80+ Senior Engineer- Maintenance Interview Questions and Answers

Answering questions related to maintenance and engineering

• Maintenance is crucial for ensuring the smooth functioning of machines and equipment

• Yes, I have experience in maintaining high power UPS systems

• Regular maintenance and timely repairs can reduce the n/d time of plant machines

• Yes, I have experience in in-house repair of VFDs and programming/commissioning

• I report to the Maintenance Manager or Plant Manager

• Yes, I have experience in calibrating process controllers

• The number...read more

Yes, I have knowledge of robot, press mc, thermoforming, Thermosetting, heater, oven, and utility.

• I have experience in maintaining and troubleshooting robots used in manufacturing processes.

• I am familiar with press machines and have worked on their maintenance and repair.

• I have knowledge of thermoforming processes and have worked on maintaining the equipment used in it.

• I am familiar with Thermosetting processes and have experience in maintaining the equipment used in it.

• I hav...read more

PLCs have various types of inputs and outputs for communication and control.

• PLCs have digital inputs and outputs for binary signals.

• Analog inputs and outputs are used for continuous signals.

• Specialized inputs and outputs include high-speed counters, pulse outputs, and communication modules.

• Examples of PLC input devices are push buttons, limit switches, and sensors.

• Examples of PLC output devices are motors, solenoids, and lights.

The pH of boiler feed pump water varies depending on the type of water treatment used.

• The pH of untreated water is typically around 7.0 (neutral)

• Water treatment chemicals can affect the pH of the water

• The ideal pH range for boiler feed water is between 8.5 and 9.5

• Maintaining proper pH levels can prevent corrosion and scaling in the boiler system

There are various types of bearings used in spindle assembly including ball bearings, roller bearings, and angular contact bearings.

• Ball bearings are commonly used in spindle assemblies due to their high load capacity and low friction.

• Roller bearings are used for heavier loads and can handle both radial and axial loads.

• Angular contact bearings are used for high-speed applications and can handle both radial and axial loads.

• Ceramic bearings are also used in some spindle assembl...read more

Hydraulic and pneumatic systems are used to transmit power using fluids or gases.

• Hydraulic systems use liquids such as oil to transmit power.

• Pneumatic systems use gases such as air to transmit power.

• Both systems use pumps or compressors to generate pressure.

• Hydraulic systems are commonly used in heavy machinery such as excavators and cranes.

• Pneumatic systems are commonly used in tools such as drills and impact wrenches.

PLC program for automatic water tank fill up with indicators

• Define input sensors for water level and output actuators for water fill valve

• Create ladder logic to control the fill valve based on water level sensors

• Add indicators to display water level and fill status

• Test and debug the program to ensure proper functionality

Direct drive spindle is directly connected to the motor while belt drive spindle uses a belt to transfer power.

• Direct drive spindle has higher accuracy and faster response time.

• Belt drive spindle is less expensive and easier to maintain.

• Direct drive spindle is commonly used in high-end machines while belt drive spindle is used in low to mid-range machines.

• Examples of direct drive spindle machines include Mazak Integrex and Okuma Multus while examples of belt drive spindle mac...read more

Yes, I am knowledgeable about Programmable Logic Controllers (PLC) and electrical troubleshooting.

• I have experience working with various PLC systems such as Siemens, Allen Bradley, and Mitsubishi.

• I am proficient in reading and interpreting ladder logic diagrams.

• I have successfully diagnosed and resolved electrical issues in industrial machinery using PLCs.

• I am familiar with troubleshooting sensors, actuators, and other electrical components in automated systems.

I handle various types of packing machines in my role as a Senior Engineer- Maintenance.

• Handling vertical form fill seal machines

• Operating carton sealing machines

• Maintaining shrink wrapping machines

• Troubleshooting case packing machines

Bearing number 6205 2z refers to a sealed deep groove ball bearing.

• 6205 2z indicates a deep groove ball bearing with metal shields on both sides

• The '2z' in the bearing number signifies the type of sealing, in this case metal shields

• This type of bearing is commonly used in applications where protection from contaminants is required

Yes, I have knowledge of utility.

• I have experience in maintaining and repairing utility systems such as HVAC, plumbing, and electrical systems.

• I am familiar with safety protocols and regulations related to utility systems.

• I have worked with various types of utility equipment and tools.

• I have knowledge of energy efficiency and sustainability practices in utility systems.

• I am able to troubleshoot and diagnose issues with utility systems and develop effective solutions.

If a mold is not open, it can lead to various operational and safety issues in maintenance.

• Increased pressure buildup: If a mold is not vented, it can cause pressure to rise, leading to potential equipment failure.

• Quality defects: Closed molds may result in incomplete filling, causing defects in the final product.

• Safety hazards: Overpressure can lead to dangerous situations, including explosions or leaks of hazardous materials.

• Increased cycle time: If molds are not functionin...read more

Diesel engines are internal combustion engines that use diesel fuel, known for efficiency and durability in various applications.

• Uses compression ignition: Air is compressed to high pressure, raising temperature to ignite fuel.

• Fuel injection: Diesel is injected directly into the combustion chamber at high pressure.

