Sigma Electric Manufacturing Corporation

Viren Joshi, CEO & President, Sigma Electric Mfg. Corp.

Technological Advancement:

Technological advancement promotes operational excellence, by allowing manufacturers to develop new products that can be cost competitive in comparison with conventional processes. They also permit manufacturers to produce high-quality products as per customer’s specifications. These processes are good for the environment because they often consume fewer raw materials and generate less scrap. They improve safety as well, by exposing workers to fewer hazardous materials.

At Sigma, we believe that the technological advancement will have the greatest potential to influence the manufacturing landscape and will enhance productivity in the coming years.

Sigma has developed a proprietary state-of-the-art Special Purpose Machine (SPM) design and development technology centre. Highly engineered production equipment’s with significant engineering capabilities are manufactured with highly customized machinery and extensive robotics utilization which boosts overall productivity & quality performance and reduces cost.

The technology centre is equipped with modern design facility and software’s with experienced design team having sound knowledge on design in mechanical assembles, hydraulics, pneumatics, mechatronics, electrical systems, robotics and automation. The centre is also equipped with inhouse PLC programming facility, assembly shop tool room, test equipment’s, IOT laboratory and Cobot simulation centre to explore various trials and process design which helps for speedy execution.

The process steps for Special Purpose Machine (SPM) building are: concept design, design review, manufacturing of parts, assembly of machines, control panel wiring and installation, hydraulic piping and power pack installation, and trial & commissioning.

Concept Design:

Inputs required for SPM design such as product volume, product process flow, product drawing, etc. are captured in this stage. Cost centre number is generated for identification of machine. Depending upon the complexity of the machine, plan is designed. Concept is designed on the basis of inputs given by the customer. In basic, concept design feasibility check is done by cross functional team. If similar type of machine is available in plant, Things Got Wrong (TGW) & Things Got Right (TGR) are referred to avoid repetition of work. SPM design is done with Solid works 2018 SP0.1 software. In design, standard parts are for the machine completion issued to avoid repetition of work for example: light curtain brackets, sensor mountings, cylinders, drilling tapping heads, motors, etc. Design numbering system is used to identify manufacturing parts. Common parts used in all machines identified with standard number. These part number gets engraved on part after manufacturing for easy identification. Design check sheet is followed to confirm all points.

Design Review:

To finalize the design and to check manufacturing feasibility, review meetings are arranged with customer and internal team. Members from all the functions such as eng

ineering, production, quality, safety, maintenance are part of this review. Machine is thoroughly assessed by the team to ensure that all aspects in terms of safety and quality are addressed. After finalization and sign-off, the parts are released for manufacturing. All data related to machine such as work order, product drawing, costing sheet, planning sheet, review signoff documents, part drawings, bill of material, quotations, assembly drawings etc. are documented.

Manufacturing of Parts:

Bill of material, part drawings, quotations of manufacturing parts and bought-out parts are shared with the sourcing team to place the orders. After purchase requisition and purchase order completion follow-up actions for timely delivery of parts is done with the vendors. The designer plays a key role in coordinating with the vendors and getting the parts manufactured per the design prints.

Machine Assembly:

After receipt of machine parts, thorough inspection is conducted to ensure that parts meet the specifications. This is verified before the start of assembly process so to make sure that the lead times are met. Machine assembly is done per plan. Team work’s into groups for timely completion of machine assembly. In-case there needs any corrections for the parts received, in-house tool room facility supports the modifications.

Control Panel Wiring and Installation:

Electrical team work in parallel for wiring of control panel as per electrical drawings provided by programmer. Identification tags are given to each cable. HMI is used to store the data. The sensor installation, FRL unit, cylinder, light curtain cabling programming is done in this process. As per the sequence of all operations, program is designed considering minimum interval of time.

Hydraulic Piping and Power pack installation:

Hydraulic cylinders and hydro power pack is installed at the later stage complying all pressure tests.

Trial & Commissioning:

Trials are conducted on machine to get required part specifications and cycle time. After number of trials, parts are inspected by QA. Safety audit is conducted by plant safety officer. After the approval from quality and safety the sign-off document for cycle time chart, inspection reports and safety audit report, machine is ready for handover to the production team. Training is provided to operator on machine operation and preventive maintenance practices. Plant members validate the machine and only then machine is shifted to specified plant for production.

Salient Features of Special Purpose Machines

• High Speed Spindles (RPM 4500 for reduced cycle times.
• SMED concept – changeover time between components is less than 5 minutes.
• Close positional tolerances of + / - 0.05 mm with Ra values 0.8 microns
• Hydraulic toggle link mechanism for rigid component clamping
• Heavy duty spindle mechanism
• Multi position milling for enhanced dimensional stability
• Lead screw tapping operation for precise pitch and thread dimensions
• Hydraulically operated chucks for centralising
• High productivity – 17 operations – 10 Sec – One Operator
• Multiple spindle operation
• Walking beam principle for component indexing
• Auto leak and flow checking
• Auto Good and Not-Good component sorting
• Robotic Pick and Place

Sigma Technology Centre Performance since Inception:

• Special Purpose Machines built and commissioned – 1313 Nos (Simple to Complex)
• Developed Holding & assembly Fixtures >1000 Nos
• Implemented Low Cost Automation Projects > 350 Nos
• Developed Heavy duty Machines > 20 Nos
• Installation of Robotics > 15 Nos
• Industry 4.0 Projects > 20 Nos
• Productivity Enhancement > 25%
• Operator Fatigue Eliminated by 90%
• Cost advantage over in-house SPM manufacturing > 40%
• Safety Enhanced by 100% (Zero accidents reported since last 28 months)