1、 FORD LABORATORY TEST METHOD BA 012-01 Date Action Revisions 2001 01 30 Revised Editorial no technical change A. P. Cockman 1990 03 31 Printed copies are uncontrolled Page 1 of 2 Copyright 2001, Ford Global Technologies, Inc. ROPING RATING OF STAINLESS STEEL Application This method covers the determ
2、ination of the ductility as interpreted by the roping (riding) number. This is a visual interpretation performed by comparing the mill finished coil or sheet stainless steel stock sample with a master set of standards. (Roping is a defect consisting of surface corrugations or ridges that result from
3、 a stretching operation. The ridges are in the direction of final cold rolling of the material regardless of the direction in which the material is stretched.) Equipment Required Tensile Machine Capacity - 2500 N Rate of loading - 10 mm/minute at a constant strain rate. Any equipment which will pull
4、 specimens to a 15 % elongation under above conditions. Center Punch A punch with 76 mm centers for marking tes specimens. Elongation Scale 1 set of Rope Standards, No. 1 - No. 6. The Product Quality Office, World Headquarters, has a master set of standards. Materials Required Trichloroethane (M5B58
5、) or equivalent. Caution: TLV - 350 ppm - Refer to Industrial Hygiene Bulletin No. 14. Preparation of Samples Select samples from coil stock in the following size: Width - 25 mm to 57 mm. Any width in this range may be used, depending upon the slit width of coil. Length - 150 mm Thickness - Stock th
6、ickness. FORD LABORATORY TEST METHOD BA 012-01 Page 2 of 2 Copyright 2001, Ford Global Technologies, Inc. Any sample which requires work to bring the width dimension to within 25 mm to 57 mm must be sheared or slit to the size. Preferably it should be milled to finish dimensions. Surface finish shou
7、ld remain as received. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified
8、. Procedure 1. Using punch, stamp 76 mm gage length centrally located on the sample. 2. Clean sample with solvent or by degreasing to remove surface dirt and imprints. A clean surface will eliminate misinterpretation of the roping rating. 3. Load samples in holders of tensile machine using 25 mm gri
9、p on each end. 4. Set elongation scale for 15 % elongation. For 76 mm gage length, use 88 mm. 5. Start machine and pull specimen at a rate of 10 mm/minute until travel of machine matches setting of elongation scale. 6. Remove specimen and compare sample with the master sets of rope rating. 7. Report results of rope rating by number. Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities.
