I'm going through the guide specifications (reference specs not tied to a particular project) and finding some curious things. One is that we are requiring a shaft sleeve to be used on centrifugal pumps that also have cartridge mechanical seals.
My impression was that since a cartridge...
I'm looking for a relationship between pressure and change in the enclosed volume of a pipe. I have the equations to generate radial, tangential, and longitudinal stresses. I had planned to use these values to get strains and convert that into a change in volume.
I am concerned that the radial...
I'm planning for a witnessed pump test at the factory. I haven't done a witnessed test before, so I would like to get some opinions on what to watch out for during this process. I don't expect the manufactuer or mfr's representative to do anything unscrupulous, but it's always possible, and so...
I got a request from a fellow engineer at the plant asking about doing a planned engineered lift per ASME B30.2. The hoist they want to use is rated for 3 tons (i.e. 6000 lbf), and the item they want to pick is 6100 lb.
ASME B30.2 3.2.1.1(a) says “Planned engineered lifts shall be limited to...
I'm working on a project to replace three large centrifugal sewage pumps. Among their many features are suction air injection ports. The existing pumps use air injection, but due to design changes with the new pumps, I'm not confident that the existing air flow rates will be appropriate for the...
I need to find the appropriate terms to describe some features of a sea water intake structure as it relates to the pumps.
The application is a powerplant using vertical, wet pit, mixed flow pumps for circulating water.
Some specifications need to be re-written because the use of "pump bay"...
I am a bit confused about horizontal, end suction, vertical discharge, centrifugal pump standards. The following discussion will be limited to this pump type.
These pumps are often categorized as ANSI or ISO pumps. The way ISO pumps are standardized is confusing to me.
I currently have access...
1. Will water emulsify in biodiesel or biodiesel / petro-diesel blends?
2. What methods are avaialable for removing water and water soluble minerals (i.e. sodium and potassium) from biodiesel or biodiesel / petro-diesel blends?
BACKGROUND INFORMATION
I am trying to determine what method of...
I need to get a vent system for a diesel tank figured out. It's approx 300,000 gal of 5% biodiesel. The fuel is expected to sit unused for long periods of time.
The tank is 40' dia & 32' high shell. The tank will be located in a coastal marine environment.
The tank is being designed for 2.5...
I am trying to decide if I can accept a vendor proposal to use a self priming centrifugal pump instead of a vane pump.
The application is for diesel unloading from trucks. Gravity draining is not an option. An air eliminator downstream of the pump will be used.
The concern I have is that the...
I'm working on a backup fuel system for a gas-turbine generation station. It's a set of natural gas fired turbines with HRSG, steam turbines, etc. The backup fuel is #2 diesel. Build stage one will have facilities for a test run (several hours) on liquid fuel. Build stage two will have...
I am trying to design a sanitary wastewater sump pump system. At the outlet from each of two buildings will be a sump with a grinder pump to transfer waste to a wastewater treatment system. Only kitchen, bathroom and shower waste will be included in this system. The treatment system is vendor...
I often find myself doing initial layouts for P&IDs. A lot of the time it's quicker & easier to do a pencil sketch of the system first. I've seen other people that have stencils to draw valves, flanges, control devices, etc, but I haven't found a source to get stencils like these for myself...
I'm trying to model a metal box sitting on the ground. It's 3" thick steel, painted white, and not insulated. It sits in the sun on a hot day with no wind and comes to steady state. Inside the box is a small heater.
The goal is to estimate the internal air temperature.
I've been trying to...
I have a copy of ASHRAE Handbook Fundamentals 2005. In it I've been using the relationships for sol-air temperature and heat flux. See page 30.22, equation 28.
q/A=alpha*E+h(Tambient-Tsurface)-epsilon*dR
h = coefficient of heat transfer by long wave radiation and convection on surface
E =...
How can I adequately calculate pressure drop in a line if viscosity is ~3000cP and Reynolds' number is under 10? When I look at a Moody plot, it doesn't seem to be anywhere near the plotted curves?
Using the common relation of 64/Re=f doesn't seem to be giving reasonable results either.
Based...
In sizing for critical flow of a relief device according to API 520 Part I section 3.6.2.1.1 the effective coefficient of discharge is described as follows:
"Kd= effective coefficient of discahrche. For preliminary sizing, use the following values:
=0.975 when a pressure relief valve is...
I am trying to configure/size some pressure relief devices in a gas plant. A new subsystem connects a low pressure loop (<10 psig) with a higher pressure (140 psig) set of tanks. In some situations, if valves are put in improper positions, it is possible to send gas from the high pressure tank...
I have a few brass bodied valves with threaded inlet connections. The inlet connections are leaking.
The application where they're used requires them to hold pressures of 0-300 psig at temperatures ranging from ambient to -200F.
I have not been able to confirm with the plant operators...
Can someone provide some examples of reliable and accurate thermocouple and thermowell configurations applied to piping? I am most interested in the mechanical layout and sizing as opposed to the interaction of the sensor and electronics.
I am aiming to minimize heat leak to the process fluid...
