Hello! This is a repeat post, to help answer at least one question that I had in this post. For the ASHRAE VRP calculator, the calculation is broken up by zones, and these zones must be classified as one type or another. If I have a zone that is actually a combination of rooms/spaces with...
The only other thread that I could find on this topic is here. I have a tank that is used to store water for pumped non-potable use. The tank's rough dimensions are 8ft in diameter and roughly 10ft in depth (cylindrical shape). Approximately 1ft from the bottom I have a outlet for the tank that...
This is more or less a follow-up to my previous post (thread507-523158), but maybe understanding this point will help me understand the other point. On the one detail for typical joist construction for this project, I see that the first pan is variable dimension ('30", 20", 15" or 10" pans as...
Hello all! Another question from a ME with little experience in structural engineering. For drawings from the early 1970's in the southeastern U.S., how were concrete joist spans dimensioned? I can figure the span length from the distance from beam to beam, but from the top to the bottom of the...
Does anyone here know if there are any useful tables (International Fuel Gas Code maybe?) or methods to calculate BTU or CFH loads from turrets in laboratories? Honestly, any design guide resources on determining natural gas loads would serve me very well. I'm at a loss when sizing natural gas...
Hello all, I've got another Revit modeling question as regards a structural footing. A note in the drawing (from 1968) specifies that:
"The maximum wall footing ste-off shall be 2'-0" vertical spaced not less than 4'-0" o.c. Footing step-offs are indicated on plans by the symbol...
One of my customer recently insisted on using Propress instead of soldered Type L copper. I think it was run with primarily because of how quickly it could be installed. Is this kind of technology reliable and proven? I work on an old university campus, so ideally I like to specify products and...
I am trying to model the loss coefficient (Cv or K value) through a non-slam wafer check valve (as it's specified in my job). I see that there are a few different types of check valves that Crane's TP-410 paper provides loss coefficients for the following valves. I used a 8" size for the...
Good afternoon struct-e's. I'm looking at a schedule of columns and footings for a building built in 1968, and trying to model the footings in Revit. For the footings, one of the rows indicates the "DEPTH W/OUT PL." [Depth without PL] Does anybody know what this means? Piling maybe? I don't see...
This is probably going to get me some links to other posts, mil-spec's and standards, but can anyone define the difference creation, use and alloy-wise between black steel and carbon steel? I've heard they are different, but as far as my understanding goes, black steel is just a kind of carbon...
I think I've got a good grasp on what valve authority is for individual circuits and how to apply it for designing & selecting AHU/FCU coil valves, but I cannot seem to find good guidance specifically for valve authority for variable primary and variable secondary systems. I got a full hydraulic...
Hello all! I'm wondering if anyone has knowledge or has created a specification that's related to nameplates on equipment that is supposed to be insulated. Haha, I have been frustrated in trying to get old equipment information off of anything connected into our chilled water system, and I'm...
Before I start, I want to mention that this forum thread was very helpful to understand what other engineers do to handle lab pressure.
I wanted to reach out see if there was a chapter or resource somewhere that guides a mechanical engineer through laboratory envelope design. I work with...
Hey everyone!
Got another question for the community. I am replacing two pumps (not headered) for two chiller pumps. The only graphic I've found anywhere that shows the kind of system I am working with is here. The fifth system described in this JMP article is nearly the same kind of system I...
Hey everyone,
I'm stuck on a laboratory renovation determining which code from IMC 510 (Hazardous Exhaust Systems) is applicable. Per the exception listed for labs:
"Exception: Laboratories, as defined in Section 510.1, except where the concentration listed in Item 1 are exceeded or (emphasis...
Hey everyone,
I've got a question about a piece of code from the 2018 International Mechanical Code (IMC). Section 510.6.5 states for makeup air for hazardous exhaust systems that:
Makeup air shall be provided at a rate approximately equal to the rate that air is exhausted by the hazardous...
Does anyone know if there are any rule of thumb Cv values for any steam traps? I.e. let's say I've got a float & thermostatic trap that's being used to drain a leg of cooled condensate. I'm trying to calc how long the leg will take to drain.
Been scratching my head far too long on this issue. I have a model of my campus chilled water district system in Pipe-Flo. Everything is currently modeled at the same elevation. When I generate the system curve vs. pump curve I get the following graph:
I've been reading in open system with...
I'm sure this is very obvious to most, but for some reason, I have struggled to understand this. For calculating valve authority N=ΔPv/(ΔPv+ΔPc) where ΔPv is the pressure drop across the control valve when fully open, and ΔPc is the pressure drop across the circuit, what part of the hydronic...
I've been using the software Pipe-Flo to build and analyze piping networks. A part of their program allows you to input pump curves supplied by the manufacturer. I was wondering - is this a feature that is unique to the software I am using, or is there is a standard/convention for electronic...
