Automated Production Line for NTC Water-Temperature Sensor Intelligent Production Line

Project scope

We designed an intelligent automotive NTC water-temperature sensor production line concept. The line links NTC lead welding, connector and housing assembly, high-temperature curing, riveting, laser marking, electrical tests and final transfer into a controlled sequence. That makes the scope an automated Production Line application for ntc water-temperature sensor welding, assembly, curing, riveting and testing.

The confirmed planning target is 240 to 260 pcs/hour. The project data also defines an overall staffing reference of 6 operators, with an average of 3 operators watching machines and 3 operators handling material transfer and inspection. Investment amount, ROI and payback period are not confirmed in the available project data, so they are not claimed for this case.

Connecting multiple sensor processes

The product route is not a single machine task. It has to combine manual NTC loading, connector pin crimping, DC welding, continuity and visual inspection, housing glue dispensing, O-ring placement, NTC insertion, curing, riveting, marking, insulation checks and resistance comparison.

Keeping trays accurate enough for automation

The trays must locate both the NTC wire and the connector. The NTC needs limiting on the connector-pin side and outside the pin, a compression device to keep the wire centered on the pin, and a head stop to control the assembled length. The same tray strategy also has to allow future changeover for other low-temperature sensor products.

NTC welding and tray preparation

The welding section uses manual NTC loading into trays, automatic connector feeding into trays, pin crimping, NTC DC welding, room-temperature resistance testing, welding visual inspection and sorting of good and NG parts.

The equipment layout can use a rotary-table structure. The loading takt target is no more than 5 seconds per piece, with 1 operator. The design also reserves space for future automatic NTC loading so the line can be upgraded without rebuilding the process from scratch.

Welding section item	Confirmed specification
Loading takt target	No more than 5 seconds per piece
Operator requirement	1 operator
Welding method	DC welding
Weld action	One weld point per action
Weld evaluation	Axial and radial pull force not lower than the NTC wire-body pull force
Vision requirement	Camera with deep-learning capability
Pin crimping	Program-adjustable crimping degree with pre-crimp vision check

Front assembly line

The front assembly process starts with housing trays and O-rings, then aligns the connector-NTC assembly, dispenses high-temperature glue at the probe, places the inner O-ring, inserts the NTC into the housing and transfers the housing into a high-temperature tray for curing.

The front assembly takt target is no more than 15 seconds per piece with 1 operator. The tray uses a hexagonal locating structure and needs to support switching to similar low-temperature sensor products.

Front assembly item	Confirmed specification
Cycle target	No more than 15 seconds per piece
Operator requirement	1 operator
Glue dispensing control	Online weighing before and after dispensing, with alarm below the lower limit
Dispensing hardware	Pneumatic syringe dispensing, AP-III air-pressure controller and stainless long needle
Needle correction	Fiber-based automatic correction after glue change
Motion control	3-axis M-control dispensing controller with automatic needle alignment
Needle cleaning	Periodic wiping on dust-free cloth with configurable interval
Curing profile	80 degrees C for 10 minutes preheating, then 150 degrees C for 30 minutes curing

Rear assembly, marking and testing

The rear line handles the cured housing tray, riveting with dot marking, laser marking, hipot testing, room-temperature resistance testing, external O-ring assembly and final tray unloading. A six-axis robot transfer concept is used in the rear process section.

Rear line item	Confirmed specification
Cycle target	No more than 15 seconds per piece
Operator requirement	1 operator
Riveting concept	Spring-compressed connector with servo-cylinder riveting structure
Riveting monitoring	Stroke and displacement monitoring
Laser marking materials	Metal, PBT+GF30, PPS+GF30 and PP+GF30
Laser head adjustment	X, Y and Z movement with locking
Hipot range	24V to 500V, with 100V listed as the specific value
Resistance test condition	Room-temperature air test with a 4.02 KOhm pull-up resistor considered
Data traceability	Resistance data mapped one-to-one to the laser-mark sequence number

Resistance and temperature validation

The resistance check compares the product with a nearby standard sample after both have reached stable air temperature. The standard sample requires periodic calibration. The concept also includes an external high-temperature oil or water bath test station for thermal validation.

Reference parameters

The confirmed parameter table defines the main modules and utilities as planning references. Dimensions are reference values and remain subject to final mechanical design.

Item	Confirmed specification
NTC automatic welding module	2100 x 1000 x 1950 mm reference size
NTC assembly line	2270 x 1500 x 1950 mm reference size
NTC riveting and testing line	2600 x 1500 x 1950 mm reference size
Conveyor/aisle reference	7000 x 2000 x 1600 mm reference size
Electrical and air supply	AC220V, 380V, 0.6 to 0.8 MPa
Planned capacity	240 to 260 pcs/hour
Control platform	Host computer, PLC, vision and robot integration
Overall staffing reference	6 operators

Proposed operating result

The resulting concept turns a multi-step NTC sensor process into a connected production route. Welding, crimping, assembly, curing, riveting, marking and electrical checks are planned as coordinated modules rather than isolated stations.

Process value

  The value is in stabilizing process handoff. Trays preserve NTC and connector position, vision checks control welding and insertion risk, glue quantity is checked by online weighing, laser-mark data is tied to resistance results, and the line has a confirmed 240 to 260 pcs/hour planning range. The project data includes manual-line labor and equipment-budget comparison pages, but the OCR is partially corrupted, so we avoid using those figures as ROI evidence.