SCOPE:
This specification outlines minimum manufacturing requirements for
Polyvinyl Chloride (PVC) iron pipe size (IPS) seamless, extruded
round duct. This duct is intended for use in industrial fume handling
systems where temperatures encountered do not exceed 140°F.
PVC MATERIALS:
The material used in the manufacture of the duct shall be a virgin,
rigid polyvinyl chloride (PVC) compound, with a Cell Classification
of 12454 as defined in ASTM D1784. This compound shall be dark gray
in color or as specified, and shall be domestically produced PVC
material designated as Harvel H707 compound, PVC 1120.
DIMENSIONS:
All PVC extruded duct shall be manufactured in strict accordance
to the requirements established by Harvel Plastics, Inc. for the
production of extruded duct piping; including the physical dimensions
and tolerances as stated on Page 2 of this specification.
MARKING:
Product marking shall include the manufacturer’s name (or
the manufacturer’s trademark when privately labeled); the
nominal duct size; material designation; and the date of manufacture.
| SAMPLE SPECIFICATION:
All exhaust duct piping, sizes 6” through 24”,
shall be PVC seamless extruded type, as manufactured by Harvel®
Plastics Inc. This duct pipe shall be extruded from a Type
I, Grade I Polyvinyl Chloride (PVC) compound with a Cell Classification
of 12454 per ASTM D1784, trade name H707 PVC. All extruded
PVC duct shall have a maximum flame spread rating of 25 or
less per ULC S102.2. All PVC extruded duct pipe shall meet
Harvel Plastics Inc. published standards with regard to material
and dimensions, and shall carry a maximum temperature rating
of 140°F. All extruded duct pipe shall be manufactured
in the USA, using domestic materials, by an ISO 9001 certified
manufacturer, and shall be stored indoors at the manufacturing
site until shipped from the factory. All extruded PVC duct
pipe shall be marked with the manufacturer’s name or
identifying symbol. |
DIMENSIONAL SPECIFICATIONS
| SIZE |
AVG. OD |
AVG. OD TOL. |
O of R TOL. |
MIN. WALL |
AVG. WALL |
MAX. WALL |
WT(lbs) PER FT. |
6"x1/8 |
6.625 |
+/- .020 |
+/- .050 |
.105 |
.122 |
.140 |
1.530 |
6" |
6.625 |
+/- .020 |
+/- .050 |
.172 |
.187 |
.202 |
2.275 |
7" |
7.375 |
+/- .020 |
+/- .050 |
.172 |
.187 |
.202 |
2.534 |
8" |
8.625 |
+/- .020 |
+/- .075 |
.172 |
.187 |
.202 |
2.982 |
9" |
9.375 |
+/- .025 |
+/- .075 |
.172 |
.187 |
.202 |
3.239 |
10" |
10.750 |
+/- .025 |
+/- .075 |
.172 |
.187 |
.202 |
3.733 |
11" |
11.375 |
+/- .025 |
+/- .075 |
.172 |
.187 |
.202 |
3.944 |
12" |
12.750 |
+/- .025 |
+/- .075 |
.172 |
.187 |
.202 |
4.440 |
14" |
14.000 |
+/- .030 |
+/- .075 |
.172 |
.187 |
.202 |
4.884 |
16" |
16.000 |
+/- .030 |
+/- .075 |
.172 |
.187 |
.202 |
5.586 |
18" |
18.000 |
+/- .040 |
+/- .080 |
.172 |
.187 |
.202 |
6.750 |
20" |
20.000 |
+/- .070 |
+/- .140 |
.199 |
.219 |
.239 |
8.144 |
24" |
24.000 |
+/- .090 |
+/- .180 |
.230 |
.250 |
.270 |
11.163 |
O of R = Out of Roundness Factor at time of extrusion *I.D. Sizes
TABLE l
| GENERAL |
value |
test method |
Cell Classification |
12454 |
ASTM D1784 |
Specific Gravity |
1.40±.02 |
ASTM D792 |
| MECHANICAL |
Tensile Strength, psi @ 73°F |
7,450 |
ASTM D638 |
Modulus of Elasticity, psi @ 73°F |
420,000 |
ASTM D638 |
Izod Impact, ft-lb/in @ 73°F |
0.75 |
ASTM D256 |
| THERMAL |
Coefficient of Linear Expansion (in/in/°F) |
2.9 x 10-5 |
ASTM D696 |
| FLAMMABILITY |
Flammability Rating |
V-0 |
UL 94 |
Flame Spread |
0-25
|
ULC |
| HARDNESS |
Shore D |
82±3 |
ASTM D2240 |
GENERAL RECOMMENDATIONS
The information provided herein is intended as a general guide based
on common practice. This information may be considered as a basis
for recommendation only, and not as a guarantee for its accuracy,
suitability for particular applications, or the results to be obtained
therefrom. Individual differences are a matter of design preference
and shop practice.
Joining
Thermal welding shall be performed by personnel adequately trained
in the art of PVC welding utilizing the hot gas fusion welding method
using virgin PVC filler welding rod as manufactured for this purpose.
When solvent cemented connections are utilized, the use of an extra
heavy bodied PVC solvent cement and appropriate primer is recommended
due to tolerance extremes that can be encountered when working with
duct and fabricated duct fittings. Proper solvent cement joining
procedures shall be followed.
Hangers and Supports
Hangers selected shall have an adequate load-bearing surface free
of rough or sharp edges and shall not cause damage to the duct during
use. Hangers and hanger hardware shall be of a corrosive-resistant
material suitable for use in the system environment.
Ductwork is to be supported independently of hoods, scrubbers,
fans, tanks or other equipment wherever possible. Where flexible
connections are provided as expansion joints, a suitable hanger
or support shall be provided at each end of the flexible connection.
Consideration shall be given to the possibility of solids accumulation;
adequate system support shall be provided where required.
Drains shall be installed where accumulation of moisture is expected
at low points in the system as indicated on the drawings.
Handling and Storage
Care shall be used when transporting and storing duct to prevent
physical distortion. Duct shall not be stored close to heat producing
sources, subjected to external loads, or over stacked when stored.
Damaged sections must be cut out and discarded.
System Components
All duct fittings, fume hoods, fans, blast gates and other system
components shall be fabricated from PVC sheet or PVC duct material
of the same wall thickness. The use of Type I Grade I (Cell Classification
12454 per ASTM D1784) PVC material is recommended to maintain system
compatibility.
Reference Harvel® Plastics, Inc. Duct Bulletin HPB-109 and
Product Bulletin 112/401 for information pertaining to chemical
resistance, joining methods, hangers and supports, collapse pressure
ratings, system components, and other installation related data.
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