticals, as well as in medical procedures such as electron microscopy and radiotherapy.

Similar threads

Sealing a low-vacuum closed system
    • Other Physics Topics
Replies
9
Views
10K
I Building a Vacuum Filling System: Valves & Fine Leaks
    • Other Physics Topics
Replies
5
Views
2K
Vacuum Pump Solution for Perfectly Sealed Chamber
    • Other Physics Topics
Replies
7
Views
3K
I Graduation of air flow inside a vacuum chamber
    • Classical Physics
Replies
4
Views
1K
Help me design a Vacuum Drying system
    • DIY Projects
Replies
7
Views
2K
Need advice on pinch-off tool for cold cold-weld sealing
    • General Engineering
Replies
1
Views
3K
A single atom in a cold, closed, vacuum system.
    • Other Physics Topics
Replies
11
Views
3K
Calculating thickness/exoskeleton vacuum chamber
    • Other Physics Topics
Replies
4
Views
9K
Choosing a heater band for vacuum system bakeout
    • General Engineering
Replies
2
Views
1K
  • Poll
Vacuum pump and creation of vacuum
    • Other Physics Topics
Replies
31
Views
17K

Hot Threads

Recent Insights

Back
Top