SigmaFire Installation Manual, rev. F - Clayton Industries

Section II - General InformationBHPMake-upValveTable 2-3: Makeup water valve and pipe sizesMinimumLine SizeBHPMake-upValveMinimumLine SizeBHPMake-upValveMinimumLine Size(in.) (in.) (in.) (in.) (in.) (in.)25 3/4 3/4 150 3/4 1 500 1 1 1/235 3/4 3/4 200 3/4 1 1/4 600 1 1 1/250 3/4 3/4 250 1 1 1/4 700 2 275 3/4 3/4 300 1 1 1/4 1200 1 1/2 2100 3/4 1 350 1 1 1/4 1600 2 2 1/2125 3/4 1 400 1 1 1/4 2000 2 3Note 1: All models use a makeup water solenoid valve.Note 2: Water flow is based on 44 lb. per hour per bhp (boiler horsepower).2.8 FEEDWATER SUPPLY REQUIREMENTSThe feedwater supply line sizing will be a minimum of one line size larger than the inlet connectionsize of the Clayton feedwater pump. Fractional dimensions will be rounded up to the larger whole-sizeddimension.NOTEClayton, like all OEMs, takes advantage of the limited length and lower velocities tominimize its internal line sizes. Like most manufacturers, this works well on Clayton’sinternal piping and pump head designs because of the very short equivalent pipelengths and quickly dividing flows (lower velocities) within our pump designs, whichyield lower velocities and acceleration head.Unfortunately, the customer and installing contractor experience the reverse whendesigning their feedwater piping system as they are usually faced with much longerequivalent length pipe runs and/or have to deal with a pipe required to carry morethan one generator’s flow. Therefore, it is critical for the installation designer to increasesupply line sizes to meet Clayton’s requirements for velocity and accelerationhead. See paragraph 2.8.2 and 2.8.3.2.8.1 Multi-unit SystemsA common design mistake is the installing of a single feedwater supply line to a common suctionheader for multiple reciprocating PD pumps. The preferred feedwater line design is providing each reciprocatingPD pump with its own supply line and suction header.04/21/2015 2-17 Sect02_Genrl-SF_q.fm