Pipe Shoe Technical Guide for North America Vol. 1 July 2022 | Page 11

Modular Pipe Shoes Technical Supplement
1.0 INTRODUCTION 1.7 CORROSION
The following is an overview of typical finishes used on Hilti Pipe shoe products . For more detailed information from Hilti on material finishes and corrosion protection , please consult the Hilti Corrosion Handbook which can be found under the relevant section for Pipe shoe portfolio items on Hilti Online .
CORROSION HANDBOOK
12 / 2021
Hot Dipped Galvanized ( HDG )
Component parts such as base plates and system connectors have zinc coatings applied by the hot-dipped galvanizing ( HDG ) process in accordance with the ASTM A153M Standard . On hot dipped galvanized parts , the zinc coating process occurs after cold forming and punching . The parts are pretreated , pickled , and then dipped into tanks of molten zinc . HDG provides increased corrosion resistance compared to PG and EG finishes . HDG conforms to ASTM A153 / A153M galvanizing as stated on the product sheet for beams , connectors , bases , splices , and fasteners . Suitability of a HDG finish for a product must be assessed for each project .
Zinc Magnesium ( ZM )
Outdoor Coating ( OC )
The Hilti MT-PS System for outdoor applications has been developed with various corrosion protection technologies and consists of two finishes : Hot-Dipped Galvanized ( HDG ) and Zinc Magnesium ( ZM ). The Hilti OC is intended primarily for use in environments considered Outdoor with low pollution . For more corrosive environments , additional protection may be required . The proper amount of corrosion protection for a given application should always be assessed by the Design professional to ensure products meet the project requirements .
MT profiles such as strut , channels , and girders are coated with zinc-aluminum-magnesium alloy ( ZM ) by a continuous hot-dip galvanizing process during the steel coil phase in accordance with the EN 10346 Standard . On Zinc Magnesium parts , the process involves sheet metal coils that are drawn continuously through a bath of molten zinc after the surface has been cleaned and it is subjected to a special annealing process . In addition to zinc , the molten bath contains Magnesium ( Mg ) and Aluminum ( Al ). The Aluminum reacts with the steel surface to create a layer with a thickness of 0.984 mils per side ( 1.02 ounces per square foot ), which inhibits the formation of ZnFe phases . Hilti ’ s OC ZM processing conforms to the EN 10346 Galvanizing Standard .
1.8 ABBREVIATIONS
The following abbreviations are used throughout this product technical guide :
• NPS = Nominal Pipe Size
• D = Outer Pipe Diameter
• ASD = Allowable Strength Design
• LRFD = Load Resistance Factored Design
• LSD = Limit State Design
• H Base
= Distance from bottom of support to bottom of pipe clamp
• H Center
= Distance from bottom of support to centerline of pipe axis
• H Max = Distance from bottom of support to top of upper pipe clamp
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