Efficient Rotary Dryer Installation and Operation: A Comprehensive Guide for Easy Setup and Smooth Performance

Unlock the full potential of your rotary dryer with our comprehensive installation and operation guide. Whether you're a seasoned professional or new to the world of industrial drying, this guide is tailored to ensure seamless setup and optimal performance.

Essential Guidelines for Lime/fertilizer Industrial Dryer Installation:

Pre-installation Preparations:

The installation of an industrial dryer, a cornerstone piece of mineral processing equipment, demands adherence to rigorous technical specifications and elevated process standards. Proper installation procedures must align meticulously with relevant design documents, drawings, and industry-standard protocols outlined in this guide.

Foundation Inspection: Thoroughly assess the quality of the foundation concrete, meticulously checking for deviations in size and positioning. The foundation’s surface must be immaculate, devoid of oil, dust, debris, and any structural imperfections such as cracks or exposed steel bars. Verify the absence of residual shell plates in designated areas. Tolerances for dimensional and positional deviations should not exceed 20mm, with strict adherence to vertical and horizontal axes. Elevation errors across different planes should be within 20mm, exclusively negative deviations permitted. Slope errors should not exceed 20mm over the total length, with no misalignment allowed at the discharge end. Additionally, ensure the upper plane’s unevenness does not surpass 5mm/m, with a total length discrepancy of less than 10mm.
Equipment Verification: Cross-reference the equipment packing list provided by the manufacturer to confirm the presence and integrity of all components. Scrutinize for discrepancies, missing parts, deformities, or damages incurred during transit. Remove protective coatings and eliminate any traces of dust, oil, or rust. Conduct pre-inspections and, if necessary, pre-assemble key components to preempt installation setbacks and ensure seamless progress and quality.
Preparation and Installation Procedures: Establish a comprehensive plan delineating the sequence for parts cleaning, testing, transportation, assembly, adjustments, and trial operations.
Develop detailed methodologies for inspecting and installing critical components, specifying quality requirements, technical standards, permissible deviation ranges, and requisite tools.
Prioritize safety by formulating and enforcing precautionary measures to mitigate potential hazards during assembly, lifting, and operational phases. Implement clear instructions for hoisting operations, key part installations, and site-specific risks pertaining to electrical lines and pipelines.

Guide to Dryer Installation and Debugging

1. Dryer civil foundation base line drawing:

First, bury the center mark and reference point as the basis for equipment installation and subsequent maintenance and alignment. Determine the center datum at both ends, draw the longitudinal centerline of the foundation, draw the transverse centerline of each gear, and the axial centerline of the transmission device. When it appears that some, most, or some of the reserved holes for the foundation have moved too much, you can consider appropriately moving the centerline position within the allowable range to facilitate most of the reserved holes to enter the working position coordinates. The adjusted center point of each gear must be on a longitudinal center line, the transverse center line must be perpendicular to the longitudinal center line, and the longitudinal distance of the transverse center line must be consistent with the measured center distance of each gear.

2. Set up the kiln pad:

Determine the reasonable layout of the pad. Pay attention to that the pad should be as close to the anchor bolts as possible and placed at the center of gravity of the load to prevent uneven stress on the pad. The number of pads in each group should not exceed 5. The thicker pads should be placed up and down, and the thin ones should be placed in the middle. They should be stacked neatly and in good contact with each other. When the adjustment cannot be completely overlapped, the contact area should be greater than 80%.

3. Marking the rotary drying equipment machine base:

Through the optical theodolite, laser collimator or the less accurate wire drawing method, the horizontal leveling and alignment of the supporting wheel base is carried out, and the longitudinal inclination is found several times until the coordinate position, transverse level and longitudinal inclination meet the requirements. Then carry out the overall alignment of the front and rear supporting wheel bases. The longitudinal center lines of the front and rear bases must be on the same line, with a minimum deviation of 0.5mm. The above adjustments can be made with the help of the adjustment bolts at both ends of the base.

