HARRISON

Machine & Plastic Corporation

HARRISON
SUPERDUCT®
  PVC Duct Pipe

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The pressure ratings given are for water, non-shock, @ 73°F. The following temperature de-rating factors are to be applied to the working pressure ratings (WP) listed when operating at elevated temperatures.

OPERATING TEMPERATURE (°F)	DE-RATING FACTOR
73	1.00
80	0.88
90	0.75
100	0.62
110	0.51
120	0.40
130	0.31
140	0.22

Multiply the working pressure rating of the selected pipe at 73°F, by the appropriate de-rating factor to determine the maximum working pressure rating of the pipe at the elevated temperature chosen.

EXAMPLE: 10" PVC SCHEDULE 80 @ 120°F = ?
230 psi x 0.40 = 92 psi max. @ 120°F

THE MAXIMUM SERIVCE TEMPERATURE FOR PVC IS 140°F.

Solvent cemented joints should be utilized when working at or near maximum temperatures.

Threading of Schedule 40 PVC pipe is not a recommended practice due to insufficient wall thickness. Thread only Schedule 80 or heavier walls. Threading requires a 50% reduction in pressure rating stated for plain end pipe @ 73°F.

Chemical resistance data should be referenced for proper material selection and possible de-rating when working with fluids other than water.

ASTM STANDARD D1784 MATERIAL EQUIVALENTS: Cell Classification 12454 = PVC Type 1 Grade 1 = PVC 1120

Pipe sizes shown are manufactured in strict compliance with ASTM D1785

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General Specifications for Standard Schedule 40 and Schedule 80 PVC Fabricated Drainage Fittings

Scope

This specification is applicable to fabricated fittings, as furnished by Harrison Machine & Plastic Corporation, as they pertain to (PVC) Polyvinyl Chloride Schedule 40 & Schedule 80 fitting configurations.

Materials of Construction

(PVC) Polyvinyl Chloride

Fittings are to be manufactured from PVC material which meets or exceeds the requirements of ASTM D-1784, cell classification 12454B, Type 1, Grade 1.

Pressure pipe used in fabrication must conform to ASTM D-1785 (Schedule 40 & Schedule 80) or ASTM D-2241 (SDR-26 & SDR-41) and listed by the National Sanitation Foundation (NSF) for potable water applications.

Sheet stock material (where used) must conform to ASTM D-1784, cell classification 12454B, Type 1, Grade 1, normal impact, and manufactured without the use of plasticizers or fillers.

Solvent Cement and Welding Rod (PVC)

All solvent cements used, to conform to ASTM D-2564, listed by NSF for potable use applications

Welding rod used in the manufacture of the above fittings, shall conform to ASTM D-1784, cell class 12454B for PVC

Assembly and Construction Procedures

Fittings shall be Butt Fusion (machine) welded where feasible or hand welded (fillet welded) by qualified and experienced craftsman trained in the art of thermoplastic welding and fabrication.

PVC Schedule 40 fittings will be white or gray in color (this color code applies to both pressure and drainage patterns)

Fitting diameters, 18", 20", & 24", as a customer option, may also be constructed from SDR-26 or SDR-41 pipe dependent upon the pressure rating required (i.e. 160 psi or 100 psi).

Dimensional Specifications

All cataloged fitings to be constructed in accordance with Harrison Machine and Plastic Corporation, published drawings. Non-cataloged fittings will be furnished in accordance to or as agreed upon customer specifications.

All female sockets shall have an interference fit with corresponding size pipe. Refer to Table 2

Component cut length dimension tolerances of ±.500"

Angle (change of direction tolerances of ±2°

Product Quality

All fitting welds (hand and machine) shall be 100% spark tested

Fiberglass reinforced fittings shall be as free as possible from visual defects such as foreign inclusions, air bubbles or delamination

Random inspection performed daily by floor supervisor

General Specifications for Standard Schedule 40 & Schedule 80 PVC Fabricated Pressure Fittings

Scope

This specification is applicable to fabricated fittings, as furnished by Harrison Machine & Plastic Corporation, as they pertain to (PVC) Polyvinyl Chloride Schedule 40 & Schedule 80 fitting configurations.

