The distribution company shall design an elaborate work permit format for the maintenance work which shall be used by the service provider for carrying out any maintenance work. It shall be the responsibility of the service provider to make necessary inspection in line with the work permit before commencement of the work.
The user shall get the inspection of the cylinder manifold, distribution piping, safety system, equipment, valves fittings, auto change over system, gas monitoring system, hydrant hoses, etc, regularly as per the periodicity defined by the Distributing Company. However, minimum periodicity of inspection shall be once a year and the records have to be maintained. The inspection shall include checking the health, performance of all equipment like valves, PRV, auto changeover system for proper operation (wherever installed), underground piping, etc. Work permit system developed by the LPG distribution company shall be followed.
The repair, maintenance of any defective piping, manifold or any other equipment has to be carried out by agencies approved by the LPG distribution company or distributing company itself.
Pneumatic testing and hydro testing of piping shall be done once in five years by agencies approved by distribution company.
Maintenance – regularly
The strainer provided on the manifold should be cleaned at least once in a month.
Vaporiser shall be checked as per maintenance schedule.
The burners shall be regularly cleaned.
Pigtails shall be checked every time empty cylinder is replaced by a filled cylinder and replaced in case of any physical damage.
Maintenance – once in six months
All the manifold installations shall be checked once in six months by the authorized agency or the LPG distributing company and record to be maintained at the installation location.
The earthing resistance shall be checked twice a year once during the summer season and once during winter and records for same shall be maintained.
The hoses (used in liquid off take valve multi cylinder installation) shall be hydro tested at 25 kg/cm2 pressure once in six months.
Maintenance – once in a year
Part of the Installation working at cylinder pressure to be tested at 25 kgf/cm2 or 1.5 times the developed pressure at 65°C, whichever is more, once in a year.
Downstream part of the installation after PRV to be tested at one and a half times the maximum outlet pressure that may be given by an adjustable PRV or 2 kgf/cm2, whichever is more, once in a year.
Portions of installation not subjected to cylinder pressure but carrying gas at pressure more than 30 gf/cm2 to be tested at 2.5 times the working pressure for 2 min, once in a year.
Portions of installation subjected to gas pressure of 30 gf/cm2 or less, to be tested at 2.5 times the working pressure for 2 min, once in a year.
Note: The standard recommends conducting a pressure test for a duration of 2 minute. However, we believe this may be a typographical error. Given the critical safety implications of pressure testing, a duration of 2 hours would be more appropriate and aligns with standard industry practices.
Piping and manifold should be checked once a year visually for corrosion, any physical damage. All supports of manifold should also be checked for any corrosion, etc.
The manifold should be internally cleaned once a year and should be free from contaminants.
The pressure gauges should be calibrated once in a year and proper records should be maintained. The dial of the gauge should be clearly visible.
The PRV should be checked once in a year for correct settings and performance as well as for corrosion and mechanical damage. All PRV shall be throttled once a year for its accurate throttled pressure and safe operation.
Hydro test of pigtails and flexible LPG hoses (used in vapour off take valve multi cylinder installation) shall be carried out on yearly basis.
All the safety valves, TRV shall be checked once a year.
All the other valves should be checked once a year for free and full range of movement, positive shut off, mechanical damage, etc.