Maintenance Of Surveying Instruments In Kenya
Surveying equipment is used under most stressful conditions. The equipment is exposed to extreme weather conditions, used in dusty construction areas and is subject to bumpy transportation. Proper care in the method by which equipment is used, stored, transported, and adjusted is a major factor in the successful completion of the survey. Lack of good maintenance practices not only causes unjustified replacement costs, but also can seriously
affect the efficiency and accuracy of the entire survey.
Surveying instruments, which include theodolites, levels, total stations, electronic measuring devices, and GPS receivers, are designed and constructed to provide years of reliable use. The shafts, spindles, pendulums, and electronics of precision instruments, although constructed for rugged field conditions, can be damaged by one careless act, negligence or continued negation prescribed procedures for use, care, and adjustment of the instrument.
The following general principles of care and servicing should be applied as a routine matter
for all survey equipment and supplies.
- All equipment and tools should be kept as clean and dry as practicable, particularly if they are to be transported or stored for any length of time.
- Wooden surfaces should be wiped clean of caked mud or moisture prior to returning the equipment to the vehicle. The original painted or varnished surfaces should be repaired as often as needed to keep moisture from entering the wood.
- Metal surfaces should be cleaned and wiped as dry as practicable. A coat of light oil should be applied to tapes and the metal parts of tools to prevent rusting during storage. Excess oil should be wiped off
Routine Care of Surveying Instruments
Before making the first set up of the day, visually inspect the instrument for cracks, bumps, and dents. Check the machined surfaces and the polished faces of the lenses and mirrors. Try the clamps and motions for smooth operation (absence of binding or gritty sound).
- Frequently clean the instrument externally. Any accumulation of dirt and dust can scratch the machined or polished surfaces and cause friction or sticking in the motions.
Dirt and dust should be removed only with a clean soft cloth or with a camel hair brush.
Non-optical parts may be cleaned with a soft cloth or clean chamois.
Clean the external surfaces of lenses with a fine lens brush and, if necessary, use a dry lens tissue. Do not use silicone treated tissues, as they can damage the coated optics. It is permissible to breathe on the lens before wiping it, but liquids, such as oil, benzene, water, etc., should never be used for cleaning purposes. DO NOT loosen or attempt to clean the internal surfaces of any lens.
Cover an instrument whenever it is uncased and not being used for any length of time, particularly if there is dust or moisture in the air.
After an instrument has been used in damp or extremely cold situations, special precautions must be taken to prevent condensation of moisture inside of the instrument. When working with the instrument in cold weather, it should be left in the carrying case in the vehicle overnight. If stored in a heated room overnight, the instrument must be removed from the carrying case. If the instrument is wet or frost covered, remove it from its case, and leave it at room temperature to dry out.