• Higher thermal efficiency: Diesel engines typically achieve 30-40% efficiency, better than gasoline engines.

• Durability: Built to withstand higher pressures and temp...read more

The cenifuse machine is used for centrifugation, a process that separates substances of different densities.

• Centrifugation is a technique used in various industries, including biology, chemistry, and healthcare.

• The cenifuse machine spins samples at high speeds to generate centrifugal force.

• This force causes heavier particles to move towards the bottom while lighter particles move towards the top.

• The separated substances can then be collected and analyzed separately.

• In medical...read more

The question is about injection molding machine parts, working, and control system I/O interface, hydraulic motor types, and star delta working.

• Injection molding machine parts include the hopper, barrel, screw, nozzle, mold, and clamping unit.

• The control system I/O interface includes sensors, switches, and actuators.

• Hydraulic motor types include gear, vane, and piston motors.

• Star delta working is a method of starting and stopping three-phase motors.

Calculate reactive panel capacity to improve power factor by balancing inductive loads with capacitive compensation.

• Identify the total active power (kW) and reactive power (kVAR) of the load.

• Use the formula: Power Factor (PF) = kW / √(kW² + kVAR²).

• Determine the desired power factor (e.g., 0.95) and calculate the required kVAR.

• Calculate the reactive power needed using: kVAR_required = kW * (tan(acos(desired PF)) - tan(acos(current PF))).

• Example: For a 100 kW load with a curren...read more

Preventive maintenance is a proactive approach to maintenance that involves regularly scheduled inspections, repairs, and replacements to prevent equipment failure.

• Regularly scheduled inspections to identify potential issues before they become major problems

• Routine cleaning and lubrication to keep equipment running smoothly

• Replacing worn out parts before they fail to prevent costly breakdowns

• Creating a maintenance schedule based on manufacturer recommendations and equipment u...read more

Fuel consumption of a rotary furnace varies based on design, material, and operational conditions, impacting efficiency and costs.

• Fuel Type: Rotary furnaces can use various fuels, including natural gas, oil, or electricity, affecting consumption rates.

• Operational Efficiency: The efficiency of the furnace, often measured in terms of heat recovery, can significantly influence fuel consumption.

• Material Characteristics: The type of material being processed (e.g., metal, glass) ca...read more

Press machines use hydraulic or mechanical force to shape or cut materials.

• Press machines use a ram or piston to apply force to a material.

• Hydraulic press machines use fluid pressure to generate force.

• Mechanical press machines use a flywheel or motor to generate force.

• Press machines can be used for stamping, forging, punching, and more.

• Safety precautions must be taken when operating press machines to prevent accidents.

Tracing the root cause of an emergency alarm involves systematic investigation and analysis of the alarm system and its components.

• Initial Assessment: Quickly assess the alarm to determine if it is a false alarm or a genuine emergency, checking for any immediate hazards.

• Review Alarm History: Analyze the alarm logs to identify patterns or recurring issues that may indicate a specific problem, such as equipment failure.

• Inspect Alarm Components: Physically inspect the alarm syst...read more

I have extensive experience with various industrial machines, including CNC machines, conveyor systems, and hydraulic presses.

• CNC Machines: Operated and maintained CNC lathes and mills for precision manufacturing.

• Conveyor Systems: Worked on troubleshooting and optimizing conveyor belt systems in a production line.

• Hydraulic Presses: Conducted regular maintenance and repairs on hydraulic presses used for metal forming.

• Pumps and Compressors: Experience with centrifugal pumps and...read more

In critical situations, production planning involves prioritizing tasks, allocating resources efficiently, and communicating effectively.

• Identify the root cause of the critical situation

• Prioritize tasks based on impact on production and safety

• Allocate resources effectively to address the critical issues

• Communicate clearly with all stakeholders to ensure coordinated efforts

• Develop contingency plans for potential scenarios

In a parallel circuit, components are connected in separate branches, allowing current to flow through multiple paths. In a series circuit, components are connected in a single path, where current flows through each component in sequence.

• Parallel circuit allows current to flow through multiple paths, while series circuit has only one path for current.

• In a parallel circuit, voltage across each component is the same, while in a series circuit, voltage is divided among component...read more

A power pack is a device that converts mechanical energy into electrical energy. Its main components include an engine, generator, and control system.

• Power pack converts mechanical energy into electrical energy

• Main components include engine, generator, and control system

• Engine provides mechanical energy to generator

• Generator converts mechanical energy into electrical energy

• Control system regulates the power output

SAP T-codes are transaction codes used in SAP systems to execute specific functions.

• T-code SM01 is used to lock/unlock transactions

• T-code SE11 is used to create or modify database tables

• T-code MM01 is used to create a material master record

• T-code VA01 is used to create a sales order

• T-code FBL3N is used to display GL account line items

A circuit diagram converting 230v ac to 24v dc.

• Use a step-down transformer to reduce voltage from 230v ac to a lower voltage.

• Rectify the AC voltage using a bridge rectifier to convert it into pulsating DC.

• Filter the pulsating DC using capacitors to smoothen the output.

• Regulate the DC voltage using a voltage regulator to maintain a steady 24v output.

• Example components: Step-down transformer, bridge rectifier, capacitors, voltage regulator.