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PART XVIII BOILERS
|No boiler to be used
18.1 No boiler shall be used unless:
(a) the Chief Inspector has issued a permit for its use.
(b) permission is obtained from the Chief Inspector for boilers that have been out of use for 12 months;
(c) it is constructed in accordance with a code of practice approved by a reputable authority acceptable to the Chief Inspector
(d) it has been manufactured under the supervision of an inspecting authority approved by the Chief Inspector;
(e) it complies with the provisions of these regulation; and
(f) it is maintained in a safe working condition at all times.
Before boilers are erected
18.2 Before any boiler is erected, the mine manager shall submit to the Chief Inspector
(a) the manufacturer's complete specification;
(b) legible, dimensioned drawings of the complete boiler showing details of the plating, riveting and welding;
(c) drawings showing the boiler house, if any, in plan and elevation and the position of the boiler; and
(d) a certificate issued by the inspecting authority incorporating the following information:-
(i) that the authority is satisfied that the boiler is constructed in accordance with the specified code,
(ii) results of the physical and chemical tests carried out on the material used in construction,
(iii) details of the hydraulic test, witnessed by the inspecting authority.
Permits to be issued
18.3 The permit issued in terms of regulation 18.1 shall cease to be valid on transfer of ownership of a boiler or in the case of a stationary boiler when the boiler is moved from the existing site.
18.4 The mine manager shall provide for a boiler inspection register for each boiler in which shall be recorded the result of each inspection and hydraulic test conducted.
18.5 The mine manager shall provide for a log book for each boiler in which shall be entered the dates on which such boiler was cleaned, examined or tested and the condition of the boiler at this examination or test, together with a full report of any alterations or repairs carried out at the time. Each entry in the book shall be made signed by the person who conducted the examination or test or who performed the alteration or repair.
Notification to Chief Inspector
18.6 The mine manager shall notify the Chief Inspector in writing when-
(a) he/she acquires a boiler;
(b) a boiler is damaged;
(c) a boiler is repositioned;
(d) ownership is transferred;
(e) the use of a boiler has permanently ceased;
(f) important repairs and or modifications are to be made to the boiler, such as renewal of any furnace or fixing of any new plate etc. These proposed changes should be accompanied by technical details and drawings.
18.7 Every boiler shall have stamped on it the following information-
(a) name of the manufacturer;
(b) the factory number;
(c) the year of manufacture;
(d) the maximum working gauge pressure in pascals;
(e) the year of first inspection;
(f) the authorized working gauge pressure.
Erection to facilitate safe access
18.8 Every boiler shall be erected in such a manner as to facilitate access to all working areas in an safe and unobstructed manner.
First time commissioning
18.9 Before commissioning a boiler for the first time or after it has been out of commission for more than one year or after major repairs, or modifications, it shall be inspected and tested by a competent person. The results of this inspection and test must be recorded in the boiler inspection register and logbook.
Inspection by Chief Inspector
18.10 The Chief Inspector may inspect and test a boiler upon notification to the mine manager of his/her intention to do so, provided that the mine manager is informed of the date and time of such intended inspection.
Preparation for inspection by Chief Inspector
18.11 The mine manager shall upon receipt of such notification cause all parts of the boiler to be thoroughly cleaned and prepared for inspection and test in accordance with the instructions.
Disposal of workmen and tools for inspection by Chief Inspector
18.12 The mine manager shall place, free of charge, at the disposal of the Chief Inspector, workmen, tools, and any other equipment which may be required for the purpose of carrying out the inspection and test.
Safety precautions of persons during repairs
18.13 When any boiler is being emptied and opened for cleaning, repairs or for any other purpose, every precaution shall be taken to ensure the safety of every person employed on this work or who may be in the vicinity.
Unauthorized entry and interference
18.14 No person shall be permitted to enter any boiler of flue unless the person in charge has satisfied himself that it is safe to do so and that every steam-stop, feed, blow-off, and every other valve or cock which may be a source of danger is blanked off. If any valve or cock cannot be blanked off it shall be closed and fastened securely by means of chain and lock. While the boiler is being cleaned or repaired, no person shall interfere with or open any valve or clock which has been fastened and locked.
Operating voltage of lights
18.15 Where a portable electric lamp is used during cleaning, repair or inspection of any boiler, the operating voltage of such lamp shall not exceed 32 volts.
