jonai Committee, EDC 27 (Second Reprint JULY 1988) UDC earesea] toe: [e9e4] :681°7968e 000-87 1S : 1367 ( Part X11) - 1981 —_——————— dndian Standard (nerd TECHNICAL SUPPLY CONDITIONS FOR... THREADED STEEL FASTENERS PART Xil PHOSPHATE COATINGS ON THREADED FASTENERS { Second Revision } 4. Scope —Covers threaded steel fasteners with coating consisting-of zinc phosphate that is Intended to be used In conjunction with a sealant for protection against corrosion. 2, Phosphate coating shall be s Jed with suitable oll of rust-preventive type, EDC #7 (2978)) 3, Mass of Phosphate Coating— The mass of coating that consists of zinc phosphate shall have a'coating weight of 2°5 g/m® to 4°S g/m of treated surtace. 4, Designation — The designation of @ bolt or screw with phosphate coating shall include the Z| letter ‘P' for phosphating. {see also IS : 1367 ( Part XV1)-1979 Technical supply conditions for =| threaded steel fasteners : Part XVI Designation system and symbols (second revision). et Doe: Example: ‘A hexagon-head bolt conforming to, for example, IS : 1364, of size M 20, length 75 mm, product grade A, property class 8.8 and with phosphate coating shall be designated as : HEX BOLT M 20 x 75 1S 1964-A-8.6-P. | 5. inspection, Sampling and Testing 4] 5.1 Freedom from Defects —‘The surtace of phosphate coated fasteners shall be matt without any i aceaaivly rystllie appearance. ‘They shall be free from untreated patches and trom flaky and uneven deposits. £1 8.2 Verification of Costing — A chemical method for verifying the presence of a phosphate coating Is glven in Appendix A. 4.3 Dimensional Accuracy 5.3.1 In case of unthreaded features, dimensions apply before coating. 5.3.2 For threaded features, the permissible dimensional variations will be applicable before coating. However, after coating, the thre all not transgress the maximum material limit for tolerance position H or h. If required by the purchaser, fasteners may be checked at random for dimensions after de-phosphating. Botte, Nute and Fastone 5.6 Test for Mass of Coating — Test for mass of coating shall be in accordance with | “Phosphate treatment of iron and steel for protection against corrosion * 18-1968, 5.5 Test for Resistance to Corrosion — The resistance of seated fasteners to corrosion shall be tested In the laboratory by means of Salt Spray Test as described in Appendix B, The tested 8 shall be practically rust free after the stipulated duration. ‘Adopted 28 December 18et BUREAU OF INDIAN STANDARDS ANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELMI 1100021S: 1367 ( Part XIl)= 1981 APPENDIX A (Clause 5.2) CHEMICAL TEST FOR THE PRESENCE OF A PHOSPHATE COATING ‘At, Reagent — Dissolve 8 9 of ammonium molybdate In 80 mi of distilled water. Add 12 ml con- ‘cenirated hydrochloric acid (d = 1"14), 20g ammonium chloride and 10 ml of saturated potassium persulphate solution. The reagent shall be freshly prepared. ‘A-2. Procedure — Add one drop of the reagent to the test surface. The appearance of a blue ‘colour within 30 s indicates the presence of a phosphate coating. Aplain untreated fastenor shall be used as control, APPENDIX B (Clause 6.5) SALT SPRAY TEST B-1, Test Equipment B-1.1 Tho equipment required for Salt Spray Test consists of a fog chamber, a salt solution reser~ voir, a supply of sultably conditioned compressed air, one or more atomizing nozzles, specimen supports, provision for heating the chamber, and necessary means of control. ize and detailed construction of the equipment are optional, provided the conditions I be insulated to avold temperat temperature control. B-1.2 Drops of solution which accumulate on the ceiling or cover of the chamber shall not be permitted to fall on the specimens being tested. B-1.3 Drops of solution which fall from the specimen a! for re-spraying. B-1.4 The spray from the atomizing nozzle or nozzles shall be prevented from impinging directly ‘on the test specimen by means of sultable baffles. The solution condensing on the baffies may be Feturned to the salt solution reservoir; this can effect 2 substantial economy In rate consumption of the solution. Adjustable baffles are of assistance in obtaining a uniform collection rate through- out the test zone of the chamber. B-1.5 Materials of construction shall be euch that they will not affect the corrosiveness of fo9 (glass, rubber or certain plastic materi ultable ). B-1.6 The equipment shall be sited eo as to be In diffused light and away from radiators or other ‘sources of heat and draughts In order to facilitate temperature control. B.2. Test Samples B-2.1 The number of test to be used, as well as the criteria for the evaluation of the per test results, shall be defined in the epecifications of the product