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363-131 121-55A 14-.5
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Class Number: 138
Class Title: PIPES AND TUBULAR CONDUITS
Subclass Subclass
Number Title
26 WITH PRESSURE COMPENSATORS
27 .Freeze protecting
28 ..Expansible or compressible tube element
30 .Variable capacity chambers
31 ..Piston or plunger type
32 THAWING AND FREEZE PROTECTION
33 .Electric
34 .Anti-freeze substance
35 .Portable thawing apparatus
36 WITH WEAR INDICATOR
37 WITH FLOW REGULATORS AND/OR BAFFLES
38 .Heat transfer
39 .Flow facilitating
40 .Restrictors
41 ..With screen
42 ..Tortuous path
43 ...Variable restriction
44 ..Central path
45 ...Variable restriction
46 ..Variable restriction
89 WITH CLOSURES AND PLUGS
.Inflation stem type
89.1 ..Air and dust cap
89.2 ...Combined
89.3 ..Air cap
89.4 ..Dust cap
90 .Test plugs
91 .Double end
92 .Lateral opening
93 .Inflatable
94 .Laterally insertable
94.3 ..Line blinds
94.5 ...Pivoted
95 .Return bend type
96 R END PROTECTORS
96 T .Threaded
97 REPAIRING
98 .Patches
99 ..External
100 BREAKJOINT
101 .Distinct layers
102 .With base
103 COMBINED
104 .With indicating means
105 .With trench
106 .With external support structure
107 ..Suspended
108 .With means to support disparate element therein
109 .With end structure
110 .With hose protector
111 PLURAL DUCT
112 .With spacer and encircling elementt
113 .Surrounding radially spaced duct with axially spaced supports
for internal duct
114 .Coaxial
115 .Longitudinally extending common wall
116 ..Distinct
117 ..Complementary sections
118 FLEXIBLE
118.1 .Casing
119 .With means for facilitating collapse
120 .Joined sections
121 .Corrugated
122 ..Spirally
123 .Braided, interlaced, knitted or woven
124 ..Distinct layers
125 ...Plastic
126 ....Rubber
127 .....With metal
128 .Longitudinally seamed
129 .Spirally wound material
130 ..Oppositely wound
131 ..Metal core
132 ..Embedded
133 ...Metal
134 ..Metal
135 ...With interlocked or clamped edge
136 ....Packed or sealed
137 .Distinct layers
138 ..With intermediate metal element
139 ..Metal liner
140 DISTINCT LAYERS
141 .Bonded to each other
142 ..Brazed, soldered or welded
143 ..Metal
144 ..Spirally wound layer
145 .Coated
146 ..Diverse coating material
147 .With mechanical means to hold layers in contact
148 .Spaced
149 .With intermediate insulation layer
150 .With spiral seam
151 .With longitudinal seam
152 ..Material of one layer passing through seam
153 .Reinforced
154 SPIRALLY SEAMED
155 JOINED SECTIONS
156 LONGITUDINALLY SEAMED
157 .Sectional
158 ..With separate mechanical securing means
159 ...Bolt, nail, rivet or screw
160 ....Radially extending
161 ...Externally encircling
162 ..Tongue and slot
163 ..Bent over lip or flange
164 .With packing
165 .With wedge
166 .With tongue in slot
167 .With diverse locking means
168 .With interlocking hookss
169 .Diversity of seam
170 .Permanent type seam
171 ..Brazed, soldered or welded
172 REINFORCED
173 .Corrugated
174 .With embedded element
175 ..Clay, concrete or masonry
176 ...Reinforcement under tension
177 STRUCTURE
178 MISCELLANEOUS
* ******************************
* DIGESTS
* ******************************
DIG 1 Adhesive
DIG 2 Glass fiber
DIG 3 Teflon, Kel-F
DIG 4 Air conditioning
DIG 5 Pre-stress
DIG 6 Corrosion
DIG 7 Resins
DIG 8 Bent shaped retained
DIG 9 Cellular
DIG 10 Metal foil
DIG 11 Shape
* *Thermal and Electrical......*
* *Thermal and Electrical......*
* *thermal and electrical......*
* *thermal and electrical......*