4. Assemble the anchor bolts:

After adjusting the exposed length of the bolt, the secondary pouring of the embedded hole can be carried out. When pouring, ensure that the base of the supporting wheel does not allow any displacement or change. Adjust each supporting wheel to the correct position to ensure that the distance between each set of supporting wheels and the longitudinal centerline is equal, the centerline of the supporting wheel shaft is parallel to the longitudinal centerline, and the parallelism error is less than 0.1mm/m.
Adjust the correct position of the wheel blocking device on the rear supporting wheel base so that the axis center line of the blocking wheel coincides with the longitudinal center line. One of the blocking wheels at the discharging end can be in contact with the inclined surface of the wheel belt, and there should be a minimum gap of 10mm between the other blocking wheel and the wheel belt. Assemble the cylinder body and transmission gear.
Adjust the clearance of each coordinated size to an error of less than 0.2mm. Assemble the cylinder and large gear according to the docking marks of the segmented cylinder, and tighten the winching positioning bolts and other connecting bolts. When the cylinder is short, this process can be omitted after the whole assembly is ready before leaving the factory. Lift into position. Make the cylinder device fall smoothly onto the front and rear supporting wheels. If the cylinder is long and heavy and it is difficult to hoist the whole, it can be hoisted in sections according to the actual situation, but detailed measures and required auxiliary supports, tools and other safety measures must be formulated. measure.

5. Install the pinion assembly:

Correct the correct position of the small gear assembly according to the center mark plate, and the error with the transverse center line of the large gear is less than 2mm. Adjust the top clearance of the large and small gears. The tooth top clearance is 0.25 module (standard tooth gap) plus the thermal expansion of the large gear.
Pay attention to the tooth The top clearance is measured and determined at the point where the radial jump of the large gear is maximum. Adjust the contact accuracy of large and small gears. The contact marks on the tooth surface should not be less than 70% along the tooth length and not less than 40% along the tooth height. Note that the direct-coupled transmission does not have a pinion assembly.

6. Install the transmission device:

Based on the pinion, install the reducer, motor and related couplings in sequence. Each transmission axis is parallel to the longitudinal centerline, and the error is less than or equal to 0.05%. When pouring the relevant anchor bolts, it is also necessary to ensure that the transmission components do not allow any displacement or change during the pouring process.

7. Install the inlet and outlet device:

Separately install the front and rear inlet and outlet boxes, and control the peripheral clearance between the inclined flange at the upper seal of the inlet and outlet box and the two ends of the cylinder to be even. When the cylinder rotates, the peripheral gap error is less than 10mm.

Before starting the dryer, ensure compliance with these essential steps:

Only authorized personnel should operate the dryer.
Prior to operation, thorough preparation and inspection are imperative:
Check for any damage to the furnace door, grate, and combustion chamber.
Ensure the air duct is unobstructed and free of leaks.
Verify the blower’s functionality.
Inspect the main bearing cooling canal for smoothness and absence of water leakage.
Confirm the lifting plate is securely in place.
Ensure all parts are intact, and tighten all fastening bolts, anchor bolts, and nuts.
Remove any debris obstructing the dryer’s operation and carefully inspect all moving parts. It’s crucial to keep clear of critical equipment points during operation.

Dryer Operation Protocol: Startup Sequence for the Dryer:

Prior to initiating the dryer, ensure rigorous inspection and adherence to specified guidelines. Only after nearby personnel and transportation equipment have vacated the vicinity, should the signal to start the dryer be dispatched.

Activate the bearing cooling water system.
Ignite the stove.
Initiate the dryer motor.
Engage the dry material conveying and vacuum equipment.
Commence the feeding equipment.
During dryer operation, it is imperative for designated personnel to conduct the following timely inspections:
Verify the tightness of all exposed fixing bolts.
Assess the normalcy of lubrication points for the main bearing, reducer, and motor, checking for overheating in each bearing.
Monitor the smooth operation of the dryer, ensuring absence of abnormal vibrations.
Inspect seals for tightness, checking for leaks such as material, oil, or water.
Evaluate the adequacy of cooling water for the main bearing and reducer.
Assess the normalcy of gear meshing sound from the reducer, noting any unusual strong vibrations.
Monitor motor current values and fluctuations.
Check the contact between supporting wheel and tire belt for normalcy, identifying any abnormal deviations.
Review dryer output and status of drying objects.

Shutdown Protocol for the Dryer:

As the dryer approaches shutdown, preliminary preparations must be executed. Firstly, issue a predetermined signal to alert personnel operating ancillary equipment about the impending shutdown.