Materials of Construction

(PVC) Polyvinyl Chloride

Fittings are to be manufactured from PVC material which needs or exceeds the requirements of ASTM D-1784, cell classification 12454B, Type 1, Grade 1.

Pressure pipe used in fabrication must conform to ASTM D-1785 (Schedule 40/80) or ASTM D-2241 (SDR-26/41) and listed by the National Sanitation Foundation (NSF) for potable water applications.

Sheet stock material (where used) must conform to ASTM D-1784, cell classification 12454B, Type 1, Grade 1, normal impact, manufactured without the use of plasticizers or fillers.

Solvent Cement and Welding Rod (PVC)

All solvent cements used, conform to ASTM D-2564, listed by NSF for potable use applications.

Welding rod used in the manufacture of the above fittings, shall conform to ASTM D-1784, cell class 12454B for PVC, and shall be of a material compatible with the corresponding pipe/sheet stock.

Assembly/Construction Procedures

Fittings shall be Butt Fusion (machine) welded where feasible or hand welded (fillet welded) by qualified and experienced craftsman trained in the art of thermoplastic welding and fabrication.

All pressure fittings, with the exception of formed elbows, couplings, reducer couplings and reducer bushings will be 100% fiberglass reinforced with multiple layers or mat and resin to increase the base pressure rating of the fitting to meet or exceed the desired performance pressure rating of the corresponding diameter and wall Schedule of pipe. Refer to Table 1.

PVC Schedule 40 fittings will be white in color, while PVC Schedule 80 fittings will be dark gray in color. This color code applies to both pressure and drainage patterns.

Fitting diameters, 18", 20", & 24" as a customer option, may also e constructed from SDR-26 or SDR-41 pipe dependent upon the pressure rating required (i.e. 160 psi or 100 psi).

Dimensional Specifications

All cataloged fittings to be furnished in accordance with Harrison Machine and Plastic Corporation, published drawings. Non-cataloged fittings will be furnished in accordance to or as agreed upon customer specifications.

All female sockets shall have an interference fit with corresponding size pipe. Refer to Table 2

Component cut length tolerances of ±.500".

Angle (change of direction) tolerances of ±2°.

Product Quality

All fitting welds (hand and machine) shall be 100% spark tested

Fiberglass reinforced fittings shall be as free as possible from visual defects such as foreign inclusions, air bubbles or delamination

Random inspection performed daily by floor supervisor

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Solvent Cement Joining Recommendations (Large Diameter PVC Joints)

These quidelines specifically address recommended procedures required in successfully making solvent weld joints for large diameter systems (i.e. 8" through 24"). Solvent cemented joints represent the final important steps in making the system either a success or a failure. It is imporant that these instructions are carefully followed.

Important to all successful solvent weld joints there are "FOUR" important ingredients:

1. It is essential that surfaces to be cemented are clean and free of foreign matieral. If permitted to remain, grease, oil, ink, etc. can interfere with the solvent cementing process and reduce the strength of the bond.
2. Joining surfaces (pipe & fitting) must be dissolved and made soft.
3. Sufficient cement must be applied to fill gaps beween pipe & fitting.
4. Assembly of pipe & fitting must be made while the surfaces are both wet and fluid

Large diameter joints are very similar to those for smaller diameters, in that both have tapered sockets. Tapered sockets have the capability of providing a fused joint at the socket bottom and a bonded joint at the top of the socket, resulting in a quality seal particularly in pressure applications. Tapered sockets, however, also result in a situation wher ethe pipe will tend to "push-out" immediately after the pipe is inserted into the fitting socket. Care must be taken to hold the pipe in place until the cement begins to set.

