 |
Wheatland TUBE COMPANY DIVISION OF JOHN MANEELY COMPANY |
Rigid Steel Conduit Specifications
Wheatland Hot-dipped Galvanized Rigid Steel Conduit is
manufactured in conformance to standards established by the American National Standards
Institute, the Underwriters
Laboratories and the Federal Specification. In preparing bids, it may be stated that
Wheatland Rigid Conduit conforms to:
- American National Standard Institute C80.1-
- Federal Specification WW-C-581
- Underwriters Laboratories Specification No. 6
- National Electrical Code-Article 346
UNDERWRITERS LABORATORIES SPECIFICATION NO. 6
The specifications for rigid steel conduit established by the
Underwriters Laboratories cover both the manufacture and testing of the conduit in detail.
The sections referring to the qualifications of the conduit are condensed and summarized
below. Be assured that Wheatland Hot-dipped Galvanized Rigid Steel Conduit meets or
exceeds the UL specifications.
The Tube
Each tube used in the manufacture of rigid metal conduit shall be
steel (or other suitable metal) and shall have a circular cross-section sufficiently
accurate to permit the cutting of clean, true threads. The wall thickness shall be uniform
through the length of the tube. The welding of all seams shall be thoroughly well done.
The welded seam shall be free from metal trimmings, sharp edges and
sharp projections.
Both the inside and outside surfaces of the tube shall be thoroughly
cleaned so that the protective coating will have a smooth finish. Before the protective
coating is applied, the interior surface of the tube shall be examined to be sure it is
free from scale.
Each tube used for rigid metal conduit shall be capable of being
bent cold into a quarter circle around a mandrel, the radius of which is four times the
trade size of the tube, without developing cracks or opening a weld.
The Protective Coating
Both the inside and outside of ferrous metal rigid conduit shall be
protected against corrosion by a coating of zinc (or enamel or equivalent
corrosion-resistant coating). The coating shall be sufficiently elastic to prevent its
cracking or flaking off when a finished sample of 1/2-inch conduit is tested up to a year
after manufacture by bending it into a semi-circle, the inner edge of which has a radius
of
3 1/2 inches.
A protective coating of zinc shall be such that a sample of finished
rigid ferrous-metal conduit will not show a fixed deposit of copper after four one-minute
immersions in a standard copper sulfate solution.
The Threads
Each length of conduit is to be threaded on both ends and chamfered
to remove burrs and sharp edges on the interior surface. All threads are to be clean and
full cut. If threads are cut after the protective coatings are applied, they shall be
treated to prevent corrosion before the conduit is installed.
The Finished Conduit
Every piece of conduit is to be inspected prior to shipment to be
sure it is free from poor coating, scale, burrs or fins, embossing on interior surfaces or
other defects.
Each length of conduit shall be marked "rigid metal
conduit" and indicate the type of material. In addition, it shall be marked with
manufacturer's name or trade mark.
FEDERAL SPECIFICATION WW-C-581
This specification covers zinc-coated rigid steel conduit in all
common trade sizes. Its general requirements are that products furnished under this
specification conform as applicable to ANSI C80.1 and UL 6 for rigid steel conduit.
Other provisions of WW-C-581 which should be noted when preparing
bids are summarized here. For details on packaging and quality assurance, refer to the
full specification.
Standard Commercial Product
The conduit shall, as a minimum, be the manufacturer's standard
commercial product with any added features needed to comply with the requirements.
Identical Items
Conduit, couplings, elbows and nipples of the same classification
furnished under any specific contract shall be physically and mechanically identical. No
deviation will be acceptable without prior written approval of the contracting officer.
Material
All material shall be new and unused. Material not specified shall
be of the same quality used for the intended purpose in commercial practice. Materials
used shall be free from defects which would adversely affect the performance or
maintainability of individual component or the overall assembly.
|
