Technological advancement promotes operational excellence by allowing manufacturers to develop new products that can be cost-competitive compared to 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 technological advancement will have the most significant 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 with significant engineering capabilities is manufactured with highly customized machinery and extensive robotics utilization, which boosts overall productivity & quality performance and reduces cost.

The technology centre is equipped with a modern design facility and software with an experienced design team with sound knowledge of design in mechanical assemblies, hydraulics, pneumatics, mechatronics, electrical systems, robotics, and automation. The centre is also equipped with an in-house PLC programming facility, assembly shop used to avoid repetitive work, for example, light curtain brackets, sensor mountings, cylinders, drilling tapping heads, motors, etc. A design numbering system is used to identify manufacturing parts. Common parts are used in all machines identified with a standard number. These part numbers get engraved on the part after manufacturing for easy identification. A design check sheet is followed to confirm all points.

Design Review:

To finalize the design and check manufacturing feasibility, review meetings are arranged with the customer and internal team. Members from all the functions such as engineering, production, quality, safety, maintenance are part of this review. The machine is thoroughly assessed by the team to ensure that all aspects of safety and quality are addressed. After finalization and signoff, the parts are released for manufacturing. All data related to machines 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 components is done with the vendors. The designer plays a crucial role in coordinating with the vendors and getting the parts manufactured per the design prints.

Machine Assembly:

After receipt of machine parts, a thorough inspection is conducted to ensure that parts meet the specifications. This is verified before the start of the assembly process to make sure that the lead times are met. Machine assembly is done per plan. The team works into groups for timely completion of tool room, test equipment, IOT laboratory, and Cobot simulation center 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. The cost centre number is generated for the identification of machines. The plan for the machine completion is of the machine. Depending on the complexity of the machine, the plan is designed. The concept is designed based on inputs given by the customer. In basic, concept design feasibility check is done by a cross-functional team. If a similar type of machine is available in the 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 is the tool room, test equipment, IOT laboratory, and Cobots simulation centre to explore various trials and process design, which helps for speedy machine assembly. In-case there needs any corrections for the parts received, the in-house tool room facility supports the modifications.

Control Panel Wiring and Installation:

Electrical teams work in parallel, wiring control panel as per electrical drawings provided by the 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, the program is designed considering a minimum interval of time.

Trial and Commissioning:

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

Salient Features of Special Purpose Machines (SPM’s)

• 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 centralizing

• 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

Hydraulic Piping and Power Pack installation:

Hydraulic cylinders and the hydropower pack are installed at the later stage, complying with all pressure tests.

Sigma Technology Centre Performance since Inception:

• Special Purpose Machines built and commissioned – 1313 Nos (Simple to Complex)

• Developed Holding and 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 percent

• Operator Fatigue Eliminated by 90 percent

• Cost advantage over in-house SPM manufacturing > 40 percent

• Safety Enhanced by 100 percent (Zero accidents reported since last 28 months).