|
|
|
Examples: Jacketed Pipe
| Standard
Jacketed Pipe. This type of jacketed pipe, compared to the
other types, provides the most uniform temperature maintenance because it effectively
heats all of the core piping as well as connecting flanges. If the heating medium shuts
off and the process freezes in the line, Standard Jacketed Pipe offers the best chance for
quick melt out. Unfortunately, not all processes yield to melt-out cycles. Sulfur Recovery
Units (SRU's) sometimes have process upsets that cause catalyst carryover to the sulfur
stream. These rock-hard agglomerates build up in the core piping and must be cleaned out
by hard labor. The 6" x 8" piping shown right is typical SRU-to-pit sulfur
piping. Each change of direction was designed with a jacketed cross instead of a
conventional jacketed elbow. The cross allows clean-out access to the core pipe regardless
of flow direction. |
 Standard Jacketed Pipe
|
|
|
|
| Swaged Jacketed
Pipe. Compared to Standard Jacketed Pipe, this type of pipe
offers significant cost savings because equipment with line (core) size flanges can be
used. The piping spools shown right were designed for a viscous bottoms distribution
system in continuous service using liquid hot oil as the heating medium. All hot oil
connections are ANSI Class 300, 1-inch flanges. Core piping is stainless steel. Jacket
piping is carbon steel. In batch-type (cyclical) processing, this material combination
probably would create unacceptable stress levels. |
Swaged Jacketed Pipe
|
|
|
| Insert
Flanged Jacketed Pipe. The jacketed pipe spool
shown right incorporates three sizes of jacketed pipe: 6" x 8", 8" x
10" and 10" x 12". The spool is fitted with both Reducing and Non-Reducing
Insert Flanges. At equipment connections Non-Reducing Flanges are used to take advantage
the cost savings afforded by nominal-size connections. Pipe-to-pipe connections use
Reducing Flanges which are a little easier to bolt up than Non- Reducing Flanges. |
Insert Flanged Jacketed Pipe
|
|
|
| High-Pressure
Jacketed Pipe. Hub-type connectors are frequently used in
high-pressure jacketed piping systems because the hubs save both weight and space compared
to the weight and space of ANSI Class 1500 or 2500 flanges. The jacketed 4" x 6"
spool shown right uses a standard jacketed hub with external jumpovers to transfer heating
medium. The core is designed for a pressure of 1500 psi. Flow-through hubs are available
that allows the heating media to transfer from one hub to another, eliminating external
jumpover connections. |
 Hub-Type Jacketed Pipe
|
|
| Hybrid Jacketed
Pipe. Aggressive processes that attack concealed weld zones
in core piping have long been a trouble spot for designers of jacketed pipe. If a
concealed weld fails, cross contamination occurs. Either the process enters the heating
medium or the heating medium enters the process. Cross contamination is very difficult to
trace and expensive to correct. Hybrid Jacketed Pipe minimizes the possibility of cross
contamination. The concept is simple: No concealed welds. Swaged Jacketed Pipe is used for
all straight piping sections with the jackets terminating before a core weld. Fittings are
welded into the core pipe un-jacketed. Then bolt-on heating jackets are used to heat the
fittings. Cross contamination resulting from weld failure is virtually impossible. The
spool piece, right, is typical of Hybrid Jacketed Pipe. Bolt-on jackets heat two elbows
and a tee. Swaged jacketing is used on five straight sections. All core welds are
accessible by removing the bolt-on jackets. |
 Hybrid Jacketed Pipe
|
|
|
|
