OVERVIEW

Close-up of a white satellite dish covered in frost and snow, with a weather gauge and a person adjusting a cable in snowy, cloudy weather.
Technical drawing of a mechanical assembly with various colored parts, including a vertical gray rod, pink, yellow, and purple components, and multiple fasteners such as bolts and screws.
A 3D model of a mechanical component, possibly a gear or coupling part, with a cylindrical center and protruding rectangular arms.

Cad

Poppet

Check Valve in Action

Objective:

Create a one way valve that allows Cryo Lox to flow from the dewar to the tank with no backflow. (DESIGn a check Valve )

PARAMETERS:

  • Fit rocket envelope

  • be a fixed mounting point the qd system can reliably push against

  • have a mass flow rate around or better thAn COTS EQUIVALENT

Why not COTS:

The main issue with cots parts is their size. Cots parts are large both in length and DIAMETER. this is a challenge FOR us as we need the check valve to fit into the unique cavity bEtween the lox tank and the COMbustion chamber.

Iterations

SHOWN IN SEALING POSITION

v1

Cross-sectional diagram of a mechanical device featuring a central cylindrical component, a helical coil spring around it, and various color-coded parts including screws, nuts, and support structures.

  • self contained SPring sits within the chamber

  • PTFE sealing surface was secured with a TRIANGular steel ring

  • DESIGNED for an NPT thread

Take away:

i presented V1 at our OFFICIAL DESIGn review and it was approved by our in-industry alumni.later, I saw the unnecessary complexity in the COMPONENT and, through conversations with the end-CAp team, realized I could embed the spring in the end-cap. By doing this, I SIGNIFICANTLY reduced the size and complexity of the check valve, and I was now able to machine the top Body of the check valve in a way that made the steel securing ring in V1 OBSOLETE. A valuable lesson on desIGn iteration and PERSONAL RESPONSIBILITY.

v2

A technical cross-sectional diagram of a mechanical assembly showing various colored components including cylindrical metal parts, screws, and a central pink section with internal features, possibly representing a mechanical device or machine part.

  • Increased the inlet DIAMETER

  • Less COMPONENTS (easier and cheaper to produce)

  • reduced leak paths (o-ring groOves were adjusted)

  • More reLIable sealing surface

  • weaker Spring

  • spring sits on an overhang machined into the bottom end cap

  • Size was reduced

  • ‍DESIGNED for a ¼ in. COMPRESSION fitTing

Iterations

v1

  • The Poppet had Complete contact with the chamber walls

  • holes DRILLED thRough to allow flow past the poppet

Testing

v2

Close-up of a metallic valve with a white handle on a wooden surface.

  • Three PRONGED design to MAXIMIZE flow past the poppet

  • DESIGn was observed wobbling in the chamber

A large metallic cylindrical vacuum tube with multiple fittings and cables, resting on the tiled floor of a laboratory or workshop, supported by black foam blocks.

HYDROSTATIC testing: filled tank with water and PRESSURIZED to 700 psi and monitored for 5 min. Check valve did not leak, the tank also did not leak.

v3

A 3D model of a mechanical component with six evenly spaced protrusions, resembling a gear or coupling part.
A computer-aided design (CAD) model of a pink, block-like structure with curved bottom edges and a flat top surface, viewed from the front.

  • Increased the negative space

  • increased points of contact on the wall, preventing the poppet from becoming MISALIGNed

  • Added knife edge

Close-up of a weather station with frost, showing a pole and instrument with snow-covered ground and cloudy sky in the background.

COld Flow: CHeck valve had a drip leak in the first cold flow, bolts were found to be loose. For all fOllowing tests, the chEck valve did not leak and pERformed as expeCted.

IMAGES

A wooden work surface with metal mechanical components, screws, washers, a blue cloth, and some signage painted on the wood.
Close-up of a metallic machinery part with multiple screws and a central hollow cylindrical opening, mounted on a black base with a yellow stripe.
A person is holding a small metal machined part with a cylindrical shape and a protruding rod, in front of a computer keyboard and desk surface with paint marks and scattered paint splashes.
Close-up of metallic mechanical components, possibly part of a machine or engine, with some oil or lubricant visible.