Usage of water on hot flue, dust or ash
18.16 No water shall be used on hot flue dust or ash where danger may arise therefrom.
Hydraulic test pressure
18.17 The hydraulic test pressure-
(a) for a boiler having an authorized working gauge pressure not exceeding 500 kilo pascals shall be double the authorizing working gauge pressure; and
(b) or a boiler having an authorized working gauge pressure exceeding 500 kilo pascals shall be 1.2 times the authorized working gauge pressure plus 400 kilo pascals.
(c) in every pressure vessel in which the product of the designed working gauge pressure in kilopascals and the capacity in cubic meters exceeds 10, but does not exceed 30, shall be inspected and tested before use.
18.18 Every boiler shall be inspected and tested at least once in each year by a competent person.
Water pressure test
18.19 The test shall consist of a pressure test by water to the pressure prescribed in regulation 18.17
External and internal examination
18.20 The inspection shall consist of a careful examination of the external and internal surfaces of the boiler and all of the fittings and appurtenances.
18.21 When at an inspection any boiler is found to be in a condition from which holds immediate danger, the manager shall order the operation of the boiler to be suspended and the boiler shall not be used until repairs have been conducted to his/her satisfaction.
18.22 No boiler shall be operated at a higher working pressure than authorized.
Level of liquid
18.23 The lowest level of the liquid for any stationary boiler shall be at least 75 millimeters above the highest part of the flues passing round or through the boiler, and for any portable boiler and any boiler of a locomotive, such level shall be of sufficient height above the fire line that even with the oscillation of the boiler the highest part of the surface reached by the fire and heated gases remains covered by liquid.
Liquid level gauges
18.24 Subject to the provisions of regulations 18.27 and 18.31 every boiler shall be fitted with at least two glass liquid level gauges, with proper blow through cocks or valves, for ascertaining the true level of the liquid in the boiler. Where any liquid-gauge cock or valve is not directly attached to the shell of the boiler but to a stand pipe or column, a cock or valve shall be fitted between the boiler and the stand pipe or column if the connecting pipe is of a diameter less than 50millimeters or if it is longer than one meter: Provided that the Chief Inspector may approve of any other reliable means of ascertaining the level of liquid in the boiler.
Connection pipe between pipe and boiler
18.25 Any connecting pipe between the boiler and the stand pipe or column may be of a diameter less than 50 millimeters in any part or may be longer than one meter and may be attached to the boiler without the intervention of a cock or valve provided that the arrangement is otherwise satisfactory and provided further that there is no difficulty in keeping the passage clear and in ascertaining that it is clear. For the latter purpose, the passage in the part of the stand pipe or column between the top and bottom gauge-glass a cock shall be cut off or closed which may be done permanently or by the intervention of a cock in this part.
Blow-through cock or valve discharge
18.26 Every blow-through cock or valve shall be provided with a trail pipe arranged to discharge so that the safety or any person will not be endangered.
Liquid level gauge
18.27 One liquid level gauge shall be sufficient for any boiler with a total capacity of less than 100 liters.
18.28 The fixed liquid level shall be indicated by a conspicuous mark on the liquid level gauge as well as on the boiler shell or masonry.
Liquid level gauge guard
18.29 Every liquid level gauge of the tubular-glass type shall be provided with an efficient guard, which shall not obstruct the reading of the gauge.
Liquid level gauge illumination
18.30 Every liquid level gauge shall be situated and illuminated so that the level of the liquid in the boiler can be readily observed from the operating floor of the boiler at all times.
Liquid level gauge requirements
18.31 Notwithstanding the provisions of regulation 18.24 or 18.27, a liquid level gauge is not required on any fuel or electrically heated boiler where at least two independent means are provided for automatically isolating the source of heat should there be a deficiency of liquid.
Liquid feed supply
18.32 Each boiler which has a total capacity of 100 liters or more shall be provided with at least two reliable apparatuses, each of which shall be capable of adequately supplying the liquid feed requirement of the boiler under all operating conditions, provided that where more than two feeding apparatuses are provided, such feeding apparatuses shall be of sufficient size in the aggregate to supply all the feed requirements should any one such feeding apparatus fail to operate. One of these feeding apparatuses shall be either a power pump or an injector. These feeding apparatuses shall be independent of each other, except that when a separate feed discharge stop valve is fitted to each pump or injector one feed pipe shall be considered to be sufficient. Two or more boilers combined for joint working shall be considered to be one for the purpose of this regulation.
