Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. gt5879c

    How wet is too wet for drip field installation

    My drip field property is pretty steep over most of the site (>30%). There has been rain or snow 2 days out of every week for the last month. The contractor is chomping at the bit to begin installation of the drip field, but it's just too wet. He is asking how wet is too wet for installation? He...
  2. gt5879c

    Drip Disposal System

    Thanks for the advice. I've never used a PD pump before. Who makes them for applications like this? Also, if I were to use the Orenco pumps, how would I place them in series?
  3. gt5879c

    Drip Disposal System

    I have designed a drip disposal system on a 36,000 gpd system. Because the system is on a hillside and the static head is pretty high, I would need a pump with very high head. I'm talking 200 FT TDH an 70 gpm. I am having trouble finding a suitable pump. I had intended to use Orenco effluent...
  4. gt5879c

    Tapping Valve Sacrifice?

    I was once told by a senior engineer that when you install a tapping sleeve and valve to hot tap a force main, you have to install another valve, like a plug valve, because you have to sacrifice the tapping valve. I can't remember why? Any ideas?
  5. gt5879c

    Are Push-on Joints OK for Force Mains?

    I'm not sure I understand what you mean by this: "You need to down rate the PVC pressure rating for long term response." Can you please elaborate? Thanks.
  6. gt5879c

    Are Push-on Joints OK for Force Mains?

    Is PVC DR 17 with push-on joints OK for a STEP force main system with pressures up to 180 PSI. I know the pipe is OK, but are the joints able to withstand pressures that high?
  7. gt5879c

    Manifold Force Mains

    I have designed a manifold force main before. It had two pump stations on one force main. I used the graphical method where you plot the pump curves, modified pump curves and system curve for the common force main section, but I need to design one with three pumps. I don't know how to go about...
  8. gt5879c

    Why horizontal distance on Gravity Sewer Profiles?

    I've wondered this for a while. Why do most engineers label horizontal distance on sanitary sewer profiles rather than the slope distance? I know that if you label the slope distance it will actually be the actual length of pipe, but it won't match the stationing. But is it really necessary for...
  9. gt5879c

    How to determine Q of existing well

    Is there a way to determine the flow rate of an existing water well? I need to build a model of an existing water system supplied by 6 wells. I obtained the well numbers from the casing and called the well driller, but they do not have any information on the output of those wells. Is there any...
  10. gt5879c

    NPSHA

    I am bit confused on the NPSHA calculation. The equation I am using is this: NPSHA = Ha +/- Hst - Hf - Hvp Where, Ha = ambient pressure Hst = static head from liquid surface to pump centerline Hf = friction loss a entrance through piping/fittings Hvp = vapor pressure Ok, so I know on suction...
  11. gt5879c

    Wastewater Characteristics of a Truck Wash/Service Facility

    Tom, is this still an issue if we have an oil/water separator upstream of the treatment plant?
  12. gt5879c

    Peak rate factor

    You can calculate one based on flow rate as follows: PF = 3.81(ADF^-0.16) for maximum instantaneous flow rate PF = 2.28(ADF^-0.12) for maximum 24-hour flow rate ADF is Average Daily Flow in MGD
  13. gt5879c

    Wastewater Characteristics of a Truck Wash/Service Facility

    Hello All, I am designing a decentralized wastewater system for a truck wash/service facility. This facility will service and wash over the road trucks and trailers for a national carrier. There will also be a couple of restrooms and a kitchen facility in the building. I am thinking that the...
  14. gt5879c

    OK to pipe clearwell overflow to plant influent?

    Yes it is a filter plant. The backwash water goes to a pond. I was thinking if we piped the clearwell overflow to the raw water wet well, we would have to put in a check valve to keep raw water from entering the clearwell. I would also be discharging the pipe in the wet well above the emergency...
  15. gt5879c

    OK to pipe clearwell overflow to plant influent?

    I have a situation where the design engineer provided a clearwell overflow box on the side of the clearwell at ground level (the clearwell is below grade), but the owner wants to pipe it somewhere rather than have the water just flow out on the ground. Can I pipe this to the influent raw water...
  16. gt5879c

    Valves in Wastewater Pump Station

    Hello all, What are the pros and cons of using a plug valve or a gate valve in a pump station valve pit (in addition to the check valve). I've always used plug valves for my isolation valve, but my new employer always uses gate valves. Is either better than the other? Please advise. Thanks Chris
  17. gt5879c

    How to learn billing?

    I am a project manager at a firm and still have not had the opportunity to learn project billing. I manage all aspects of the project, but my boss still does all the billing. I have repeatedly asked to be brought in on this, but he hasn't done it. Are there any books or seminars one could attend...
  18. gt5879c

    Stormwater Outfall - Definition??

    I've come across a discrepancy in the definition of a Stormwater Outfall. GA Env. Protection Div. says its the outlet of any stormwater conveyance system. But people have told me ASCE defines it as the stormwater conveyance system itself - not just the outlet, like an outfall sewer. What is the...
  19. gt5879c

    How to transition from PVC Force main to HDPE force main?

    CivEnvEng98: What is your 11.25 bend for? Why is the air release valve necessary? Thanks
  20. gt5879c

    How to transition from PVC Force main to HDPE force main?

    I have an 8" force main that is PVC that I need to transition to HDPE in order to do a directional drill for a section. How would I transition this pipe from PVC to HDPE and back? What type of coupling or transition collar?
Back
Top