Mech
Machine Design
Area of practice · Donald W. Parnell, PE · Mechanical Engineering Technology
Machine design education, CNC and tool-and-die machining, semiconductor process-equipment setup, automated production-line design, textile plant layout, filtration equipment, and electromechanical switchgear and high-voltage apparatus.
Education
Mechanical engineering technology
Mr. Parnell’s degree in Mechanical Engineering Technology from Texas State Technical College, Waco, an ABET-accredited program, was built around machine design: mechanisms, drives, strength of materials, machine elements, and the detailing of parts and assemblies. His electives were in CNC machining and robotics. That foundation runs under the machining, equipment, and production-line work that follows.
Machining
CNC operation and high-tolerance tool-and-die work
Mr. Parnell worked as a CNC operator on Bridgeport Series I and Series II vertical milling machines, developing short-run parts for the semiconductor industry — small lots of precision components, programmed and set up per job rather than run in volume. At Turnco Tool and Die he performed high-tolerance machining for Eaton Corporation, holding the close dimensional and surface requirements that tool-and-die work and semiconductor-equipment components demand.
Semiconductor Equipment
Ion-implantation assembly process and fab setup
At Eaton Corporation’s semiconductor-equipment operation, Mr. Parnell set up assembly-line processes for ion-implantation devices, the machines that implant dopant ions into silicon wafers. Setting up the assembly process meant defining the sequence, stations, fixturing, and checks by which the implanter subassemblies were built and integrated. He was also involved in equipment setup at the Advanced Micro Devices plant in Austin, Texas, installing and commissioning the equipment at the customer’s fabrication facility.
Production Lines
Automated refrigerated production-line design
For Wight Engineering in Austin, Mr. Parnell worked on the Glacier 2000 automated ice-cream production lines described under HVAC. Beyond the refrigeration, the project involved a great deal of machine design: the conveyors, stations, and mechanisms that moved, formed, filled, and packaged product continuously through the refrigerated line, with the drives, guarding, and frames those mechanisms require.
Textile Manufacturing
Plant layout for textile machinery
At Burlington Industries in Greensboro, North Carolina, Mr. Parnell performed plant layout for textile equipment, including automatic looms. Plant layout for weaving and finishing machinery sets the machine arrangement on the floor for material flow, operator access, and maintenance clearance, and locates the power, air, and utility connections each machine needs.
Technical Engineering
Drafting and parts-parameter indexing
In the technical engineering department at IBM in Research Triangle Park, Mr. Parnell performed mechanical drafting and ran the parts-parameter indexing system, the system by which part dimensions, tolerances, materials, and identifiers were indexed so that parts could be located and reused across designs. This was alongside the manual drafting and CADAM exposure recorded under CAD Background.
Filtration Equipment
Biological-fluid filtration systems
Mr. Parnell worked for NCSRT in the Research Triangle area, a designer and manufacturer of filtration and separation equipment, on blood-filtration equipment. NCSRT’s systems are tangential-flow and ultrafiltration units used to separate components of biological fluids for pharmaceutical and diagnostic production; the equipment combines the filter modules with the pumps, housings, manifolds, and frames of a process machine.
Electromechanical
Switchgear and high-voltage apparatus
At Square D, Mr. Parnell worked on switchgear design, which is electromechanical: the operating mechanisms, interlocks, racking, and enclosures of the gear are machine design in service of an electrical function. The same is true of much legacy high-voltage equipment he worked with in substation design. Air-break switches are mechanisms — linkages, operators, and contacts driven through an operating rod — and autotransformers and oil circuit breakers are heavy mechanical assemblies with tanks, bushings, radiators, and operating mechanisms as much as they are electrical devices. Most such equipment is a mixture of electrical and mechanical operation, and its layout, support, and maintenance access were mechanical design problems within the electrical work.
About this record. This site is a working record of professional experience, maintained to verify subject-matter background. Areas of practice are reached from the menu above. The record is expanded as additional work history is documented.
Donald W. Parnell, PE | North Carolina PE No. 33878