Cable Tray Forming Machine

Machine de formage de rouleaux de chemins de câbles

Cable Tray Forming Machine

Cable Tray Forming Machine

Machine de formage de rouleaux de chemins de câbles

This document is designed for universal cold bending machines used with C-beams, Z-beams, U-beams, and purlins. It categorizes issues into five major types—defects in finished product formation, feeding system malfunctions, precision cutting errors, mechanical operation failures, and electrical control system failures—and provides corresponding solutions: temporary emergency measures, standard corrective actions, and preventive maintenance plans, making it ideal for frontline workshop operations.

Forming defects in finished profiles (the most common type of failure)

Profile distortion, lateral bending, and arching

Malfunction: The finished product exhibits full section torsion, unilateral outward bending, central arching, and cross-sectional angle deviation, making it unable to fit the installation reference.

Key causes:

① Asymmetric left-right gaps and frame misalignment of each forming roll;
② Excessive pressure on a single roll set leading to internal stress imbalance in the sheet;
③ Improper distribution of bending angles across forming passes, resulting in excessive deformation at the first bend;
④ Uneven thickness and significant hardness variation across batches of raw steel strips;
⑤ Inconsistent height differences between discharge rollers causing inclined loading during material discharge.

Solution ：

Emergency procedure: Stop operation to calibrate the bilateral gaps of each roll set, ensuring consistent roller clearances on both sides at the same workstation; make fine adjustments to unilateral pressure relief and release internal stresses in the sheet metal.

Rectify and reform: Level all forming frames using a level; adjust the coaxiality of the drive shaft; reconfigure the bending path angles; reduce the deformation amplitude in the initial bending stage.

Prevention: Standardize the material and thickness tolerances of the feeding steel strip; adjust the height of discharge rollers, and install limiters and anti-deviation guide wheels.

The cross-sectional dimensions of the profile exceed the specified limits; the edge heights are inconsistent; and the angles do not meet the required standards.

Fault phenomenon：The steel profile flanges vary in height and length; the bending angles are either too large or too small; the opening dimensions exceed tolerance limits, resulting in batch-wide nonconformities.

Core Causes：

① Roll wear, surface chamfering, or deformation;
② Loose roll locking bolts causing operational displacement;
③ Misalignment of feed guide plates resulting in improper steel strip feeding;
④ Fluctuating servo feed speed leading to unstable forming forces.

Solution：

Testing：Measure the finished cross-section section by section using a caliper, compare it with the roller at the most worn position, and mark the replacement point.

Rectify and reform ：Tighten all roller lock nuts and frame mounting bolts; recalibrate the feeding guide plate to center it; grind or repair lightly worn rollers, and replace severely worn rollers with matching tooling rollers.

Paramètres ：Standardize the feeding speed across the entire line; prohibit frequent switching between high and low speeds during molding.

The profile surface exhibits scratches, dents, and peeling.

Fault phenomenon：Continuous scratches on both sides of the steel strip, punctate pressure pits, and galvanization layer detachment, compromising both corrosion resistance and appearance.

Core Causes：

① Iron chips, welding slag, and oxide scale adhere to the roller surface;
② The roller surface is corroded with burrs and sharp edges;
③ The guide wheel lacks sufficient hardness, causing jamming and material scraping;
④ Lubrication-free forming results in dry friction-induced damage to the plate surface.

Solution：

Daily：Stop the machine to clean all roller and guide wheel surfaces of metal chips and impurities, then use an oil stone to remove surface burrs.

Rectify and reform ：Replace the damaged guiding nylon wheel to prevent severe metal friction; apply specialized forming lubricant to galvanized steel profiles during molding.

Management and control：During raw material intake and storage, remove oxide slag from the steel strip surface; install a dust removal and slag scraping plate before feeding.

The profile plate exhibits surface bulging and internal creases.

Fault phenomenon：wrinkling occurs at the rounded corners of bending, with localized blistering on the plate surface; this phenomenon is highly prevalent in thin-walled steel sections.

Cause&Solution：Excessive roller pressing force → Reduce the rolling stroke per station; Insufficient bending radius → Replace with a roller featuring larger radius; Excessive feeding tension → Release the material feeding/discharging damping device

Malfunctions related to delayed material feeding

The steel strip deviates during feeding, and material flows off to one side.

Cause：The feed guide groove is eccentric; the pressure from the upper and lower rollers is uneven on both sides; the wound coil is eccentric; and the ground frame is tilted.

Solution：Adjust the bilateral feed guide plates centrally; evenly adjust the pressure adjustment spring of the feed roller; install a centering and tightening device on the material roll; re-level the equipment base.

Frequent material jams, blockages, and situations where the steel strip bends and gets stuck at certain processing stations.

Cause：

① The gap between the first forming roller is too small;
② Waste material from irregular edges or corners is trapped within the roller gap;
③ The overlap thickness of steel strip joints exceeds the specified limit;
④ The speed ratio between the feeding motor and the forming roller is incorrect.