Steam supply separation requirements
18.33 Where the feeding apparatus consists of a steam driven pump, the steam supply to the pump shall be by means of a separate supply pipe from the boiler. Every such steam supply pipe shall be provided with a stop valve as close as practicable to the boiler. Where the source of steam supply to the feeding apparatus can be from more than one boiler, a non-return valve shall be placed adjacent to the stop valve and between the stop valve and the feeding apparatus.
18.34 Every boiler with a total capacity of less than 100 liters shall be provided with at least one feeding apparatus.
18.35 One feed pump shall be considered sufficient for any oil; gas or electrically heated boiler where a means is provided for automatically isolating the source of heat should there be a deficiency of liquid.
One feeding apparatus
18.36 In any boiler in which the product of the authorized working gauge pressure in kilopascals and the evaporative capacity in kilograms per hour, does not exceed 125 000, one feeding apparatus may consist of a hand operated pump, provided that it is of adequate capacity to supply the boiler with liquid.
Separately fired super heater
18.37 The provisions of regulations 18.32 to 18.36 shall not apply to a separately fired super heater.
Delivery feed pipe
18.38 The point where the delivery feed pipe enters the boiler shall be provided with a self-acting non-return valve and a stop cock or a wheel valve. The stop cock or wheel valve shall be placed between the non-return valve and the boiler. Where the feed delivery pipes are duplicated and provided with inter-connecting valve arrangement, the Chief Inspector may permit the use of a combined stop and non-return valve on each feed pipe.
Feed supply through economizer
18.39 Where the feed supply to any boiler is through an economizer which is not an integral part of the boiler-
(a) the economizer flue shall be fitted with a damper and a by-pass flue, and
(b) an alternative direct feed from the feeding apparatus shall be provided to the boiler.
18.40 Every boiler, other than an economizer and a separately-fired superheater, shall be provided with a contrivance by which the deficiency of liquid is made known automatically and independently of any personal observation. The contrivance may be either a whistle operated by a float or other means.
Low liquid alarm
18.41 Notwithstanding the provisions of regulation18.40,every fuel or electrically heated boiler shall either have a low liquid alarm other than a fusible plug or be provided with a means for automatically isolating the source of heat should there be a deficiency of liquid.
18.42 Subject to the provisions of regulation 18.43, every boiler shall be provided with at least two reliable safety valves. Each valve shall be loaded so that it will open at or below the authorized working gauge pressure. The aggregate area of the opening of the valves for the discharge of steam, vapour or gas shall be sufficient to prevent the pressure rising in excess of 10 per cent above the authorized working gauge pressure, should any one of the safety valves fail to open.
Safety valve installation
18.43 Every safety valve shall be attached as close as possible to the main steam, vapour or gas space of the boiler without any intervening stop valve.
Safety valve to be locked
18.44 At least one of the safety valves shall be locked and shall be accessible only to the person in control. The locked valve or valves shall have an area not less than and shall open at a pressure not greater than any valve not locked.
Access to safety valve
18.45 One safety valve, which shall be locked and which shall accessible only to the person in control, shall be sufficient-
(a) for any boiler with a total capacity of less than 100 liters,
(b) for any economizer and any separately-fired superheater which can be shut off from the boiler, and
(c) for any oil, gas or electrically heated boiler where a means is provided for automatically isolating the source of heat should the pressure rise above that at which the safety is loaded to open.
Authorized working gauge pressure
18.46 No undue weight shall be placed on a safety valve of any boiler nor shall the load on any safety valve be increased in a way which will prevent the safety value opening at the authorized working gauge pressure.
Safety valve construction
18.47 Every safety valve shall be constructed so that the valve can be freed easily from its seat at any time and provision shall be made to prevent the valve from flying off should the spring or lever break or should the load on the valve be removed suddenly by accident or other cause.
Safety valve load
18.48 Every safety valve loaded by a weight or spring acting on a lever shall be constructed so that the load acts only upon the extreme end of the lever and such load shall be secured to the lever. Where a safety valve is loaded directly by a spring, every compression adjusting screw shall abut against a metal stop or washer when the spring is at the working-load compression.
