About Vacuum Jacketed Piping
Vacuum Jacketed Piping Solutions
Vacuum Jacketed Pipe is essentially two pipes in one—an inner carrier pipe in which the cryogenic liquid is transferred, and an outer pipe that supports and seals the vacuum insulation, forming the “Vacuum Jacket” around the inner pipe. The inner line is suspended inside the outer jacket by a series of non-conductive supports. Depending on system design pressure, internal or external expansion joints are used to compensate for the thermal contraction of the inner line.
The integrity of our customers’ processes is what drives our quality program. The companies and research institutions we serve select us because of the exceptional results they can achieve using the highest quality VJP. The design and manufacture of Acme VJP are in accordance with the highest industry and manufacturing standards. Inner Carrier Line – The inner line is designed and built in accordance with ASME/ANSI B31.3. Typical Design Pressure = 150 psig. The inner carrier pipe and the outer jacket are constructed from stainless steel pipe or tubing. The inner line is wrapped with multi-layered super insulation which blocks radiative heat transfer. The entire annular space between the inner line and the outer jacket is evacuated to prevent convective heat transfer. The vacuum space is then factory sealed, forming a “static vacuum”. Chemical getters are used to maintain the vacuum space and provide maintenance-free operation for up to 20 years. The result is the most efficient transfer system available for cryogenic liquids. Outer Jacket – The outer jacket is designed to ASME Code Section VIII for unfired pressure vessels with an internal vacuum and external atmospheric pressure with the assembly at ambient temperature. Certified Welders – Qualified per ASME Section IX and ANSI B31.3 for MIG, TIG, and orbital welds. All inner process and outer jacket welds are helium mass spectrometer leak tested at 1 x 10-8 cc/sec. Vacuum pumpdown, bakeout and final retention testing is performed on every individual spool assembly.
Explore Vacuum Jacketed Pipe
The Acme Advantage for VJP
The Vacuum Jacketed Pipe division of Acme Cryogenics has recently completed a move into a new 38,400 square foot facility, located in Ball Ground, Georgia. This new facility will result in shorter lead times for customers and give Acme the ability to produce larger sizes of VJP (up to 12" NPS inner line size).
Each VJP project is managed by a “sales engineer” who has been trained in ASME B31.3 pipe design, cryogenic safety and VJP project management.
Our goal is to return your quote within 24 hours of submittal. Standard lead time for custom-designed VJP can be as little as four weeks from the approved design. Acme can offer an expedited build for critical delivery projects.
We offer surveying and on-site pipe design resulting in a safe and reliable system to fit your facility’s needs. This guarantees the VJP system fits your building, or we fix it – for free.
Custom-designed VJP systems, Quick-Fab VJ pipe and CryoFast piping covers virtually all uses of Vacuum Jacketed Pipe. In addition, Acme also offers a complete line of accessories including bayonet or field joint couplings, keep-colds, phase separators, tank switchers, and VJ SuperFlex hoses.
Acme Cryogenics has a nationwide field service team available to install your new VJP system. The field service team is also trained in repairing existing systems and preventative maintenance on your current vacuum lines, regardless of manufacturer.
Acme' standard manufacturer's warrenty is doubled when the VJ pipe is installed by Acme's field service technicians.
VALUE Vs. COST OF HEAT LEAK
MAKING THE RIGHT CONNECTIONS
MORE THAN THE SUM OF ITS PARTS
COMPLETE COMPONENT CHOICE
Acme offers two standard types of vacuum insulated connections depending on the design conditions and installation requirements. Bayonet Connections are designed for lower pressure applications up to 150 psig. Bayonet connections do not require any welding or vacuum work in the field. With proper planning and careful measurement, bayonets offer an easy-to-install, low profile, vacuum-insulated connection. Field Joint Connections offer improved thermal efficiency over bayonets but require a skilled field service team and specialized vacuum equipment for installation. Field joints are designed to handle large diameter pipes and higher pressure applications and offer increase structural durability due to the all-stainless steel welded construction. In addition, field joints allow for some adjustments during the installation.
In addition to VJP, Acme provides a complete component offering to complete our system design, manufacture, and installation capability.
Mechanical Keep-Cold Device – A float-activated device used to maintain liquid in the VJ Pipeline and vent the excess gas created by normal heat leaks.
Phase Separators – Typically used in applications where a single bulk tank is being used to provide both high pressures (90-150 PSIG) Nitrogen gas and low pressure (5-30 PSIG) liquid Nitrogen.
Scale-Based Tank Switcher – Used in applications that require multiple liquid cylinders to be used in succession without interruption by automatically switching to a new cylinder as each cylinder is emptied.
Vacuum Gauge Tube – Used to monitor vacuum levels in individual factory-sealed spool sections using a Hasting (DV-6R) Meter.
Pressure Relief Valve Assembly – Set to the design pressure as required in the system.
Vacuum Jacketed (VJ) Valves – Designed to have low heat leak and will not frost up during operation for in-line isolation or where superior thermal performance is required.
Internal Gas Traps – Used at the vertical drops/ use points and designed to keep liquid Nitrogen from "sitting" on un-insulated valves or components.
Vacuum Jacketed SuperFlex Hose – Remains warm and flexible during the transfer of cryogenic liquids. The vacuum insulation minimizes product loss and eliminates ice build-up. Note: MAWP =150 psig, not compatible with LOX Service.
