(A) General.
(1) All internal transmission piping shall conform to A.S.T.M. A-53 (CW) for nominal pipe size four-inch and smaller and A.S.T.M. A-53 (ERW) Grade B for nominal pipe size five-inch and larger. Butt welded fittings shall conform to A.S.T.M. A-106. Forged steel flanges shall conform to A.S.T.M. specification A-181, Grade 1 and ASA B16.5.
(a) Size ten-inch and below: Schedule 40; and
(b) Size 12-inch and above: standard weight (.375-inch wall).
(2) The piping configuration shown is for illustrative purposes, however, the piping sizes below are the minimum allowable:
(a) Suction inlet: eight inches;
(b) Suction header: eight inches;
(c) Suction piping: six inches;
(d) Discharge piping: six inches;
(e) Discharge header: eight inches; and
(f) Discharge outlet: eight inches.
(B) Butterfly valves.
(1) The isolating valves used throughout the equipment capsule will be of the wafer design. The body of each isolating valve will be constructed of cast iron A.S.T.M.-126 and be equipped with a minimum of four alignment holes with which to pass mating flange studs so as to assure proper butterfly alignment within the piping system. The valve disc will be constructed of bronze A.S.T.M.-B148-9C and be machined to close tolerances on both the flats and O.D. to assure drop tight shut off and reduce operating torque. The valve stems will be constructed of phosphate coated carbon steel A.S.T.M.-108 Grade 1040 and the stem bushings will be non-metallic. The disc will be affixed to the shaft by a pair of taper pins. The valve seat will be phenolic backed EPDM resilient seat designed to be easily field replaceable.
(2) Valve sized six inches and smaller shall be equipped with lever operator and ten-degree increment throttling plate. Valve sized eight inches and larger shall be equipped with a weatherproof, heavy duty, gear operator complete with a position indicator.
(3) The butterfly valves for Pump 3 are to be included in the piping.
(C) Compression couplings.
(1) Each pump suction and discharge pipe shall include a compression type, flexible coupling to prevent binding of the pump, pump suction or control valve. Each coupling shall consist of two follower rings, a flared middle ring with end flares generous enough to provide adequate gasket seat areas, two resilient rubber gaskets and steel bolts. The coupling when installed shall provide a permanent, leak-proof, flexible installation.
(2) In lieu of a compression coupling, a restrained, removable flange such as Uni-Flange or a flanged coupling adapter (FCA) may be used to relieve strain on a pump or control valve. The flanged coupling adapter will be of the same manufacturer as the compression couplings used elsewhere in the equipment capsule and shall be a regular product of that manufacturer. Flanged coupling adapters shall be complete on the flanged end with an integral rubber flange gasket and on the open end with a triangular section rubber follower gasket and follower ring. Bolts for the flanged coupling adapter will be individual to the FCA and be supplied with the FCA.
(D) Pressure gauges.
(1) All pressure gauges within the booster pumping station shall have four and one-half inch minimum diameter faces. The case shall be black, flanged back type with close type ring and clear glass face. The gauge connections shall be at the bottom of the gauge and will be one-fourth inch NPT. The gauge internal construction shall include phosphor bronze bourbon tube with a brass movement, bronze bushed independently mounted. Pressure gauge range and scale graduations shall be in feet of water and psi as follows:
(a) Inlet pressure: zero to 100 psi, ten psi figure intervals, with graduating marks every one psi; and
(b) Outlet pressure: zero to 160 psi, 20 psi figure intervals, with graduating marks every two psi.
(2) All gauges will be panel mounted or fixture mounted off the pipeline or sensing point and be flexible connected to their respective sensing point. Gauges may be mounted singularly in tandem or in any organized combination. The gauge trim tubing shall be complete with both isolating and vent valves and the tubing shall be so arranged as to easily vent air and facilitate gauge removal. Gauges mounted directly to the pipeline or sensing point will not be accepted.
(E) Automatic pump check valves.
(1) The automatic pump check valves shall be of the electrical, double cushioned type and shall have a cast iron body and cover, angle pattern, with all bronze trim. The valves shall be faced, flanged and drilled to conform to 125# ANSI standards and shall be sized as shown in the plans.
(2) The valves shall be of either the piston or diaphragm type. If the piston type, the valve shall have an all bronze liner with V-port openings. The piston shall also be of bronze and be equipped with an indicating rod. If of the diaphragm type, the diaphragm assembly shall be fully guided top and bottom. The valve shall be spring-loaded to assure operating differential.
(3) The design of the valve shall be such as to provide air and water cushioning to prevent hammer and shock. Speed of valve opening/closing shall be adjustable by hand-operated regulating valves. Wear on the valve moving parts shall be absorbed by renewable leather or rubber cups and seat. The valve shall be designed to provide full pipe line flow when in the open position and shall shut off drop tight, when closed.
(4) The automatic pump check valves shall provide normal automatic opening and closing function, plus emergency closing on electrical outage. The valve will also provide a manual control to open the main valve.
(5) The automatic pump check valves will be provided with an all bronze sustaining pilot. This pilot will be of the diaphragm operated, spring loaded, balanced type, providing an adjustable spring range of minimum of 70 psi. The pilot device will sense suction header pressure and throttle the main valve to maintain suction pressure. Should suction header pressure drop below minimum value, the sustaining pilot shall override the electrical controls and close the automatic pump check valve.
(Ord. passed 6-21-2011)