Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

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

Search results for query: *

  1. DAlbertson

    Problem of air pressure regulator with enormous turn-down

    I'm building a test jig that needs an air pressure regulator with a very large turn-down: Inlet pressure range = 80 to 120 psig Discharge pressure range = 1 to 130 inches of water (0.036 to 4.7 psig) Discharge flow rate demand = 0 to 150 CFM, with the maximum d(flow)/dt = 800 CFM/s I've sent...
  2. DAlbertson

    Viton O-ring deformation model for simple partially-restrained axial seal

    I have a 5/8" orifice solenoid valve controlling room air with a differential pressure varying between 0.1 psi and 5.0 psi. Attached to this post is a sketch of the valve: Open, Closed, section Closed, and detail of o-ring Closed. Even though the pressures are very low and the resultant force...
  3. DAlbertson

    Production welding aluminum parts with flash-butt or resistance-butt

    My company is designing a production line for a new product. Two of the parts are aluminum near-mirror images of each other, and were to be assembled with adhesive. The customer change-ordered the fabrication to be welded instead. Sketches of one of the two parts is shown below. The...
  4. DAlbertson

    Bond overcoats on magnetic wire - electrical heat sealing?

    Hacksaw, Thank you for your comment! You're right, a tray of bobbins going through an oven might be the simpler solution anyway. Any thoughs on the quality of bond produced by the polyvinyl butyral overcoat versus vacuum infusion with varnish or epoxy? Thank you again, David
  5. DAlbertson

    Bond overcoats on magnetic wire - electrical heat sealing?

    I'm winding a set of coils from 37 AWG magnet wire with a single-thickness polyurethane/nylon combination insulation (NEMA MW29-C) and a bonding overcoat of Polyvinyl Butyral. The bond overcoat can be made liquid with either Isopropyl Alcohol or heat. If heating, then a temperature of 110 C to...
  6. DAlbertson

    Damping collision of low-mass actuator

    Greg and Mike, Thank you very much for your answers! Greg, your comments about the spring mass damper equation producing results that could be interpreted in the frame of material properties and your suggestion to bracket the problem in the lab (a divide-and-conquor approach) are very well...
  7. DAlbertson

    Damping collision of low-mass actuator

    I have a 22 gram mass steel actuator hollow rod that slides on a rail. At the end-point of its travel, it collides with a solidly mounted steel plate. Just before the collision, the actuator rod is travelling at between 2.3 to 3.3 meters/sec, depending on other factors, so it posesses kinetic...
  8. DAlbertson

    Galvanic corrosion in new product

    Do dry film lubes last very long? I've used molybdenum disulfide based lubes in the shop, but I don't really have a good idea of their longevity. Are they easily scraped off by sliding action between two parts? Dave
  9. DAlbertson

    Galvanic corrosion in new product

    There are no lubricants in the device. There's only one moving assembly, and it's interface is 410 SS sliding on brass rod bearings. Velocities are small, as are forces. My customer asked for no lubes: the environment tends to be dusty and servicing these devices is problematic. Thanks...
  10. DAlbertson

    Galvanic corrosion in new product

    I'm sorry, I should have mentioned that the fastening used within the product was a combination of: 1) 302 Stainless screws, 2) Press fits (interference fits), 3) Cyanoacrylate adhesive on sliding fits Thank you! Dave
  11. DAlbertson

    Galvanic corrosion in new product

    I've started a small design company, and I have 3 corrosion questions on my first product. It is a mechanism about 1/2 the volume of a can of Coke. The parts are made of the following materials: 1) 260 Brass 2) 410 Stainless, powdered metal, 85% density 3) several different polymers 4)...
  12. DAlbertson

    Using a vacuum to improve varnish impregnation of a coil

    Terrific; thank you all very much! 1. I've looked at the Dolph's link, and will call them tomorrow for more information. 2. I'm checking ThomasNet for VPI equipment manufacturers, and should have those narrowed down pretty quickly because I believe our application is small relative to some...
  13. DAlbertson

    Using a vacuum to improve varnish impregnation of a coil

    ElectricPete, Thanks very much for the process description! I'm interested in a much smaller coil than you describe, about the size of the end joint of your little finger, but I don't see that the smaller size would greatly affect the overall idea. I've got a couple more questions, if that's...
  14. DAlbertson

    Scaling BH curves for non-fully-dense powdered metals

    MagMike, Thank you very much! I will use 0.85 as an approximation, multiplying only the magnetic flux density values, not the magnetic field strength values. (Sorry for the clumsy wording in my original post.) This is great! It's wonderful when something that seems like it ought to be true...
  15. DAlbertson

    Scaling BH curves for non-fully-dense powdered metals

    I'm designing several small parts in 410 or 416 stainless, to be manufactured in powdered metal. It is common to specify the density of a part to be 80% to 85% of theoretical (solid) density. Higher densities, essentially to 100%, are achievable, but all these are much higher cost: initial...
  16. DAlbertson

    Using a vacuum to improve varnish impregnation of a coil

    I need to improve the varnish impregnation of a coil wound onto a bobbin (Ticona Vectra C130) with 30 layers of AWG 40 single-build insulation, around a solid core 1.5 inches long and 0.4 inches in diameter. I'd like to have the varnishing process be scalable to a desktop-sized tank...
  17. DAlbertson

    Radially-oriented magnetization of Ring Magnets

    Wow, thanks! This is exactly the kind of information I need! If I may, let me direct comments and questions to each of you and then ask some general questions at the end. RHMagster - Thanks for the advice and pointers to the two PM shops. I'm writing an inquiry to them both, and will send it...
  18. DAlbertson

    Radially-oriented magnetization of Ring Magnets

    Engineers, I'm building a set of small (12mm stroke, 20mm diameter) linear actuators for an after-hours toy. This is only my 2nd magnetics project, so I need to ask for your tolerance. The DC actuators are based on Lorentz Forces with a small spring return. The coil is wrapped on a steel...
  19. DAlbertson

    Calculating the approximate inductance of a coil

    israelkk and Warpspeed, Thank you very much for your very helpful responses! Israelkk, you have found me out! [smile] I don't know a blessed thing about valve design, electropneumatic or otherwise, and the other 3 guys on the team know even less. Our (very small) company employs two...
  20. DAlbertson

    Calculating the approximate inductance of a coil

    Warpspeed, Thank you very much for your response. Regarding the PM return action, I agree with you completely: I think it is an unnecessary complication. The customer absolutely insists on it. A nice, (linear!) Hooke's law approach with an understressed spring seems to me to be far more...

Part and Inventory Search