Rotary Vane Pump

Using lessons from manufacturing and assembly to inform design adaptations

Project Summary

Tasked to fabricate precision parts for a rotary vane pump, I worked on skills in milling, turning, laser and waterjet cutting, sheet metal bending and sand casting. Oh, and measurement--over, and over, and over.

Expanding from this hands-on experience, my team was challenged to design a rotary vane pump for maple syrup. Given our practice in manufacturing and assembly, lessons from part quantity to convenience of deburring locations informed design decisions and reinforced DFMA considerations.

Skills
- precision
   machining
- material selection
- GD&T
- tolerance analysis

Timeline
Sep - Dec 2023
Fabrication:
15 weeks
Design Challenge:
7 weeks

Design Challenge
Collaborators
D. Chaykovsky
E. Daigle 
Z. Rodriguez

Pump Fabrication

Grateful for all the times I stopped and thought: let me measure this one more time, just to be sure. Thanks to many slow and steady nights in the machine shop, assembly day was smooth and stress-free. Instead of spending extra time adjusting parts, I got a moment to pause and celebrate the semester's end before returning to CAD Land (see below).

Design Challenge: Maple Syrup Pump

Design Constraints: 
Liquid: Maple syrup
Temperature: 40F - 100F
Inlet Pressure: 1ATM
Outlet Pressure: 5ATM
Speed: 1800rpm
MTBF: 5years using 100% duty cycle
(on 3 months, off 9 months)
Yearly Quantity: 20,000 units
Installation: a sugar shack in Vermont

Pump Design

Given the setting of a "sugar shack in Vermont," we considered how user operation in a non-industrial setting should inform our design decisions. 

The pump has sheet metal front and back guards to keep fingers clear of moving parts. Housing and pump stand along with rotor and shaft are single castings to minimize parts in contact with the syrup, as the user will be required to disassemble and thoroughly clean the pump seasonally. 

Material Selection

To determine appropriate grades of stainless steel for our uses, we looked to standards in the sugar processing industry. After collecting viable options for our parts, we compared material properties using Ansys Granta EduPack to whittle down our choices and assess functional requirements.

Resources from the International Stainless Steel Forum guided our material selection for pump parts. Using our inputs and known material properties, we verified our parts would withstand usage conditions by examining internal forces. 

Tolerance Analysis

Guided by D. Chaykovsky, our team completed a 32 stack tolerance analysis to validate nominal dimensions and margins of interfacing parts.

Drawings and GD&T

Produced drawings of all parts adhering to GD&T standards, strengthening practice identifying appropriate datum surfaces given functional requirements and critical interfaces.