aruna
aruna

Design & Development

The Design lab at Aruna Alloys boasts of the best in breed people, process and technology to ensure minimal error and rework. The product development and design department drafts and designs using CAD/CAM before development. Equipped with Magma for solidification analysis, all simulations adjustments and allowances are made at design unit.

Melting & Moulding Facilities

All the 3 plants operate on Medium Frequency Induction Melting Furnaces. Furnaces ranging from 250 kg, 1 MT, 2MT and 6MT have been installed across the 3 production facilities. Aruna has strategically positioned the 3 units to cater the wide range of casting weights for the body and components of valve manufacturers to provide a one-stop shop for sourcing. As rate of pouring and furnace temperature loss after tapping of metal are critical to maintain quality, a wide array of furnaces are operated. Depending on the liquid metal requirement, the plant for pouring is chosen by the product development team. Currently, we can pour a 6 Ton casting by running the 6MT furnace Dual Track to tap 12 MT of liquid metal.

 

The moulding process across the 3 plants is hand moulding Co2-Silicate process. Airset cores are taken on special cases depending on criticality of the casting. Intensive process control is being put in place to ensure consistency in the manufacturing process.

Bottom Pouring

All medium & large size castings weighing from 250 Kgs upto 6500 Kgs are poured using Bottom Pouring Ladles. There are 15 Ladles in all the 3 units ranging from 250 Kgs to 12,000 Kgs Liquid metal Capacity. The adequate capacity and flexibility in transporting Liquid metal to the mold helps in planning to tap only sufficient quantity of metal required for pouring. As pouring weight varies based on casting size and pressure class, a consistent rate of pouring is maintained by using the appropriate Ladle to manufacture a clean casting. To pour Duplex and Gaseous type of materials, Argon Purging facilities in the Ladle are provided to inject Argon Gas into the bottom of ladle. The bottom pour ladles enhance the metal quality, improves the head pressure, and provides a consistent flow rate with minimal air entrapment due to operator variation. Small Castings ranging from 5 Kg - 250 Kg in weight are poured using Tea Spout Ladle to reduce the rate of pouring to avoid erosion of the mould.

Test Lab

The testing units in aruna has the following departments, Physical Testing (including Universal Testing Machine, Hardness Testing , Impact Testing Machine, Metallurgical Microscope with Photographic Attachment), Chemical Testing (Optical Emission Spectrometer: capable of checking 30 elements), Wet Analysis, Radiographic testing etc.

Sand test lab

Sand is the basic ingredient that helps build the casting quality by reducing inclusions and gas entrapment during metal pouring and solidification. Effective controls with a strong sand testing lab have been setup in every foundry facility to test incoming sand and process sand. Incoming sand is tested for AFS, Clay Content and Loss of Ignition (LOI), and only accepted material is used for production. In process sand, Permeability, Moisture and Compression Strength are tested for every batch to ensure consistency in mould making.

Wetlab

The incoming material such as alloys and scraps with irregular metal surfaces are checked for its chemical composition by wet analysis.

Spectro unit

Optical Emission Spectrometer . This equipment can check 30 elements including Nitrogen, Oxygen and Boron in four bases namely Iron Nickel, Cobalt and Copper.

Final Inspection

The prepared castings are checked for visual, dimensional and invisible defects. Magnetic particle and dye penetrant tests are also conducted at this station. Weld repairs are carried out for discovered defects.

Dimension Inspection

All sample castings and random bulk production castings are inspected for dimension consistency. Wall thickness report is provided to the customer as required for bulk production castings. Dimensional variations are immediately updated to the patternshop and process control to make necessary corrective actions. Dimensional inspection area plays an integral part of casting development for maintaining accuracy in the product supplied to minimize rework during machining. In order to support the technical development team, young engineering graduates coordinate the functions in this area.

Magnetic Particle Testing

Magnetic Particle Testing is 100% performed on Carbon Steel Castings and Low Alloy Steel Castings to identify cracks, surface discontinuities and sand entrapment in the surface. Dry, Wet and Flourescent Method are practiced at Aruna. Magnetic Particle Testing is done as per customer specification in accesible Areas. If no special mention is given in the Customer Spec, then Dry method is practiced. Both Yoke and Prod method are available for testing.

Pickling & Passivation Facilities

For all Stainless Steel and Duplex Steel Castings Pickling and Passivation is done to clean the impurities in the surface. Every unit is setup with own material handling facilities and buzzer systems to control the pickling and passivation of castings. Material Handling facilities are provided for each tank to hold the casting during the cleaning process.

Penetrant Testing

Penetrant Testing is 100% performed on Stainless Steel, Duplex, Super Duplex and Nickel Alloy castings. As these materials are non-magnetic, Penetrant Testing is done to identify Cracks and surface defects. Water Washable and Solvent Removable methods are practiced at Aruna in all the 3 facilities. Penetrant Testing is done as per customer specification in accesible areas. As a standard, Water Washable Technique is practiced in Aruna. Solvent Removable is done if requested in the Customer's inspection requirements.

Heat Treatment & Fettling

1. Heat Treatment

 

Sufficient capacity in Heat Treatment process has been invested to handle the various customer requirements. A total of 9 Heat Treatment Furnaces in all the 3 Units have been setup. All the Furnaces are calibrated by 3rd Party according to procedure API 6A (Appendix H). 5 Electric Furnaces ranging from 1 MT to 3 MT capacity and 4 Oil Fired Furnaces ranging from 3 MT to 20 MT have been installed. The Furnaces have been designed to reach high temperatures of upto 1250 Degree Centigrade required for the High Alloy Steel and Nickel Alloy Steel Grades. 2 Electric Furnaces with Automatic Quenching facilities have been also installed to maintain process consistency.

 

2. Shot Blasting Machine

 

7 Hook-Hanger type shotblasting machines have been installed at the 1st Stage Fettling and Final Finishing Fettling areas of each plant. Shot blasting capacity ranging from 500 Kg to 12 MT have been installed to suit each plant's surface quality requirements. With the diverse range in capacity focussed on the casting weight and size at each plant, Aruna has been able to satisfy customers with excellent surface finish quality.

 

3. Grinding & Welding

 

Electrically operated high speed grinders are used for final finishing of the castings. Welders are qualified for each grade as per ASME Section IX and EN Standards to support the upgradation of castings. Careful material handling of welding electrodes is done to ensure quality of welding.

Despatch & Packing

Finished products are sorted, tagged, packed and loaded for transportation in this area. For export customers, un-machined castings are packed into Wooden Crates or Wooden Boxes depending on the customer's preference. For very large and heavy castings, wooden pallets are used. Machined castings are given protective covering in the machining surface to avoid damage during transit. Protective Anit-Rust coatings are given for Carbon Steel & Alloy Steel castings to avoid rust formation during sea shipment.

 

Castings can be both transported to Sea ports which are 3 hours away and also be given for Air Shipment at Chennai. With significant volumes leaving Indian ports, Aruna has established long term relationships with Carrying and Forwarding Agents to handle the port activities to clear shipments efficiently.