Main stop valve
18.49 Every boiler shall be provided with a main stop valve at the discharge outlet and as close as practicable to the boiler.
Non return valve between boilers
18.50 If more than one boiler is connected to a common main, a self-acting non-return valve shall be placed between each boiler and the common main.
Auxilliary apparatus feed through main stop valve
18.51 Steam, vapour or gas required for any purpose other than for the operation of the boiler auxilliary apparatus shall be drawn only through the main stop valve.
Safety valves, component parts and connections
18.52 Every safety valve and every valve at any discharge outlet, its component parts and its connection to the boiler shall be constructed of metal; Provided that cast iron shall not be approved for any such valve, its component parts and its connection to a boiler which has an authorized working gauge pressure exceeding 1 megapascal.
Blow-off cocks or valves
18.53 Every boiler shall be provided with at least one blow-off cock or valve connected by a flange direct or by means or a flanged pipe to its lowest point.
Blow-off cocks or valves requirements
18.54 Every blow-off cock or valve, its component parts and its connection to the boiler shall be constructed of a metal, other than cast iron.
Connecting pipe requirements
18.55 Where any connecting pipe is fitted between the blow-off cock or valve and the boiler, the pipe shall not be in contact with any masonry; it shall be joined by flanges, and if the flange is not solid with the pipe or welded to the pipe, the pipe shall pass through the flange and be riveted over on the inside in addition to any other connection between the flange and the pipe, such as screw threads or rivets; where the authorized working gauge pressure is in excess of 3 megapascals, every flange shall be welded on and the welding shall be stress-relieved.
Operating keys to be removed
18.56 Every key for operating a blow-off cock or valve shall be removed when the blow-off cock or valve is fully closed.
Blow-off cock or valve discharge
18.57 The discharge from blow-off cock or valve of two or more boilers shall not lead into a common pipe except with the written permission of the Chief Inspector.
18.58 The discharge from every blow-off cock or valve shall be conducted by means of a pipe into an open or suitably vented tank, drain or sump, which is situated and guarded so as to prevent danger to any person. The blow-down pipe shall be graded so that the liquid will flow freely to the tank.
Reliable pressure gauge
18.59 Every boiler shall be provided with at least one reliable pressure gauge which shall be connected to that part or the boiler where the highest vapour pressure occurs. The dial of the gauge shall be graduated to show pressure in terms of pascals and the maximum pressure which the gauge shall be capable of registering shall not be less than the hydraulic test pressure as defined in regulation 18.17 and not more than double the authorized working gauge pressure. The authorized working gauge pressure shall be clearly marked with a red line on the dial of the gauge. The gauge shall be situated and the dial illuminated so that the working pressure can be read distinctly from the operating floor or the boiler at all times.
Pressure gauge requirements
18.60 Every pressure gauge shall have a separate direct connection with the boiler. Where a pressure gauge is attached to the shell or drum of the boiler the connection shall be by means of a U-pipe or equivalent device of sufficient capacity to keep the gauge tube filled with liquid. The pressure gauge shall be capable of being shut off for the boiler and the cock or valve used for this purpose shall be in full view.
Authorized working gauge pressure
18.61 When the authorized working gauge pressure of any boiler is 2,8 megapascals or less there shall be provided a contrivance consisting of a cock with a flange 40 millimeters in diameter by five millimeters thick for the attachment of the test pressure gauge.
Contrivance to be provided
18.62 Where the authorized working pressure of any boiler is in excess of 2,8 megapascals there shall be provided a contrivance consisting of a valve or cock carrying in a vertical position a receiving socket for the attachment of the test pressure gauge. The receiving socket shall be tapped with a 10-millimeter B.S. thread and shall be fitted with an easily removable screw plug.
18.63 The contrivances required in terms of regulations 18.60 and 18.61 shall be situated so that the test gauge and the boiler gauge can be read from the same place.
18.64 Every boiler shall be provided where necessary with sufficient and suitable inspection openings situated so that all the internal surfaces and seams may be readily cleaned and inspected.
Provision of manholes
18.65 Every boiler where the dimensions permit entry shall be provided with at least one manhole of not less than 400 millimeters by 300 millimeters for an elliptical hole and not less than 400 millimeters in diameter for a circular hole, provided that where a boiler is fitted with a removable end or cover plate which is of sufficient size to permit entry, the boiler shall be deemed to comply with the provisions of this regulation.