As with any solvent cemented joints, the pipe must be cut square and cleaned. Large diameter PVC pipe may be cut with a skill-saw and a carbide tipped blade. A circular blade with 20 or less teeth is preferred over a finer blade with tends to heat the PVC material as it cuts, resulting in a molten PVC residue producing a rough cut. The use of a "pipe-belt" is recommended to ensure a straight cut.

After the pipe is cut to length, the outside and inside edges are to be deburred. This can be easily achieved by scraping these edges with a sharp edged piece of steel (i.e. file). This is a relatively easy step and only takes a few moments, but is a critical step.

Two or more pipe fitters are stongly recommended when making large diameter joints due to the bulk and weight of the system as well as the need to apply cement and primer as quickly as possible.

Align the pipe & fitting as close to its final position as possible. Elevate both the pipe & fitting so that the entire circumference is accessible.

Mechanical devices, such as come-alongs, are strongly recommended to pull the pipe into the fitting socket. The use of chains to "grasp" the pipe is an option but they may also slip. Sufficient cable or chain, enough to run the entire length of 20 foot joint(s) of pipe, must be laid out on either side of the joint, prior to assembly. Additional cable must be added in order to secure it to a 4x4 block, extending approximately 1 foot beyond the pipe on side. Cumbersome as it might appear, this method offers a more positive pull than other methods.

(Note: A chain sling may be used on the fittings providing it results in a "straight" pull.)

At this point, available manpower working in unison, is used to keep all components in place. Be sure the pipe & fitting are free to trasvel the required distance to seat at the fitting socket bottom. Mark the depth of the socket on the pipe, plus six inches, as an indication of pipe insertion depth. The two cable come-alongs are immediately hooked up at 3:00 and 9:00, so that after application of primer and solvent the joint may be pulled togeher.

When the chains (cables) are in place joint preparation now takes place.

PC-64 Primer-Cleaner, clean pipe and fitting surfaces with a cotton rag to remove any moisture and excessive dirt.

After properly cleaning pipe surfaces, using PC-64 Primer-Cleaner and a 3" to 4" wide brush, liberally apply the primer so that it flows on to and soaks into the plastic, resulting in a softening of the surfaces for maximum weldability. The primer should be applied to the pipe ends and to an area equal to the corresponding fitting socket depth plus approximately 4 inches. The primer will remove the glossy surface, dirt and surface printing. A properly primed surface will have a uniform dull surface which will beging to soften.

Prime the fitting socket in the same manner as described above. A second coating of primer may then be needed on the pipe to assure wet surfaces

Using Gray Medium-Body Cement, liberally apply the solvent, again using a 3" to 4" brush, to both the fitting socket and pipe surface. Do not overbrush the solvent. When done properly, very little of the surface areas, to be joined should be visible A thick even coat is needed to fill the gap between pipe & fitting.

Note: It may be advisable to pour the primer and solvent into larger "wide-mouth" containers, prior to use to accomodate the 3" to 4" brushes.

Important: It is advisable to utilize two or more pipe fitters. One will apply primer/solvent to the fitting socket and the other to the pipe surface, simultaneously and quickly. The joint surfaces must be fluid when making the joint.

Using the come-along, pull joint together, drawing the pipe into the fitting socket until the pipe has reached the fitting stop (socket bottom). Observe the previously measured pipe markings to ensure pipe that the pipe is seated. At this point, the cement will ooze toward the bottom of the pipe and fill a small section inside the fitting. Remove as much visible excess cement as can be reached. One very large diameter systems, "Do not venture inside the system to inspect the joint or to clean the solvent. The fumes can be dangerous."

Any excess solvent on the outside of the joint should also be removed, to avoid puddling and for appearance.

Continue come-along pressure, holding the pipe into the fitting socket for approximately 15 minutes (or until the solvent begins to set-up), to prevent the pipe from "pushing-out".

Pressure test the system only after the joints have cured. Refer to curing schedules as defined by the solvent manufacturer which are primarily dependent upon temperature.

The above are recommendations only. Site conditions vary greatly. Harrison Machine & Plastic Corporation cannot be held responsible for results.