CADMEP
Mechanical
- Sep 30, 2015
- 1
Hello all, from Maryland. New to the forum. I am not an engineer but have worked in the mechanical field for over 10 years, including systems controls, actual field installation, and am now in Project Coordination using AutoCAD, Revit, and Navisworks. One of the jobs we are working on is a new Middle School in Virginia but there's a slight problem.
Refer to the attached image M401_Controls and M012 Detail 10. The Cooling Tower in this Open Loop System, sits on a 6" concrete pad outside of the building, with rails and vibration isolation as scheduled.
The CTS/R piping is run underground to the Cooling Tower but as it enters the building, raises up to 7' 9" Bottom of Supply Pipe (the pipe elevation will likely have to be lowered).
The outlet of the Sump sits at approx. 26" AFF.
CTP-1A & B both sit on 4" hskping pads, 12" Inertia Bases, placing the inlet of the Suction Diffuser to each at approx. 36" AFF.
Even if we didn't follow the Detail (refer to M012_Detail 1) and placed a LR 90 Elbow (Sch 40 Weld) directly on the diffuser, creating more than 40" AFF meaning the Cooling Tower would require a work platform which is not in our scope.
An RFI has been written, a response received and the Engineer wants us to design the steel for the Cooling Tower (We are not Structural Engineers) to raise it higher and prevent pump cavitation.
My question is, can a Suction Diffuser be turned on its side and the pipe run low to the ground, and if so, would the low pipe be considered a trip hazard at approx. 28" AFF?
Also, shouldn't the ADS-CT be placed before the pumps?
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443621424/tips/M301_Enlarged_Mechanical_Room_Plans_u7uedj.pdf[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443622982/tips/M012_Detail_1_afapuj.pdf[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443622993/tips/M012_Detail_10_ccerqt.pdf[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443623007/tips/M401_Controls_xtijol.pdf[/url]
Refer to the attached image M401_Controls and M012 Detail 10. The Cooling Tower in this Open Loop System, sits on a 6" concrete pad outside of the building, with rails and vibration isolation as scheduled.
The CTS/R piping is run underground to the Cooling Tower but as it enters the building, raises up to 7' 9" Bottom of Supply Pipe (the pipe elevation will likely have to be lowered).
The outlet of the Sump sits at approx. 26" AFF.
CTP-1A & B both sit on 4" hskping pads, 12" Inertia Bases, placing the inlet of the Suction Diffuser to each at approx. 36" AFF.
Even if we didn't follow the Detail (refer to M012_Detail 1) and placed a LR 90 Elbow (Sch 40 Weld) directly on the diffuser, creating more than 40" AFF meaning the Cooling Tower would require a work platform which is not in our scope.
An RFI has been written, a response received and the Engineer wants us to design the steel for the Cooling Tower (We are not Structural Engineers) to raise it higher and prevent pump cavitation.
My question is, can a Suction Diffuser be turned on its side and the pipe run low to the ground, and if so, would the low pipe be considered a trip hazard at approx. 28" AFF?
Also, shouldn't the ADS-CT be placed before the pumps?
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443621424/tips/M301_Enlarged_Mechanical_Room_Plans_u7uedj.pdf[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443622982/tips/M012_Detail_1_afapuj.pdf[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443622993/tips/M012_Detail_10_ccerqt.pdf[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1443623007/tips/M401_Controls_xtijol.pdf[/url]