65. [ Safety measures for pressure plant and vessels operated under pressure over atmospheric pressure. [Substituted by G.N. dated 28.5.1982 published in M.G.G. Part I-L p.5939]
(1)In this rule,-(a)'competent person' means person who is, in the opinion of the Chief Inspector capable by virtue of his qualifications, training and experience of conducting a thorough examination and pressure tests, as required, on a pressure vessel or plant and of making a full report on its condition;(b)'maker' means any person in whose name the pressure plant or pressure vessel is either manufactured under a patent or sold;(c)'pressure plants' means the pressure vessel along with its pipings and other fittings operated at a pressure greater than the atmospheric pressure;(d)'pressure vessel' means any vessel subjected to or operated at a pressure greater than the atmospheric pressure.(2)Every pressure plant or pressure vessel used in any factory shall be-(a)properly designed on sound engineering practice;(b)of sound construction and material and of adequate strength and shall be free from any defect; and(c)properly maintained in a safe working condition:Provided that where there is an Indian Standard or a standard of the country of manufacture in respect of any pressure plant or pressure vessel or where the design or construction of any such pressure plant or pressure vessel has been regulated by any other law or regulation in force, it shall be designed and constructed in accordance with the said standard, law or regulation, as the case may be, and a certificate thereof shall be obtained from the maker or from competent person.(3)(i)Every pressure plant or pressure vessel shall be fitted with-(a)a suitable safety valve or other effective device, conveniently located to ensure that the maximum safe working pressure of the vessel shall not be exceeded at any time;(b)a suitable pressure gauge with a dial range not less than 1.5 times and not exceeding twice the maximum safe working pressure, easily visible and designed to show, at all times, the correct internal pressure in kilograms per square centimetre and marked with prominent red mark at the maximum safe working pressure of the pressure plant or pressure vessel;(c)a suitable stop valve or valves by which the pressure vessel or the system of pressure vessels may be isolated from other vessels or source of supply of pressure;(d)a suitable nipple and globe valve connected for the exclusive purpose of attaching a test pressure gauge for checking the accuracy of the pressure gauge referred to in clause (b) of the sub-rule;(e)a suitable drain cock or valve or a plug at the lowest part of a pressure vessel so as to ensure effective draining of liquid that may be collected in the pressure vessel.(ii)Every pressure gauge, stop valve, nipple and globe valve, shall be mounted at a height not more than 1.5 metres from the working level.(iii)Every pressure plant or pressure vessel not constructed to withstand the maximum possible working pressure at the source of supply or the maximum pressure which can be obtained in the pipe connecting the pressure vessel with any other source of supply shall be fitted with a suitable reducing valve or other suitable automatic device to prevent the safe working pressure of the vessel being exceeded. Suitable pressure guages shall be provided close to the reducing valve to show the high pressure and reduced pressure.(iv)In case of a jacketted vessel in which heat is transmitted by means of steam or other media in the jacket causing pressure rise in the vessel, the heat input in the jacket shall be so controlled by a suitable device as not to allow the safe working pressure of the vessel being exceeded.(v)To further protect the pressure vessel in the event of failure of reducing valve or the control device mentioned in clauses (iii) and (iv) an additional safety valve having a capacity to release all steam, vapour or gas without under pressure rise shall be provided in addition to the one referred to in clause (1)(a).Provided that it shall be sufficient for the purposes of this sub- rule if the safety valve, pressure guage and stop valve or other suitable effective device are mounted on a pipeline immediately adjacent to the pressure vessel and where there is a range of two or similar pressure vessels in a plant served by the same pressure load, only one set of such mountings need be fitted provided that those cannot be isolated from any of the pressure plant or pressure vessels.(4)Ever pressure plant in service shall be thoroughly examined by a competent person,-(a)externally once in every period of six months;(b)internally, once in every period of twelve months, and(c)hydraulic test once in a period of four years.Explanation. - If however by reason of construction of the pressure vessel or pressure plant a thorough internal examination is not possible, it may be replaced by a hydraulic test, which shall be carried out once in every period of two years:Provided that in the case of pressure vessel or pressure plant with thin walls such as sizing cylinders made of copper or any other non-ferrous metal, periodic hydraulic test may be dispensed with if the requirements laid down in clause (5) are complied with:Provided further that if the Chief Inspector or any Inspector authorised by him certifies that it is impracticable to carry out a thorough external or internal examination of any pressure vessel or pressure plant as required by clauses (a) and (b) and if owing to its constructions and use a hydraulic test as required by this sub-rule cannot be carried out, a thorough external examination shall be carried out at least once in every two years and a thorough systematic non-destructive test like ultrasonic test, for metal thickness or other defects of all parts shall be carried out at least once in every period of four years.