Precision Moulding: undocumented pressure changes and a chiller bought on price
Precision Moulding Ltd runs 40 injection moulding machines on three shifts, five days a week. Compressed air is 22% of site electricity. Over about eighteen months, operators have progressively raised the compressed-air header pressure from 6.5 bar to 7.5 bar because a few machines reject parts at lower pressure; no one recorded the reason and no document defines the correct pressure. The night shift routinely leaves 12 machines in idle mode for up to six hours. Compressor and chiller maintenance is outsourced to AirCare under a fixed-fee contract that specifies response times only, and AirCare technicians adjust set-points during service visits. A replacement 500 kW chiller is out to tender and will be evaluated on capital cost alone; the specification contains no energy performance criteria. Two energy champions were appointed in January; neither has been trained. A new paint line is at detailed design stage; its energy review is scheduled for after the equipment is specified and ordered.
1. Map these observations to clauses 8.1, 8.2 and 8.3, and distinguish nonconformities from improvement opportunities.
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8.1 Operational control - nonconformity. The standard requires criteria for the effective operation and maintenance of SEUs and communication of those criteria to relevant personnel. Compressed-air pressure is an operating criterion for a major SEU, and here it exists only as folklore. The rejection problem may well justify 7.5 bar; the nonconformity is that the requirement is undocumented, unapproved and unverified, not that the pressure is wrong. Idle machines for six hours is the same gap: no shutdown criterion, no owner.
8.1 Outsourced processes - nonconformity. AirCare adjusts set-points on equipment that drives two SEUs, under a contract with no energy criteria and no requirement to seek approval. The outsourced process is not controlled.
8.2 Design - nonconformity in the making. Design must consider energy performance improvement for new or modified facilities, equipment, systems and processes, with results documented as applicable. Scheduling the paint line's energy review after specification removes the only point at which the design can be influenced. Acting now - airflow, extraction, heat recovery, motor specification - is the remedy.
8.3 Procurement - nonconformity. Procuring energy-consuming equipment without energy performance specifications, and evaluating on capital cost only, fails 8.3. Include specific power or kW/TR at design conditions, part-load performance and life-cycle cost.
Opportunity: the pressure reduction itself may be recoverable once the rejecting machines are fixed.
2. What must change in the AirCare arrangement to satisfy 8.1, and how would you structure the requirement?
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8.1 requires the organization to ensure that outsourced processes affecting energy performance are controlled - or at minimum influenced - and that operating criteria reach the people doing the work, including contractor personnel.
Practical structure for the contract and the site:
- Scope the energy-relevant work. Compressor sequencing, set-points, condenser cleaning, leak detection and repair, dryer dew point. Name these explicitly.
- Attach criteria. Provide AirCare the operating criteria: target header pressure with tolerance, acceptable set-point ranges, sequencing logic, leak rate target, and the requirement that any change outside tolerance be approved by the site energy lead and logged.
- Performance indicators. Specify compressed-air specific power (kW per m³/min) or kWh per 1,000 standard cubic feet, reported monthly, plus leak repair closure rates. Fixed-fee response-time contracts reward nothing else.
- Competence and awareness. Require evidence that technicians know the criteria (7.2, 7.3) - a short induction plus a signed acknowledgement is enough.
- Verification. The site still verifies: monthly review of set-point logs, spot checks of pressure, review of AirCare reports at management review.
Rewriting the contract takes time, so issue an interim written instruction now. Waiting for the renewal date leaves the SEU uncontrolled for months.
3. Is appointing two untrained energy champions sufficient for clause 7.2? What else is needed for the roles to work?
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No. 7.2 requires the organization to determine the competence necessary for persons whose work affects energy performance, ensure those persons are competent, take action to acquire competence, and retain documented information as evidence.
Appointment creates a role, not competence. Neither champion can currently interpret the EnPI, run an energy review, challenge a set-point change or write an operating criterion - the exact tasks the role implies. Actions would be: define the competence profile for the role (EnMS fundamentals, ISO 50001 requirements relevant to their area, the site's SEUs and criteria, basic data analysis), assess the two individuals against it, and close the gap with training plus coached practice, e.g. each champion leads one SEU assessment under supervision. Record the profile, the assessment, the training and the evidence of application - a certificate alone is weak evidence; a completed SEU assessment signed by the champion is strong.
Two further points. First, 5.3: a champion without defined authority to stop an unauthorised set-point change will be ignored, so authorities need documenting and communicating. Second, 7.3 awareness: operators need to know how their work affects the SEUs and what the criteria are, otherwise the undocumented pressure rise simply recurs. Competence at the top of the pyramid without awareness at the bottom does not hold.