PLC and CNC automation

Repeatability is the product

A skilled operator with a flame torch can harden a shaft correctly. What they cannot do is harden four hundred of them per shift to the same case depth, on a Friday afternoon, on the third shift, after a machine change. The variability is not a failure of skill; it is what happens when a process depends on human judgement.

A PLC does not get tired and does not estimate. It holds power, time, traverse speed, rotation and quench timing to the same values every cycle, and it does so whether or not anyone is watching. When a customer is sectioning parts and measuring case depth against a drawing tolerance, that consistency is the thing they are actually buying.

What gets controlled

• Power and heating time. The energy into the part, held constant cycle to cycle.
• Traverse speed. On a scanner this sets the case depth along the length. It is the parameter most likely to drift under manual control.
• Rotation. Turning the part under the coil evens out any asymmetry in the field. Speed and start point both matter.
• Quench timing and flow. How long after heating the quench arrives, and for how long. Get this wrong and the case is right but the hardness is not.
• Temperature, where a pyrometer is fitted. Closed loop on measured temperature rather than open loop on a timer, so parts arriving warm and parts arriving cold both finish correct.
• Interlocks. Coolant flow, water temperature, guard position, part presence. The machine refuses to run when a condition is not met, rather than producing a bad part.

Programs, not settings

We equip our PLC controlled vertical scanner with programs for different components. We develop and set up the process for the part and production requirements you provide.

A shop rarely runs one part. It runs a family of them, and each one has its own power, speed and quench timing. Storing those as named programs means the changeover is a selection rather than a setup, which removes the most common source of scrap: someone remembering last week's numbers slightly wrong.

How much automation is worth it

More automation is not automatically better. It costs money, it adds things that can fail, and beyond a point it stops paying for itself. Three honest guides:

• Manual suits low volume, high variety and development work. The operator is the flexibility.
• Semi-automatic suits most production. The operator loads and unloads; the machine owns the cycle. This is where the repeatability gain is largest per rupee spent.
• Fully automatic suits high volume on a stable part family, where handling and loading are genuinely the bottleneck rather than the heating.

The double station machines We build sit deliberately in the middle band: two stations mean the power supply is working while the operator loads the other side, which roughly doubles throughput without adding a robot.

What we build

We build PLC and CNC controlled automatic induction machines, including vertical and horizontal hardening systems, double station machines and rotary indexing systems.

In practice that has produced vertical and horizontal scanners, single and double station machines, rotary indexing bonding machines, fully automatic CI ring heating stations working on measured temperature, and dedicated cells for flywheel rings and hammer heads.