What should be paid attention to during the installation and debugging of hoisting and conveying machinery?

The installation and debugging of lifting and conveying machinery (such as bucket elevator, belt lifting conveyor, screw elevator, etc.) directly determines the stability, safety and service life of the equipment, and should be controlled around four core links: foundation positioning, component assembly, safety protection and no-load/load debugging. The specific precautions are as follows:

Preparation before installation and foundation acceptance

Inspection of site and foundation: the foundation shall be constructed according to the design drawings, with flatness error ≤3mm/m, and the bearing capacity shall match the full load of equipment (for example, the bearing capacity of heavy bucket elevator foundation ≥ 10t/㎡); Check that the position deviation of foundation embedded parts (bolts and steel plates) is ≤±2mm, so as to ensure accurate docking with the hole position of equipment base.

Unpacking acceptance of equipment: check the model and quantity of components such as frame, hopper, conveyor belt/chain and motor reducer, and check whether key components (such as bearings and sprockets) are damaged or corroded; Clean the rust-proof oil and dust on the surface of parts, especially the transmission and connection parts.

Tools and safety preparation: equipped with high-precision tools such as laser locator, level meter and torque wrench; Designate the safe installation area, set warning signs, and erect scaffolding and fasten your seat belt for high-altitude installation.

Assembly requirements of core components

Installation of frame and guide rail

When the racks are spliced in sections, it is necessary to ensure that the verticality deviation is ≤1‰ (within the full height range) and the lateral horizontal deviation is ≤ 0.5 ‰; The bolts at the splice should be tightened according to the specified torque (refer to the manufacturer's manual), and check washer should be installed to avoid loosening during operation.

The hopper guide rails of bucket elevator should be installed in parallel, and the distance deviation between the guide rails on both sides should be ≤±1mm to prevent the hopper from being stuck and running off.

Transmission system assembly

The coaxiality deviation of motor, reducer and spindle shall be ≤0.1mm, and sufficient compensation clearance (0.5~1mm) shall be reserved when installing the coupling to avoid vibration damage caused by rigid connection.

The installation of sprocket and roller shall ensure that the end face runout is ≤0.2mm, and the fit with the spindle shall be interference fit or key connection to ensure the stability of power transmission.

Conveying component assembly

The hopper of bucket elevator should be fixed on the chain/belt evenly, and the bolts should be spot-welded to prevent loosening after tightening; The deviation of hopper spacing shall be ≤±2mm, so as to prevent collision with the rack during operation.

The conveyor belt joint of the belt lifting conveyor shall be smooth and firm (the strength of cold bonding joint shall be 90% or higher than that of the original belt, and the strength of hot vulcanization joint shall be 95% or higher than that of the original belt) to avoid deviation and cracking at the joint.

The clearance between the spiral blade of the spiral hoist and the inner wall of the barrel should be uniform (5~10mm on one side), and there should be no virtual welding and cracks at the welding place of the blade to prevent material blockage or blade wear.

Safety protection and auxiliary system installation

Installation of protective device: protective fence and maintenance platform need to be installed outside the frame; The material inlet and the material outlet are provided with overflow-proof baffles; High-speed running parts (sprockets and pulleys) need to be equipped with protective covers to prevent them from being involved in foreign objects or being injured by personnel.

Electrical and control system installation: the motor should be grounded (grounding resistance ≤4Ω), and the power cable should be protected through the tube to avoid rubbing against moving parts; Install sensors such as overload protection, deviation protection and material level detection to ensure reliable linkage with the control cabinet.

Commissioning of lubrication system: add lubricating oil (grease) as required, ensure adequate lubrication of bearings, sprockets and other parts, and ensure no leakage of lubrication pipeline; Make clear the lubrication cycle of different parts (for example, the bearings are filled with lithium grease once a month).

Key steps of no-load debugging

Inspection before trial operation: turn the car manually for 2~3 turns to check whether there is sticking or abnormal sound; Confirm that all bolts are fastened in place, and sensors and limit switches are sensitive; Clean the sundries in the machine to ensure there are no obstacles.

No-load operation parameter control

Inch the motor, and observe whether the running direction of the equipment is correct (reverse rotation is strictly prohibited), whether the conveyor belt/hopper deviates, and if it deviates, adjust the tensioner of the roller/sprocket.

Run continuously for 2~4 hours without load, monitor bearing temperature (≤70℃) and motor current (≤ 60% of rated current), and the running noise shall be ≤ 85dB; Record operation data, and troubleshoot problems such as vibration and abnormal sound.

Adjust the tension: the tension of conveyor belt/chain should be moderate, too tight will increase the motor load and parts wear, too loose will easily lead to slipping and deviation; After adjustment, it is necessary to tighten the bolt of the tensioner again.

Load debugging and acceptance standard

Step-by-step loading test: firstly, load 30%, 50%, 80% and 100% of the rated load step by step, with each load running for 1 hour, and monitor the motor current, equipment vibration and material conveying stability.

Acceptance of key indicators

The material conveying capacity should reach more than 95% of the design value; The hopper and conveyor belt have no obvious deviation and material scattering.

Bearing temperature rise ≤40℃ (above ambient temperature), motor has no overload and heating, and the protection function of control system (overload and deviation alarm) is accurate.

Abnormal handling: if there is material blockage, it is necessary to stop the machine immediately to clean it up, and investigate the reasons such as excessive feed rate and poor discharge port; In case of chain/belt jumping, check the tension or frame verticality.

Acceptance and delivery after commissioning

Arrange installation and debugging records (basic acceptance, component assembly, no-load/load operation data) and form an acceptance report; Train the operators and make clear the main points of daily maintenance and troubleshooting.

The equipment manual, warranty card and list of wearing parts shall be provided at the time of delivery, and the users shall be informed of the key parts for regular inspection (such as chain tension and hopper wear).