Performance Fluids UCON Quenchants. UCON Quenchant. The Dow Chemical Company. Page 1

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1 UCON Quenchant The Dow Chemical Company Page 1

2 Introduction Background Cooling mechanism Types of quenchants PAG quenchants UCON Quenching Fluids History Products available Steel, aluminum quenching Quench bath maintenance Trials at Dana Toluca Page 2

3 Background Page 3

4 What is Heat Treating? Heat Treatment is an operation involving heating to an elevated temperature, followed by controlled cooling to enhance properties such as hardness, toughness, and corrosion resistance. What is a Quenchant? The primary function of a quenchant is to control the heat transfer rates from parts during the quenching process, thus producing the desired hardness, strength, and toughness. Simultaneously, the quenchant should minimize distortion and residual stresses. Handbook of Quenchants and Quenching Technology Page 4

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6 Quenching Mechanisms The quenchant must mediate heat transfer Vaporizable liquid exhibits three stages of cooling 1. A Stage (Vapor Stage) slow 2. B-Stage (Nucleate Boiling) rapid 3. C Stage (Convective/Conductive) slow Uniformity of cooling controls stress/distortion Stable vapor blanket critical for uniformity Page 6

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10 What Materials Can Be Used As A Quenchant? Commonly used quenchants Oil Gas Water Aqueous polymer systems Also used as quenchants Brine Molten salts Fluidized beds Others Page 10

11 Quenchants, cont. Most common aqueous polymer quenchants Polyalkylene glycol (PAG) Polyvinyl pyrrolidone (PVP) Polysodium acrylate (PSA) Polyethyloxazaline (PEOX) Today we will discuss PAG Quenchants PAG Quenchants comprise 80% of ALL Polymer Quenchants used in N. Am. Page 11

12 PAG Quenchants Page 12

13 Advantages of PAG Quenchants vs. Other Polymer Quenchants More stable solutions Shear stable, Hydrolytically stable Less sensitive to hard water and iron oxide scale Easily removed from workpiece Excellent quench uniformity uniform physical properties Biodegradable Quenchant bath clean-up by thermal separation Less quenchant intensity variation with ageing baths Factory Mutual approval Page 13

14 PAG Quenchants Factory Mutual Approval FM Approvals, Inc. ( Factory Mutual ) is a company that determines and rates the flammability characteristics of materials Rating scale = 0-2 [0 = will not burn under test conditions] Rating 0-1 FM Approved Rating 2 Specification Tested Lower ratings can often be used to reduce insurance premiums All UCON Quenchants are rated 0 Oil quenchants are unrated Only UCON Quenchants have entire product portfolio rated 0 by Factory Mutual Page 14

15 Advantages of PAG Quenchants vs. Oil Fire hazard and smoke eliminated Environmental safety spills easily cleaned up Lower quenchant costs Flexibility multiple quenching speeds from same product Reduced processing costs insurance costs lower Easier maintenance and housekeeping Improved performance Page 15

16 Quench Oil Fire at MT Heat Treating Page 16

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19 Advantages of PAG Quenchants vs. Water Water exhibits non-uniform heat transfer due to vapor blanket instability Non-uniform heat transfer creates thermal gradients which cause high residual stress and distortion PAG quenchants stabilize vapor blanket cooling to facilitate uniform heat transfer Result Quench cracking and distortion reduced or eliminated Page 19

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