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NEMA HAS NOW INSTITUTED A RECOMENDATION
FOR APPLICATION OF CEMENT FOR PVC CONDUIT.
NEMA HAS ADOPTED ASTM
D-2564 WHICH SETS THE STANDARD FOR THE
VISCOCITY LEVELS REQUIRED FOR THE CEMENTING OF PVC CONDUIT. THIS
STANDARD OUTLINES THE REQUIREMENTS FOR DETERMINING CONDUIT
SCHEDULES, AND PIPE SIZE.
LOOK FOR THE NSF
LOGO: NSF CERTIFIES
COMPLIANCE WITH ASTM-D2564. THE NSF LOGO
ON THE CAN IS THE ONLY ASSURANCE THE PRODUCT COMPLIES WITH THE
ASTM STANDARD.
MANY MANUFACTURERS DON'T ADHERE TO THIS
STANDARD. SOME LABEL THE CAN STATING COMPLIANCE WITH ASTM
D-2564, HOWEVER THEY DON'T SPECIFY THE SIZE LIMITATIONS FOR THEIR
CEMENT. WITHOUT THE CONDUIT SIZE LISTING, PRINTING THE ASTM
COMPLIANCE TELLS YOU NOTHING IN RELATION TO THE NEMA
RECOMENDATION.
UNITED ELCHEM LABELS THEIR CAN TO ASSIST YOU IN
DETERMINING THE CORRECT BODIED CEMENT FOR WHATEVER APPLICATION YOU
NEED.
303 SERIES REGULAR BODIED CEMENTS- GOOD THRU 4"
SCHEDULE 40.
403/404 SERIES MEDIUM BODIED CEMENTS- GOOD THRU
6" SCHEDULE 80.
2000 SERIES PLUMBTITE- GOOD THRU 6" SCHEDULE
80.
2600 SERIES POLARWELD- GOOD THRU 6" SCHEDULE 80.
ALSO GOOD DOWN TO 0 DEGREES.
THE FOLLOWING STATEMENTS WERE TAKEN FROM THE NEMA
WEBSITE:
Solvent-Cementing
Joints for PVC Rigid
Nonmetallic Conduit,
Duct, and Fittings
Most forms of PVC conduit, duct, and fittings are
meant to be assembled or joined by means of solvent-cementing of the
integral bells or PVC couplings.
Solvent cements contain chemicals which dissolve
the surface of the PVC, softening it. As the chemicals evaporate,
they leave a PVC resin behind which fuses the mating
surfaces.
To Prime or Not to Prime?
The National Electrical Code (NE C®)
does not require primer to be used in the
joining of PVC conduit. However, under some
conditions, primer can aid in the ease of assembly and enhance the
quality of the joints. Primers are a form of chemical cleaner that
may be used to remove surface impurities, soften, and dissolve the
joining surfaces in order to better prepare them for
solvent-cementing.
Selection of Solvent Cement
Solvent cements intended for use with PVC conduit and duct should
meet all the applicable requirements of ASTM D 2564, "Solvent
Cements for Poly(Vinyl Chloride) (PVC) Plastic Piping Systems."
Since they are available in a wide range of viscosity and wet film
thicknesses, the nature of the particular project must be considered
when trying to decide between a regular, medium, or heavy-bodied
cement. | 
