Bevel-helical gear Reduction Boxes B4 eved using torquelimited backstops The standard B4-FH-18-D

Flender/Flender Gear Units/Bevel-helical gear Reduction Boxes B4

with 1-1% HCL solution about 1 minutes shall be carried out and surface must be thorought washed with water to remove acid & loose particles then dry completely before application of paint. 5.2 Procedure of Surface Preparation. 9 of 1 STANDARD TECHNICAL SPECIFICATION MECON LIMITED REGD. OFF: RANCHI 8 OIL & GAS SBU, DELHI DOCUMENT NO. Page 6 of 5 TITLE MEC//0/2/0 REVISION : 0 SHOP & FIELD PAINTING EDITION : 1 5.2.1 Blast Cleaning 5.2.1.1 Air Blast Cleaning The surface shall be blast cleaned using one of the abrasives: AL 2 particles chilled casts iron or malleable iron and steel at pressure of 7kg. Cm2 at appropriate distance and angle depending on nozzle size maintaining constant velocity and pressure. Chilled cast iron, malleable iron and steel shall be in the form of shot or grit of size not greater than 0.0 maximum in case of steel and malleable iron and 0.0 maximum in case of chilled iron. Compressed air shall be free form moisture and oil. The blasting nozzles should be venturei style with tungsten carbide or boron carbide as the material for liners. Nozzles orifice may vary from 3/1 to . On completion of blasting operation, the blasted surface shall be clean and free from any scale or rust and must show grey white metallic lusture. Primer or first coat of paint shall be applied within 4 hours of surface preparation. Blast cleaning shall bot be done outdoors in bad weather without adequate protection or when there is dew on the metal which is to be cleaned, surface profile shall be uniform to provide good key to the paint adhesion (..3to 5 ). If possible vacuum collector shall be installed for collecting the abrasive and recycling. 5.2.1.2 Water Blast cleaning Environmental, health and safety problems associated with abrassive blast cleaning limit the application of air blast cleaning in many installations. In such case water blast cleaning is resorted to. Water blast cleaning can be applied with or without abrassiv