(5)(a)(i)As far as possible, in respect of every sizing cylinder the shell whereof is made of copper sheet or any other non- ferrous metal and which is put to use before the 31st October, 1963 the Manager shall make available to the Inspector and the competent person examining such cylinder, information about the date on which such cylinder was put to use for the first time with full particulars as to the thickness of the shell when so taken into use in the factory for the first time. Information shall also be made available about the working pressure recommended by the makers when the cylinder was put to use for the first time in the factory.(ii)If no such information is available, any other evidence relevant to show the age of the cylinder shall be submitted by the Manager to the Chief Inspector. The Chief Inspector shall determine the age of the cylinder on such documentary evidence or other oral evidence that may be presented to him by the Manager or any other evidence that may be produced, and the age so determined shall be considered as the age of cylinder for the purpose of this rule.(b)(i)The minimum thickness of the shell of a sizing cylinder shall be actually measured once in a period of two years.(ii)If during its working life, the shell of a sizing cylinder is at any time punctured requiring repairs to the cylinder to close the punctured portion, the thickness of the sheet of the shell near such puncture or opening shall be measured by a competent person.(c)(i)No sizing cylinder shall be subjected to work at a pressure greater than the maximum safe working pressure recommended by the makers of such cylinder at the time when such cylinder was first put to use in a factory.(ii)No sizing cylinder which has been in use for more than five years shall be subjected to work at a pressure greater than the lowest of the most safe working pressure calculated in accordance with the following three methods, namely:-(a)Same proportion to the original safe working pressure when first put to use as the minimum thickness of the shell materials as actually measured at any time bears to the original thickness of the shell material when first put to use;(b)Calculated on the basis of the minimum thickness actually measured so that the tensile stress in the shell shall not exceed safe working stress for the material of the shell;Explanation. - If the shell is made of copper, safe working tensile stress shall be taken to be not more than 350 kilograms per square centimetre.(c)Reduced at the rate of 4 per cent of the original working pressure for every year of its use after the first five years;(d)No sizing cylinder shall be continued to be used for more than twenty-five years after it was first put to use:Provided that the Chief Inspector may authorise the use of sizing cylinders beyond the period of twenty-five years for a period not exceeding five years, if tests are carried out and further details are made available to his satisfaction to indicate that the cylinder can be used with safety.(6)(i)The maximum safe working pressure and the date of the last examination shall be plainly marked on every pressure vessel or pressure plant and no pressure plant or pressure vessel shall be operated or used at a pressure higher than the maximum safe working pressure.(ii)No pressure plant or pressure vessel which has been previously used or has remained isolated or idle for a period exceeding 6 months or which has undergone repairs or alternations shall be used in a factory unless it is examined and tested by a competent person.(iii)No pressure vessel or pressure plant shall be taken into use for the first time in any factory unless-(a)a certificate specifying the maximum safe working pressure and the tests to which it was subjected to, is obtained from the maker; and(b)it is thoroughly examined by a competent person in the premises where it is used;(c)if during any examination, any doubt arises as to the ability of the pressure vessel or plant to work safely until the next prescribed examination, the competent person shall enter in the prescribed Form, his observations, findings and conclusions with reasons therefor and other relevant remarks and may authorise the pressure vessel or pressure plant to be used and kept in operation, subject to a lowering of maximum safe working pressure, or to more frequent or special examination or test or subject to both of these conditions.(d)where the report of any examination under this rule specifies any conditions and suggestions for the working of a pressure plant or pressure vessel the same shall not be used except in accordance with those conditions and suggestions.
