Sewage pumps lake yell

Added: Apr 19, 2016 5:01 pm Modified: Apr 21, 2016 12:14 pmTrack Changes Amendment 0001 issued to include setting plan.



MINIMUM REQUIREMENTS

General

The contractor shall furnish Fairbanks Nijhuis or equal vertical close-coupled drypit pumping units as specified below. Pumps shall replace existing Fairbanks Morse Pumps. Contractor/Supplier shall identify any and all piping modifications that may be required to install new pumping units into the existing configuration. Submit with proposal representative drawings, estimated scope of work and bill of materials detailing proposed piping modifications. Pumps with impellers attached directly to shafts are unacceptable. Pumps are to be connected to the electric motor by a flexible coupling.

Service 1

Quantity: _3_

Basis of Design ¿ FN Model: 4¿B5443

(Each pump shall be capable of providing the following hydraulic conditions.)

Design Flow: 400GPM

Head: 108¿TDH

Pump Efficiency: 55% minimum

Maximum Pump Speed: 1800RPM

Maximum Nameplate Motor HP: 30HP

Driver to include: - 30 HP TEFC 1800RPM, 460V/60Hz/3Ph Motor, 1.15 SF ¿

- Altitude Corrected for 8,000¿ amsl

Minimum Shutoff Head: 140¿TDH

Maximum NPSHR at design: 12 FT



Service 2

Quantity: _3_

Basis of Design ¿ FN Model: 4¿B5443

(Each pump shall be capable of providing the following hydraulic conditions.)

Design Flow: 600 GPM

Head: 115¿TDH

Pump Efficiency: 64% minimum

Maximum Pump Speed: 1800RPM

Maximum Nameplate Motor HP: 40HP

Driver to include: - 40 HP TEFC 1800RPM, 460V/60Hz/3Ph Motor, 1.15 SF

- Altitude Corrected for 8,000¿ amsl

Minimum Shutoff Head: 140¿TDH

Maximum NPSHR at design: 25 FT

Rotation

They will be clockwise rotation when viewed from the driver end.

Impeller

Impeller shall be one piece, single suction, enclosed 2 vane, radial flow design with well-rounded leading vane edges and thick hydrofoil shape, which prevents the accumulation of solids and stringy material through the impeller. It is to be dynamically balanced and secured to the shaft by means of a key and fastener. Wiper vanes are not allowed. The impeller waterways and clearance between the impeller periphery and volute cutwater shall be capable of passing a 3¿ sphere. The impeller shall be adjustable by jacking bolts on the bearing housing, shims are not acceptable.

Volute/Casing

Volute shall be one-piece cast with flanged tangential discharge. Discharge flange shall be 125lb. ANSI drilling. Volute shall be designed to permit front and back impeller removal and be capable of rotation in increments to accommodate piping orientation independent of the base location. Diffusion vanes are not permitted. A contoured volute handhole for inspection and cleanout at the impeller as required. Nominal casing thickness is to be 1/2¿. Casing shall be hydrostatically tested to 1.5 times the design head of 1.25 time the shut-off, whichever is greater. Centerline discharge volute is not acceptable.

Base and Elbow

A rugged heavy duty fabricated steel base, with openings large enough to permit access to the suction elbow and cleanout bolted directly to the volute shall be provided. The vase shall be designed to support the assembled with of the pump and the driver. A cast iron suction elbow with 1-1/4¿ tap connection, handhole cleanout, and 125lb flat-faced flange conforming to ANSI drilling shall be furnished. A metal shaft guard completely enclosed the coupling will be provided. The coupling shall be a flexible type coupling manufactured by Falk or Woods (manufactures choice).



Backhead

Backhead shall be provided with an integrally cast sealing box. The sealing box is to accommodate a Double mechanical seal. Seal shall be provided with carbon vs. ceramic faces. Springs and hardware components shall be constructed of stainless steel. Flush water connections shall be provided for use with existing flush water system. Provisions are to be made for draining sealing box leakage.

Fits

Volute, suction, backhead and frame shall be manufactured with concentric shoulder fits to assure accurate alignment.

Shaft

The shaft shall be made from high quality steel, of sufficient diameter to carry the maximum load imposed and to prevent vibration and fatigue. The minimum shaft diameter between the bearings shall be 3.25¿. The torsional stiffness of the shaft shall be no less than 1.23 X 10**6 (in-lb/radian). Shaft is to be accurately machined along its entire length. A renewable 416 Stainless Steel, BHN of 450 ¿ 464 shaft sleeve, positive adhesive sealed, shall be protecting the shaft through the sealing box area.

Wear Rings

Stainless Steel, Axial type removable wear rings are to be provided on both the impeller and suction head. They shall provide a seal between the impeller and fronthead for reduction of recirculation. The impeller wear ring shall be approximately 50 Brinnell softer than the fronthead wear ring. Radial type or L type wear rings are not acceptable.

Frame

The bearing frame shall be of rugged, heavy-duty construction and line bored for accurate and permanent bearing alignment and bearing housings shall be dust proof.

Bearings

Radial (inboard) bearing shall be grease lubricated single row. Thrust (inboard) bearing shall be grease lubricated, angular contact duplex mounted bearings. Bearing to be designed for a minimum L10 of 100,000 hours while operating within the POR (preferred operating range) in accordance with AFBMA. Center to center distance shall be no less than 11¿.

Quality Assurance

Pumps are to be engineered and manufactured under a written Quality assurance program. The Quality assurance program is to be in effect for at least five (5) years, to include a written record of periodic internal and external audits to confirm compliance with such a program. All equipment preferably 100% manufactured in the USA.

Material Specification

Impeller Cast Iron A48-CL30

Shaft Steel A 108-C1141 or A332-C4140

Gland Half, interlocking Cast Iron A48-CL30

Volute Cast Iron A48-CL30

Fronthead Cast Iron A48-CL30

Backhead, frame Cast Iron A48-CL30

Frame Cast Iron A48-CL30

Bearing Housing Cast Iron A48 CL-30

Cover, bearing housing Cast Iron A48 CL-30

Housing, thrust Bearing Cast Iron A48 CL-30

Radial Bearing / Thrust Bearing Steel

Packing Synthetic packing, graphite impregnated

Key, coupling Steel A108 GR1018

Cover, handhole Cast Iron A48 CL-30

Base Cast Iron A48-CL30

Elbow Cast Iron A48-CL30

High Ring Base with Fabricated Steel

Coupling Guard