Solution：Increase the gap between the initial forming rolls; perform scheduled cleaning of waste materials at the processing station; grind and flatten steel strip joints before feeding; ensure electrical control synchronization between feeding speed and forming rotation speed; install an overload-based reverse feeding program.

The feeding mechanism is slipping; the material feed is rotating without movement; the lengths of the profiles vary.

Cause：The shipping roller exhibits smooth wear, insufficient pressing force, and oil contamination on its surface; the steel belt surface also becomes slippery due to oil contamination.

Solution：Polish the surface of the feed roller and adjust the clamping pressure; wipe off oil stains from the roller surface and steel belt; replace worn rubber rollers with anti-slip patterned rollers.

Cut length fixed, punching failure

The final product’s length does not meet the specified dimensions, and there are variations in length across batches.

Cause：Encoder offset; loss of counting parameters; displacement caused by feeding slip; zero point offset of the cutting servo; incorrect modification of PLC length parameters

Solution：Encoder offset; loss of counting parameters; displacement caused by feeding slip; zero point offset of the cutting servo; incorrect modification of PLC length parameters

The hydraulic cutting tool exhibits significant burr on the cutting surface, skewed cuts, and chip breakage.

Cause：Excessive clearance between the upper and lower cutting blades; dulled cutting edges; failure to adjust clearance when cutting steel of varying thicknesses; excessively high hydraulic descent speed causing impact on the cutting edge.

Solution：Fine-tune the cutting blade fit clearance; grind and polish the cutting edge; replace the alloy cutting blade; set the cutting gap according to thickness requirements; adjust the hydraulic throttle valve to reduce the downward cutting speed.

Hole position deviation, hole diameter deformation, punching tear

Cause：Misalignment of punching die; wear of die core; failure to center the profile after forming; excessive hydraulic punching pressure

Solution：Ibrate the punching die for coaxiality; install a punching limit fixture; replace the worn punch and die; reduce the hydraulic pressure for punching

Mechanical transmission failure; frame operation malfunction

Abnormal noises during device operation, at specific locations, or under load

Fault Point Identification：

Chain abnormal noise：Chain slack, oil deficiency, tooth wear → Tension the chain, apply gear oil, replace worn sprockets

Abnormal noise at the roller shaft station：Lubrication deficiency in the bearing, damaged balls, excessive clearance in the bushing → Replace the bearing and apply high-temperature resistant grease.

Load friction noise：Rolls are misaligned and rub against each other; the profile also rubs against the frame → The parallelism of the roller assembly needs to be recalibrated.

Significant body vibration, operational shaking, and base displacement

Cause：Coaxiality deviation of the drive shaft; loose coupling; aging of the base shock absorber pads; uneven force distribution across multiple roller sets; loose motor mounting bolts

Solution：Ibrate the drive shaft concentricity and tighten the coupling; replace the shock-absorbing foot pads; evenly distribute forming pressure across all stations; tighten the bolts on the main motor base.

Hydraulic system oil leakage, insufficient pressure, inadequate cutting force

Cause：Aging of the oil seal ring, insufficient hydraulic oil level, clogged filter element, wear of the hydraulic pump, and failure of the relief valve pressure regulation.

Solution：Replace all oil seal rings; add hydraulic oil of the same grade with wear-resistant properties; clean the hydraulic filter element regularly; adjust the operating pressure of the relief valve; replace the hydraulic pump directly when pressure attenuation occurs in the pump body.

Malfunctions in the electronic control and frequency conversion systems

The device experiences lag during startup and shutdown, along with an overload alarm for the frequency converter.

Cause：Excessive load during forming operation; mismatched motor power; insufficient current limiting parameters in the frequency converter; aging wiring causing short circuits; motor stalling due to jammed workstations.

Solution：Reduce the pressure on individual rolls; increase the overload protection threshold of the frequency converter; inspect the power circuit; install an overload shutdown protection program for machine idling.

Touch panel parameters are malfunctioning with random data fluctuations

Cause：Electromagnetic interference in the workshop, loose wiring on the panel, malfunctioning PLC program, and unstable power supply voltage.

Solution：Install shielding grounding wires on the electrical control cabinet; secure communication wiring terminals; power down and restart the PLC for reset; install a voltage stabilizer to accommodate fluctuating workshop voltages.

Emergency stop failure; limit switch malfunction

Cause：The travel switch is blocked by metal shavings; the wiring is broken; and the contacts are oxidized.

Solution：Clean the sensor contact points; replace the waterproof limit switch; regularly check the safety circuit’s operation.

Key Principles of Universal Preventive Maintenance (Reduce Failures by 80%)

Daily pre-shift tasks: Clean iron debris from the rolls, check hydraulic fluid level, and test the emergency stop limit function.

Weekly: Apply grease to chains and bearings, and verify the dimensional accuracy of all profiles.

Monthly: Adjust the rack level, tighten all vehicle bolts, and calibrate the encoder’s zero point.

Material control: The use of steel strips with thickness deviations, excessive joint overlap, or severe corrosion is strictly prohibited during production.