C-2 Attachment 2-1 Amendment to spec 232113_13 Rev1.pdf

USDA Forest Service Underground Hydronic Piping 23 21 13.13

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SECTION 232113.13

UNDERGROUND HYDRONIC PIPING

PART 1 - GENERAL

1.01 SUMMARY

A. Section includes the following underground hydronic piping:

1. Preengineered cased piping system.

1.02 DEFINITIONS

A. Invert: Vertical distance from Project datum reference point to bottom interior pipe surface.

1.03 ACTION SUBMITTALS

A. Product Data: For the following:

1. Preengineered cased piping system components.

B. Shop Drawings: For underground hydronic piping. Signed and sealed by a professional engineer.

1. Site plan of piping layout with details for building connections, branch connections, anchors and expansion joints

2. Include calculations showing requirements for expansion compensation for underground piping.

3. Show expansion compensators, offsets, and loops with appropriate materials to allow piping movement at required locations. Show anchors and guides that restrain piping movement with calculated loads, and show concrete thrust block dimensions.

4. Show pipe sizes, locations, inverts, and pitch. Show piping in trench, piping in conduit, and cased pipe with details showing clearances between piping.

5. Show insulation thickness.

1.04 QUALITY ASSURANCE

A. ASME Compliance: Comply with ASME B31.9, "Building Services Piping," for materials, products, and installation.

PART 2 - PRODUCTS

2.01 PERFORMANCE REQUIREMENTS

A. Provide components and installation capable of producing hydronic piping systems with the following minimum working-pressure ratings:

B. Heating Piping: 100 psig at 200 deg F.

2.02 PREENGINEERED CASED PIPING SYSTEM

A. Description: Factory-fabricated piping with carrier pipe, insulation, and casing.

B. Source Limitations: Obtain piping system from single source from single manufacturer.

C. Carrier Pipe

1. Drawn-Temper Copper Tubing: ASTM B88, Type K.

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2. Wrought-Copper Fittings: ASME B16.22.

3. Brazing Filler Metals: AWS A5.8M/A5.8, BCuP Series, copper-phosphorus alloys for joining copper with copper; or BAg-1, silver alloy for joining copper with bronze or steel.

D. Carrier Pipe Insulation: Polyurethane foam insulation injected with one shot into the annular space between carrier pipe and jacket. Insulation shall be rigid, 90% closed cell with a minimum 4.0 lbs per cuft density, compressive strength of 55 psi @ 75˚F, a thermal conductivity initial and aged K factor no higher than 0.14 @ 75˚F per ASTM C-518 and an E84 25/50 passive fire resistance rating.

E. Casing: HDPE pipe manufactured from PE4710 resin conforming to ASTM D3350.

Minimum wall thickness of 0.18-inches.

F. Casing accessories include the following:

1. Joint Kit: Half-shell, pourable or split insulation, casing sleeve, and shrink-wrap sleeve.

2. Expansion Blanket: Elastomeric foam, formed to fit over piping.

3. End Seals: Shrink wrap the casing material to seal watertight around casing and carrier pipe.

G. Source Quality Control: Factory test carrier pipe to 150 percent of operating pressure of system. Furnish test certificates.

PART 3 - EXECUTION

3.01 PIPING INSTALLATION

A. Drawing plans, schematics, and diagrams indicate general location and arrangement of piping systems. Indicate piping locations and arrangements if such were used to size pipe and calculate friction loss, expansion, pump sizing, and other design considerations. Install piping as indicated unless deviations to layout are approved on coordination drawings.

B. Remove standing water in the bottom of trench.

C. Bed the pipe on a minimum 6-inch (150-mm) layer of pipe system manufacturer's recommended granular fill material with a minimum 6-inch (150-mm) clearance between pipes.

D. Do not backfill piping trench until field quality-control testing has been completed and results approved.

E. Install piping at uniform grade of 0.2 percent. Install required fittings to accommodate capped drains at low points and elsewhere as required for system drainage. Install capped manual air vents at high points.

1. Maintain continuous bedding under piping. Do not leave gaps in pipe bedding, allowing pipe to sag between contact points with the bedding.

F. In conduits, install drain valves at low points and manual air vents at high points.

G. Install components with pressure rating equal to or greater than system operating pressure.

H. Install piping in straight lines. Do not bend pipe.

I. Install fittings for changes in direction and branch connections.

J. Secure anchors with concrete thrust blocks.

K. Secure anchors and fittings where piping changes direction, and where elsewhere required by manufacturer's written installation instructions, with concrete thrust blocks.

Jim Rehfeldt Polygon

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3.02 JOINT CONSTRUCTION

A. Join pipe and fittings in accordance with the following requirements and Section 232113 "Hydronic Piping":

1. Ream ends of pipes and tubes and remove burrs. Bevel plain ends of steel pipe.

2. Remove scale, slag, dirt, and debris from inside and outside of pipe and fittings before assembly.

B. Brazed Joints: Construct joints in accordance with AWS's "Brazing Handbook," Ch. 35, "Pipe and Tubing," using copper-phosphorus brazing filler metal complying with

AWS A5.8M/A5.8.

3.03 IDENTIFICATION

A. Install continuous plastic underground warning tapes during backfilling of trenches for underground hydronic piping. Locate tapes 6 to 8 inches (150 to 200 mm) below finished grade, directly over piping. See Section 312000 "Earth Moving" for warning-tape materials and devices and their installation.

3.04 FIELD QUALITY CONTROL

A. Perform tests and inspections with the assistance of a factory-authorized service representative.

B. Tests and Inspections

1. Prepare hydronic piping for testing in accordance with ASME B31.9 and as follows:

a. Leave joints, including welds, uninsulated and exposed for examination during test.

b. Isolate equipment and instrumentation. Do not subject equipment and instrumentation to test pressure.

c. Install relief valve set to relieve at pressure no more than one-third higher than test pressure.

d. Fill system with water. Where there is risk of freezing, perform testing with air or liquid that will not freeze or cause damage to piping system materials.

e. For hydrostatic testing, install vents at high points to release trapped air while filling system. Remove test liquid at accessible low points.

2. Test hydronic piping as follows:

a. Subject hydronic piping to hydrostatic test pressure that is not less than 1.5 times system design pressure.

b. After hydrostatic test pressure has been applied for 10 minutes, examine joints for leakage. Remake leaking joints using new materials and repeat hydrostatic test until no leaks exist.

c. Do not pressurize carrier pipe with air.

d. Maintain test pressure for four hours with no loss of pressure.

3. Test conduit as follows:

a. Subject conduit to 15-psig (105-kPa) compressed air for four hours with no loss of pressure. Repair leaks and retest.

C. Piping will be considered defective if it does not pass tests and inspections.

D. Prepare test and inspection reports.

E. When successful testing is complete, flush carrier piping to remove dirt or debris remaining after construction. Drain piping after flushing is complete.

F. Fill underground piping system with permanent system liquid prior to system testing and balancing.

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END OF SECTION 232113.13

G. Source Quality Control: Factory test carrier pipe to 150 percent of operating pressure of system. Furnish test certificates.

B. Brazed Joints: Construct joints in accordance with AWS's "Brazing Handbook," Ch. 35, "Pipe and Tubing," using copper-phosphorus brazing filler metal complying with AWS A5.8M/A5.8.