CryoFast – Laboratory grade, high-efficiency VJP designed to quickly deliver LN2 for low flow applications with a limited LN2 source. Combine Acme's VJ SuperFlex Hoses to provide frost-free LN2 delivery from Dewar to your storage freezers.
Quik-Fab Modular VJP – When time is critical, Acme offers pre-engineered VJP with mechanical foam joints in a one to two-week lead time. Modular sections are offered in various length straights, with VJ elbow and tee sections, that can be assembled for a fast, low-cost, low heat leak VJP solution.
Acme Cryogenics Systems Design Checklist
tank location, equipment location, and piping elevation.
Provide an isometric sketch to clarify the piping configuration.
Acme Cryogenics will then provide isometric Autocad
drawings with dimensions for your verification. Acme
Cryogenics can provide any assistance needed in determining
layout or dimensions.
Size the pipe and components based on current flow rates, while
providing for any future expansion. Consult Acme Cryogenics
Identify liquid demands to help Acme Cryogenics determine the
components needed to maximize your piping system's
Highlight any installation points of interest, such as wall
penetrations, close quarters, existing fixtures, drop ceilings, etc.
Determine any installation restrictions for length with regards
to access pipe and assembly.
Liquid Nitrogen Distribution System
Vacuum Jacketed Liquid Nitrogen Piping
♦ The liquid nitrogen storage tank and the Vacuum Jacketed Piping are part of the liquid nitrogen supply system that is designed to store and provide low-pressure liquid nitrogen to cryogenic equipment. The piping system is designed to be modular in construction so that it can easily be expanded inside a facility.
♦ The equipment that is provided is manufactured for use with extremely low temperatures -320°F (-196° C). Any material coming in contact with liquid nitrogen must be either stainless steel, brass, bronze, copper, aluminum, Teflon™, or Kel-F. Any material coming in contact only with cold vapors must be appropriate for extremely low temperatures.
Related Codes and Standards
♦ The equipment that is provided under this specification should be manufactured to the appropriate codes and specification, including but not limited to the following:
1. Bulk Storage Tanks
ASME Section 8, Division I-unfired pressure vessel. The liquid storage vessel must comply with the latest addendum.
2. Vacuum Jacketed Pipe
- ANSI Section B31.3 Process Piping.
Typical for Basic Systems
Attributes For Your Vacuum Jacketed System
♦ Field welded couplings for lower heat inleak and material costs
♦ 1" to 2" headers for main or high usage branch runs
♦ 1/2" drops to equipment
♦ Vacuum jacketed in-line valves for branch isolation during shutdown or repair
♦ DV-6R for monitoring vacuum level of VJ Pipe
♦ Internal gas traps prevent frosting of standing end connections when not in use
♦ System relief valve for line safety (if located indoors, it must be piped to exterior)
♦ Acme Cryogenics Electronic or Mechanical Keep-Colds maintain cold temperatures at the main header and use points
♦ Capped bayonet or field joint coupling for future expansion
♦ Extended stem cryogenic control valves (usually end use conditions)
♦ Vacuum Jacketed Flexible Pipe for use with vibrating equipment or minimizing alignment problems
Please contact us or request a quote for systems that are not standard.
Vacuum Jacketed Piping (VJP) System
Individual Connection Components & Additional Equipment
A bayonet is a mechanical connection between two sections of Vacuum Jacketed Pipe that eliminates the need for any welded connections. The bayonet is a low heat inleak device with telescoping male and female components. Due to a close tolerance design, Acme Cryogenics' "low profile" bayonets
utilize a metal-to-metal in-line seal with a silicon O-ring placed between the flanges. These combine to make a reliable heavy-duty cryogenic seal between the two VJP sections and simultaneously preserve the low heat inleak of the system.
Field Joint Couplings
Field joint couplings are vacuum-insulated field welded connections between two sections of Vacuum Jacketed Pipe. They have a long heat leak transition between the outer jacket and the inner pipeline to reduce the heat input into the system. After the weld is made, the joint is insulated and coupling is moved into place over the section. The coupling is then field welded to the collars on the ends of the two piping spools. This coupling is
then evacuated to a low vacuum to insure a low heat leak. This type of system is usually installed by Acme Cryogenics' field crew.
Acme Cryogenics Electronic Keep-Cold
The Electronic Keep-Cold uses a sensor activated vent valve to maintain liquid in the VJ line and vent the excess gas created by normal heat leak. The Electronic Keep-Cold helps provide liquid on demand to your application.
Acme Cryogenics Mechanical Keep-Cold
The Mechanical Keep-Cold is a float activated device used to maintain liquid in the VJ line and vent the excess gas created by normal heat leak. The Mechanical Keep-Cold helps provide liquid on demand to your application.
Relief Valves are required to protect the line in the event an isolation valve is shut with liquid in the line. All reliefs should be less than or equal to 150 psi or 10.34 Bar (unless otherwise specified).
Vacuum Jacketed Flex
For ease of installation or to accommodate the equipment involved, Vacuum Jacketed Flexible Pipe is available upon request.
Vacuum Jacketed Valves
Vacuum Jacketed Valves are used as in-line control valves. They allow the luxury of maintaining the high insulation valve and preventing frost up.