Cease material feeding into the furnace and extinguish the fire 30 minutes prior to shutdown.
Halt feeding equipment.
Power down the dryer motor.
Cease operation of conveying and dust collection equipment.
Post shutdown, rotate the cylinder every 10-15 minutes until it cools to prevent bending.
In case of emergency shutdown, aside from immediate fire extinguishing, adhere to the same cylinder rotation procedure until cooldown.

Q: What are common issues and solutions for dryers FAQ?

A: Dryers may encounter various problems during operation. Here are some frequently encountered issues and their solutions:

Shaking or relative movement between the wheel belt and the cylinder body:

Cause: The side of the retaining iron is not clamped.
Solution: Clamp the retaining iron securely and add pads to adjust the gap between the wheel belt, retaining iron, and the cylinder to a recommended gap space which is 41mm.

Damage to meshing between the small gear and the large gear:

Cause: Wear on the small gear.
Solution: Install the small gear in reverse if it’s only worn on one side; replace it if both sides are worn. If the supporting wheel is worn, turn or replace it. For damage between the large ring gear and the cylinder, correct and tighten the connection.

Vibration or up-and-down movement of the cylinder:

Cause: Damage to the connection between the supporting wheel device and the base.
Solution: Correct and tighten the connection between the supporting wheel device and the base. Ensure the supporting wheel is positioned correctly and adjust if necessary.

What to do if the blocking wheel is damaged?

Cause: Excessive axial force on the cylinder.
Solution: Adjust the cylinder to reduce axial force. During normal operation, neither the upper nor lower gear wheels should rotate or rotate alternately.

Rising bearing temperature:

Causes: Lack of lubricating oil, contamination, or excessive adjustment.
Solution: Ensure proper lubrication, clean the bearings, and avoid over-tightening.

What should I do if the lifting plate falls off?

Cause: Broken or worn connecting bolts; worn or rotted support seat.
Solution: Replace connecting bolts promptly and replace worn or rotted support seats.

Reasons for cylinder wear:

Cause: Falling off of the lifting plate, discharge liner, or feed spiral plate.
Solution: Stop the machine promptly if any components fall off and replace them to prevent further cylinder wear.

What are some common daily maintenance tasks for rotary dryers, particularly focusing on the rotary kiln?

Daily maintenance for dryers, specifically rotary kilns, involves several crucial steps to ensure optimal performance and longevity:
Cleaning after dismantling the supporting wheel: It’s essential to clean away any accumulated dirt and metal debris inside the supporting wheel after dismantling it.
Checking for leaks and bolt alignment: Ensure that the supporting wheel device doesn’t leak, and the fixing bolts are vertical. Additionally, confirm that the adjusting screw bottom plate is securely in place.
Positioning the blocking wheel: Consider the contact status of the supporting wheel, wheel belt, and large gear, along with the momentum of the 20mm barrel, when positioning the blocking wheel.
Ensuring concentricity of couplings: The couplings connecting the motor and reducer must be concentric, with a deviation not exceeding 0.03mm.
Checking gear deviations and adjustments: Verify that the outer diameter deviation of the large gear is within 1.5mm, with a swing deviation also within 1.5mm. The adjustment deviation at the “Huff” should be 0.03mm, and it should be securely fixed with pins.
Monitoring tooth thickness and replacement: If the tooth thickness wears down to 50%, it’s necessary to repair or replace it. When replacing the pinion alone, ensure that the corresponding tooth shape is repaired as well.
Consistently performing these maintenance tasks can prevent potential issues and ensure the efficient operation of rotary kilns in dryer systems.

Conclusion:

In conclusion, the installation and operation guide for rotary dryers presented here serves as a comprehensive resource for users seeking efficient and effective usage of this indispensable equipment. By following the step-by-step instructions outlined in this guide, users can ensure a smooth and hassle-free installation process, minimizing downtime and maximizing productivity.

Moreover, the operational tips provided herein offer valuable insights into optimizing the performance of rotary dryers, enhancing their longevity and reliability. From proper maintenance practices to troubleshooting common issues, this guide equips users with the knowledge needed to maintain peak performance levels, ultimately leading to improved outcomes and cost savings.