SECTION 15588 NATURAL GAS SYSTEMS

This spec was part of the Des Plaines, IL River WRF project that bid Feb 26, 2015.


SECTION 15588 NATURAL GAS SYSTEMS
PART 1 - GENERAL

1.1 SUMMARY

A. Extent of work is limited to piping and accessories as required to extend natural gas line from meter to gas fired equipment as indicated on drawings and schedules as required by this section.

B. Contractor to verify Gas Pressure available with local natural gas utility and to provide piping system including gas pressure step down regulators as may be needed.

1.2 REFERENCES

A. National Fire Protection Association (NFPA):

1. Standard 54 (ANSI Z223.1) National Fuel Gas Code (An American National Standard)


PART 2 - PRODUCTS

2.1 MATERIALS AND PRODUCTS

A. General: Provide piping materials and factory fabricated piping products of sizes, types, pressure ratings, and capacities as indicated. Where not indicated, provide proper selection as determined by Installer to comply with installation requirements. Provide materials and products complying with NFPA 54 where applicable, base pressure rating on natural gas piping system maximum design pressures. Provide sizes and types matching piping and equipment connections; provide fittings of materials that match pipe materials used in natural gas systems. Where more than one type of material or product is indicated, selection is Installer's option.

2.2 BASIC PIPES AND PIPE FITTINGS

A. Building Distribution Piping

1. Pipe Size 2 inches and Smaller:  Black steel pipe; Schedule 40, malleable iron threaded fittings.

2. Pipe Size 2½ inches and Larger:  Black steel pipe:  Schedule 40; wrought steel butt-welding fittings.

B. Gas Piping (Underground)

1. Exterior underground gas piping shall be MDPE pipe Driscoplex 6500 Series by Performance Pipe, a Division of Chevron Phillips Chemical Co, LP, Gastite, or

equal. Transition from plastic to steel shall be made underground with a heat fusion seal using either a coupling fitting or butter fusion seal. Install pressure test in accordance with standards set by the local utility.

2. Provide tracer tape with all buried none metallic natural gas piping to allow for utility locating for future.

2.3 SPECIAL VALVES

A. General: Special valves required for natural gas systems include the following types:

1. Gas Cocks:
a. Gas  Cocks  2  inches  and  Smaller: 150  psi  non  shock  WOG,  bronze straightway cock, flat or square head, threaded ends.
b. Gas Cocks 2½ inches and Larger:   125 psi non shock WOG, iron body bronze mounted, straightway cock, square head, flanged ends.

2. Pressure Regulators:   Step down pressure regulator, lock-up type staging type, reduction & capacity as required.

B. Manufacturer:  Subject to compliance with requirements, provide gas cocks of one of the following:

1. NIBCO, Inc.

2. DeZurik Corporation

3. Jenkins Bros.

4. Lunkenheimer Company

5. Rockwell International, Flow Control Division

6. Stockham Valves and Fittings

7. Walworth Company


PART 3 - EXECUTION

3.1 INSTALLATION OF NATURAL GAS PIPING

A. Use sealants on metal gas piping threads that are chemically resistant to natural gas. Use sealants sparingly, and apply to only male threads of metal joints.

B. Remove cutting and threading burrs before assembling piping.

C. Do not install defective piping or fittings. Do not use pipe with threads that are chipped, stripped or damage

D. Plug each gas outlet, including valves, with threaded plug or cap immediately after installation and retain until continuing piping, or equipment connections are completed.

E. Install  drip  legs  in  gas  piping  where  indicated,  and  where  required  by  code  or regulation.

F. Install "tee" fittings with bottom outlet plugged or capped, at bottom of pipe risers.

G. Install piping with 1/64 inch per foot downward slope in direction of flow.

H. Install piping parallel to other piping, but maintain minimum of 12 inch clearance between gas piping and steam or hydronic piping above 200 deg F.

I. Install gas pressure regulator at equipment. Size for pressure leaving meter, required pressure at equipment and required flow. Vent per code to atmosphere. NOTE: Coordinate gas pressures provided and placement of step down regulators where they may be required.

J. All pipe supports to be spaced a maximum of 5 feet.

3.2 GAS SERVICE

A. General:  Coordinate with local gas Utility Company the modifications to the existing Natural Gas service (s).

1. Coordinate available gas pressure and additional gas load being added to the existing service(s).

2. Coordinate any required meter change outs or upgrades if needed.

3. Consult with Utility as to extent of its work, costs, and fees associated with any service size increases or modifications. Pay such costs and fees.

4. Verify pressure leaving the meter. Gas piping distribution system was sized based on the indicated pressure leaving the meter or at the building structure as shown on the plans. If needed modify the gas pipe size based on actual pressures being provided.

B. Provide step down gas regulators as required at each structure and as may be needed at each natural gas burning device/equipment.

3.3 INSTALLATION OF PIPING SPECIALTIES

A. Do not conceal any gas piping or specialties.

3.4 INSTALLATION OF VALVES

A. Gas Cocks:  Provide at connection to gas train for each gas fired equipment item and on risers and branches where indicated.

B. Locate  gas  cocks  where easily accessible,  and  where they will  be  protected from possible injury.

3.5 EQUIPMENT CONNECTIONS

A. General:  Connect gas piping to each gas fired equipment item with drip leg and shutoff gas cock.

1. Comply with equipment manufacturer's instructions.

2. Install any required Step-down pressure regulators that may be required based on gas pressures supplied from gas meter to gas pressure requirements of equipment. Pipe any regulator vents to outside of building away from any O.A. intakes.

3.6 FIELD QUALITY CONTROL

A. Piping Tests:  Inspect, test, and purge natural gas systems in accordance with NFPA 54.

3.7 ADJUSTING AND CLEANING

A. Cleaning and Inspecting:  Clean and inspect natural gas systems.  Paint gas piping per Section 15526

END OF SECTION