being tested or shall bo mutually agreed upon by the purchaser and the supplie B.2.2 Select samples of the fasteners which are free from accidental damage and dirt. B-3, Position of Specimens during Test B.3.1 The specimens shall be suspended by cotton, nylon or any suitable thread vertically. Unless otherwise specified. the specimens shall be supported between, 15° to, 90° from the yeitcal and preferably parallel f0 the principal direction of horizontal flow of fog through the chamber. Tho test specimens shal! be atleast 90 mm from any other specimen ‘and 38 mm from any wall of the amber. B-2.2 The specimons shall not contact each other or any metallic material, B-3.3 Each specimen shall be #0 placed as to permit free settling of fog on all specimens. B.3.4 The salt solution from one specimen shall not be allowed to drip on to any other specimen, 2 1 not be returned to the solution reservoir1S: 1967 ( Part XI1)- 1988 8.4, Test Solution B-4.1 Preparation of Solution — Dissolve 80 -L5 9 sodium chloride in each litre of distilled or de- ionized water or water containing less than 100 ppm of total dissoived solide and substantially free trom dissolved heavy metals particularly nickel, copper and iron. ‘The pH of the solution shall be auch that, when atomized under the test condition, the collected solution will be In the pH range of to 72. B-5. Air Supply B-5.1 The compressed alr supply to the nozzle or nozzles for atomizing the salt solution shall be {ree from oil, oi! vapour and dirt, and shall be maintained between 0°67 bar and 172 bar (1 bar = 1 kg/em? ). B-5.2 Tho air shall be saturated with moisture by means of water wash or humidifying tower, after suitable filtration. It Is preferable to operate the tower at temperature wall above the chamber temperature to ensure wot fog to offset heat losses required tom chamber. The tower temperature should be ad} sition of collected fog are kept within the specified limits, For guidance lower temp at different air pressures required to offset the cooling effect of expansion at the nozzle or nozzles to atmospheric pressure with a chamber temperature of 35°C. or nozzles may be operated intermittently by means of a actuating a solenoid valve in the air supply, ing that the f provides means of adjusting the collection rate and It also ensure bution with minimal directional effects. B-6, Test Conditions B-8.1 Temperature — The exposure zone of the test chamber shall be maintained at 352°C. B.6.2 Alomization and Quality of Fog — At least two clean fog collectors shall be placed in tho ‘exposure zone in the proximity of the test specimens, one near to a nozzle and another as far as possible from nozzle. They shall be positioned so’ that no test solution falling from the test Speciman Is collected. The fog shall be such that for each 8 000 mm* of horizontal collecting area there will be collected in each collector from 1 to 2 ml of solution per hour determined over an operating period of at least 16 hours. ( Standard laboratory glass funnels or dishes with 100 mm dig have horizontal area of 8000 mm * ). The collected apray solution shall contain 50 :t 10 gil of sodium chloride ( specific gravity 10256 to 1°0400 at 25°C) and pH shall be 65 to 72. 7, Continuity of Test B-7.1 Unless otherwise specified in the specifications of the product being tested, the test shall be continuous fort he duration of the entite test period. Continuous operation ‘implies that the chamber be closed and the spray operating continuously except for the short daily interruptions. necessary to Inspect, rearrange, or remove test specimens, to check and replenish the solution In the reservoir, and to make necessary recordings, Operations shall be so scheduled that these Interruptions are kept at a minimum. B-8, Period of Test B-8.1 Tho poriod of test shall be 48 hours. 8-0, Procedure B-9,1 The following procedure shall be carried out : 1) Expose the epecimen In the cabinet for the specified period, 2) Remove the specimen, wash in cold running water and dry off. B-8.2 There shall be no rust formation on Immediate visual examination. 14 continuously. T! ‘a more consistant fog distri 318: 1367 (Part Xi) ~ 1981 EXPLANATORY NOTE Consequent to the decision to revise 1S 1367-1987, aplitting it into separate parts, this: standard on requirements for phoaphating of fasteners has been formulated, Although IS :3618- 1988‘ Phosphate treatment of Iron and steel for protection against corrosion’ covers the general Faquirements for phosphating, a need was felt for special requirements of tastenera. In the preparation of this standard, assistance has been taken from BS : 3189-1973 ‘Phosphate treatment of iron and steol,' Issued by the British Standards Institution.