Technical Brief Air Gaging George Schuetz 2017 Air

Technical Brief Air Gaging George Schuetz 2017

Air Gaging from Mahr Federal • Objectives – To understand why air gaging is a valuable Dimensional Measurement Solution – To learn about the Air Gaging products available – To learn some of the applications for Air Gaging – To learn some of the changes implemented at Mahr Federal to improve product line Mahr Federal 2 - Technical Brief 2017

Why Air Gaging? • Air Gaging is a measuring system that – Allows for fast measurement • Self aligning – Provides high resolution • Performance to 0. 1 um/5 u” – Easy to use • Little operator skill involved – Is non-contact • Won’t mar the part – Self-Cleaning • Air blows away surface contamination Mahr Federal 3 - Technical Brief 2017

When to use Air Gaging? • Have a tight Tolerance condition – <± 40 um / ± 0. 0015” • Know when a part is good or bad – Know the variation from the nominal • Have a high volume of parts to measure – Measure quickly with min. operator influence • Or, have a geometric measurement – – maybe not of high volume but where alternative measurements (i. e. CMM’s) are too time consuming • Taper. Straightness/Center Distance • Environment is dirty Mahr Federal 4 - Technical Brief 2017

Is Air Gaging Difficult to Apply? • No – applying air gaging is often no different than selecting an adjustable bore gage, fixed mechanical plug gage, or a snap gage • You need to know the same information – – Size Tolerance Where the measurement is to be made What is the surface finish* • But watch out! Mahr Federal 5 - Technical Brief 2017

Principles of Air Gaging Just like a garden hose – as the distance D gets smaller and restricts the water flow – pressure builds up in the hose. What can you say about the flow of the water as the distance is changed? D Water and air act very similar! P Mahr Federal 6 - Technical Brief 2017

What’s Happening with Flow and Pressure + + Flow Pressure 0 Distance + Flow increases as the distance between the nozzle and restriction increases Mahr Federal 7 - Technical Brief 2017 0 Distance + Pressure increases as the distance between the nozzle and restriction decreases

Types of Air Gage Systems • Fixed Magnification – Single Master – – Lower master costs Faster to set up Accuracy built into gage Can use Master Restrictors to qualify system – Dirt and oil in air system can change calibration – Must match display and tooling Mahr Federal 8 - Technical Brief 2017 • Adjustable Magnification – Two Masters – More master cost – Harder to set up – One amplifier can work with a variety of tooling – Can verify its own calibration – Can compensate for worn tooling or dirty system

The type of air gage selected – determines where the error may be Single Master System Errors at extremes of tolerance Mahr Federal 9 - Technical Brief 2017 Dual Master System Errors at center of tolerance

Dimensionair Fixed Magnification System Easiest to use True Analog Display Single or Multiple display units – taper and diameter Mahr Federal 10 - Technical Brief 2017 Universal Dimensionair Adjustable – two master system Compatible with most competitive tooling

Column Gages 1840 Column 1841 Signal Sharing Column -Single air input -Up to 4 air inputs -Single / Dual Mastering -Full feature column – dynamics, outputs, classification, multi- color LCD -Full feature column – signal sharing for math equations, dynamics, outputs, classification, multi-color LCD Mahr Federal 11 - Technical Brief 2017

u. Dimensionair • Portable or bench mounted air gage display • Adds portability to air gaging • Interchangeable parts make it configurable for many applications • Uses standard Mahr Federal single master tooling • Magnifications 60, 50, 20 • Operates like a u. Maxum Mahr Federal 12 - Technical Brief 2017

Bench Amplifiers for Air 832 C 1208 C 1245 Fixed Magnification Full feature amp Single or dual input Full feature amp Single or Dual mastering Single or dual mastering Single input Up to three separate display readings Single or Dual input PC programmable Full feature with analog meter Mahr Federal 13 - Technical Brief 2017

What makes up an Air Plug? • Hardened Steel cylinder with air passages and opposed jets • Air passes through the probe then through the jets • Proximity of part to jet throttles air flow resulting in pressure changes • An air gage instrument measures pressure and displays part size Mahr Federal 14 - Technical Brief 2017

Why is Surface Finish Important? What is the true size? Mahr Federal 15 - Technical Brief 2017

Types of Plugs • Body Styles – Jet locations – – Thru hole – 12. 5 mm/0. 5” Blind – 4 mm/0. 156” Super Blind 2. 4 mm/0. 094” Relieved/Non-relieved • Continuous body length – Stop Collars • Specific depth or short land Mahr Federal 16 - Technical Brief 2017

Types of Plugs • Two Jet – Most common for ID/OD, check form errors – diameter variation, bell mouth, taper, barrel shape Mahr Federal 17 - Technical Brief 2017

Types of Plugs • Three Jet – For checking diameter variation on parts with triangular form error – Used with standard 2 -jet system • Four Jet * – For average diameter reading – requires four jet Dimensionair • Six Jet * – Average readings of three diameters – tends to find average diameter of two or three point out of round conditions *Requires proper Air Display System Mahr Federal 18 - Technical Brief 2017

Measuring OD’s • Air Rings are available in 2 or 3 jet configurations • Snaps are available in single or multiple circuit configurations Mahr Federal 19 - Technical Brief 2017

Air Gaging Applications • No other method can get so many measuring points in a such a small area Mahr Federal 20 - Technical Brief 2017

Process Improvements @ Mahr Federal New Material for Standard Plugs • Create two standard plug options – HCC (High Chrome Content Stainless Steel) – Chromed HCC • Benefits of the HCC line – Reduces manufacturing steps – shorter delivery – Reductions can be passed on to the customer – lower price – Harder Material • Previous 45 – 48 Rockwell • HCC is 68 Rockwell – Same life and appearance • Subjected new material to 500 K lifecycle and salt bath test • Same performance as Chromed plug • Lower pricing and faster delivery! Mahr Federal 21 - Technical Brief 2017