headerdrawing1.jpg (96365 bytes)

Sulphuric Acid on the WebTM Technical Manual DKL Engineering, Inc.

Knowledge for the Sulphuric Acid Industry Line.jpg (1139 bytes)

Sulphuric Acid on the Web

Introduction
General
Equipment Suppliers
Contractor

Instrumentation
Industry News
Maintenance
Acid Traders
Organizations
Fabricators
Conferences

Used Plants
Intellectual Propoerty
Acid Plant Database
Market Information
Library

Technical Manual

Introduction
General

Definitions
Instrumentation
Plant Safety
Metallurgial Processes
Metallurgical
Sulphur Burning
Acid Regeneration
Lead Chamber
Technology
Gas Cleaning
Contact
Strong Acid
Acid Storage
Loading/Unloading

Transportation
Sulphur Systems
Liquid SO2
Boiler Feed Water
Steam Systems

Cooling Water
Effluent Treatment
Utilities
Construction
Maintenance
Inspection
Analytical Procedures
Materials of Construction
Corrosion
Properties
Vendor Data

DKL Engineering, Inc.

Handbook of Sulphuric Acid Manufacturing
Order Form
Preface
Contents
Feedback

Sulphuric Acid Decolourization
Order Form
Preface
Table of Contents

Process Engineering Data Sheets - PEDS
Order Form
Table of Contents

Introduction

Bibliography of Sulphuric Acid Technology
Order Form

Preface
Contents

Sulphuric Acid Plant Specifications
 

Google Search new2.gif (111 bytes)

 

 


Maintenance and Inspection - Cooling Towers
September 10, 2003

Introduction
Maintenance and Inspection Schedule
Inspection Checklist
Associated Links

Cooling Towers


Introduction

The following inspection checklist provides a general guide of what to look for when performing a cooling tower inspection.  The checklist is general in nature so some of the points may not apply to your particular installation.

The results from a thorough cooling tower inspection will enable the plant to properly plan repairs and maintenance.  A properly maintained cooling tower will provide trouble free and reliable operation.

Maintenance and Inspection Schedule

Daily
  • Check operation of cooling water pumps for excessive noise, vibration, etc.
Weekly
  • Inspect trash screen and remove accumulated debris
Shutdown
  • Perform a detailed inspection of system.

Inspection Checklist

Tower Casing
  • Check for leaks, holes, cracks or general deterioration in the structure.
  • Make sure access doors are in good working condition and that doors shut tightly when tower is in operation.
  • Check steel casing for corrosion or scale build-up.
  • Check wood casing for signs of decay, soft rot or plywood delamination.
  • Check Fiberglass for evidence of brittleness or cracking.
Structure
  • Steel Structures
    Inspect steel structures for corrosion, particularly loss of metal. 
    Spot check the tightness of bolted joints. 
    Check for corrosion near welded joints on galvanized steel towers.
  • Wood Structures
    Inspect wood structures for wood decay, cracks, fractures and rot in wood members.  
    Perform both visually and by tapping with a hammer.  A dull, low-pitch sound indicates softness, while a higher pitch sharp sound indicates sound wood.  Probe soft spots with a sharp object to determine the extent of the damage.  Pay particular attention to the wood around fasteners as well as the bottom of columns.
  • Fiberglass or Plastic Structures
    Inspect fiberglass or plastic structures lloking for evidence of tearing of cracking.  Spot check the tightness of bolted joints.
Fan Deck
  • Check the general condition of the fan deck material looking for leaks, holes, cracks or general deterioration in the structure.
  • Check for the presence of tripping hazards.
Cooling Tower Access
  • Stairs
    Check for evidence of wood decay or steel corrosion.
    Check for loose treads, handrails or stringers.  
    Check that all hardware is in good condition and tight.
  • Ladders
    Check the general condition of the material.
    Check that all hardware is in good condition and all connections between the tower and ladder are secure.
  • Walkways
    Check the general condition of the material.
    Check for loose treads or handrails.
    Check that all hardware is in good condition and tight.
    Particular attention should be paid to any damage or deterioration that may pose a potential hazard to personnel.
Cold Water Basin
  • Check for excessive build-up of sludge or debris.  Clean as required.
  • Check condition of sump, sump screen.  Clean as required.
  • Check the general condition of the basin material.
  • Check for any signs of leaks or breakdown of sealing material.
Distribution Basins
  • Check the general condition of the material.
  • Check for leaks.
  • Check that all hardware is in good condition and tight.
Piping
  • Examine all supports.
  • Check for leaks at all connections.
  • Check the general condition of all piping looking for signs of corrosion or deterioration.
Spray Nozzles
  • Check for missing or damage.
  • Check for clogged or blocked nozzles.
  • Check that all nozzle components are in place and working properly (i.e. splash plates).
Tower Fill
  • Splash Fill
    Check the condition of the splash bars.  Check for sagging, broken, missing, heavily-scaled pieces.
    Check the support grids.
    Check the support members for deterioration and damage.
  • Film Fill
    Check for build-up of scale, algae or other contaminants on the surface of the fill.
    Check for damaged sheets or sections.
    Check the support members for deterioration and damage.
Drift Eliminators
  • Check for cleanliness and that all air passages are clear.
  • Check the condition of the seals to assure that water can't bypass the drift eliminators.
Louvers
  • Make sure all louvers are in place.
  • Check for excessive scale build-up or biological growth.
  • Check the condition of the support members.
Mechanical Systems
  • Gear Boxes
    Check the oil level and condition.  Drain off a small sample and check it for water, metal shavings or sludge.  Add or replace the oil as required.
    Check for oil leaks and replace seals as required.
    Check the backlash and endplay in the gear and record values for future reference.
    Check the mounting of the gear box to ensure it is tight and in good condition.
  • Couplings and Drive Shafts
    Check the coupling alignment.
    Check the mid-span bearing (if so equipped) and lubricate are specified in manufacturer's instructions.
    Check the drive shaft for corrosion or damage.
  • Belt Drives
    Check the condition of the pulleys noting any corrosion or loss of metal.
    Check for proper belt tension and alignment.
    Check the condition of the belts.  If the belt shows signs of wear, gouges or cracks they should be replaced.
    Check the fan shaft bearings for proper lubrication, tightness and that the seals are in good condition.
    Check the support structure for corrosion or damage.
Fans
  • Check fan blades for corrosion or erosion.
  • Check for excessive build-up of deposits.
  • Check the connection between the blades and the hub.
  • On fans with variable-pitch blades, carefully measure the pitch angle of each blade and re-adjust to the manufacturer's recommendations if required.
  • Operate the fan and check for excessive vibration that may indicate an out of balance condition.
Fan Stacks
  • Check the condition of the material.
  • Check that all hardware is in good condition and tight.
  • Check for leaks or holes.
  • Measure the fan blades tip clearance all around the stack using the longest fan blade.  Adjust tip clearance as per the manufacturer's instructions if required.

The condition of the cooling tower is important not only from the performance point of view but also from a health point of view.  Cooling towers are ideal breeding grounds for water born bacterial, such as Legionella bacteria.  Cleanliness of all parts of the tower will minimize the chance of these bacteria growing in the cooling water system