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इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru “The Right to Information, The Right to Live” “Step Out From the Old to the New” IS 3832 (2005): Hand-Operated Chain Pulley Blocks [MED 14: Cranes, Lifting Chains and Related Equipment] “!ान $ एक न’ भारत का +नम-ण” Satyanarayan Gangaram Pitroda ““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee”” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै” Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” IS 3832:2005 w?mm mm n av@kii% – @!awlfdd ( dk7 @i!wl ) Indian Standard HAND-OPERATED CHAIN PULLEY BLOCK — SPECIFICATION (Third Revision) ICS 53.020.30 0 BIS 2005 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI 110002 April 2005 Price Group 6 .. .. . ‘Cranes, Lifting Chains and Its Related Equipment Sectional Committee, ME 14 FOREWORD This Indian Standard (Third Revision) was adopted by the Bureau of Indian Standards, after the draft finalized by the Cranes, Lifting Cha@s and Its Related Equipment Sectional Committee had been approved by the Mechanical Engineering Division Council. Hand-operated chain pulley blocks are used extensively for material handling during construction, erection and maintenance of industrial plants. This standard was revised in 1971 and in 1986. In the second revision, the minimum requirements of onload chains were upgraded to Grade 40. Further a design with factor of safety of 4 was added. In this revision, additions have been made to the following: a) Introduction of aclassification systembroadly based on 1S0 4301-1 : 1986‘Cranes and lifting appliances — Classification — Part 1:General’, and b) Introduction of number of light load test and endurance type test. Assistance also has been taken from BS 3243:1990 ‘Hand-operated chain blocks’. .- This standard covers mechanical aspects related to design, manufacture, erection and testing of the jib cranes required for the shop floor and general workshop applications like pillar, wall bracket jib cranes. including moving cantilever wall cranes. This standard has been prepared based on indigenous manufacturers datrdpractices prevalent in the field in India. The composition of the Committee responsible for formulation of this standard isgiven inAmex D. For the purpose of deciding whether aparticular requirements of this standard iscomplied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS2:1960 ‘Rules for rounding off numerical values (revised)’. Thenumber of significant places retained inthe rounded off value should be the same asthat of the specified value inthis standard. IS 3832:2005 Indian Standard HAND-OPERATED CHAIN PULLEY BLOCK — SPECIFICATION ( Third Revision) 1SCOPE [S No. Title 5669:1987 General plan of boundary This standard lays down the general requirements and dimensions for radial rolling testing ofthehand-operated chainpulleyblocks,worm bearings (fh-st revision) or spur gear type. 6216:1982 Short link chain, grade T (8) 2 REFERENCES calibrated forpulley block and other lifting appliances (first revision) The following standards contain provisions which through reference inthis text, constitute provisions of 6547:1972 Specification for electric chain this standard. At the time of publication the editions hoists indicated were valid. All standards are subject to 7460:1988 Tolerances for tapered roller revision, and parties to agreements based on this bearings @rst revision) standard are encouraged to investigate the possibility 7461 General plan of boundary of applying the most recent editions of the standards dimensions for tapered roller indicated below: bearings: IS No. Title (Part 1): 1993 Single row bearings (second 210:1993 Grey iron castings — Specification revision) ~ourth revision) (Part 2): 1992 Double row bearings (second 305:1981 Specification for aluminium bronze revision) ingots and castings (second (Part 3): 1992 Flanged cups (second revision) revision) 8500:1991 Structural steel — Micro alloyed 617:1994 Aluminium and aluminium alloy (medium andhigh strength qualities) ingots and castings for general — Specification (first revision) engineering purposes (third revision) 14329:1995 Malleable iron castings 1030: 1988 Carbon steel castings for general 15560:2005 Point hook with shank up to 160 engineering purpo ses (fifthrevision) Tonnes — Specification 1875:1992 Carbon steel billets, blooms, slabs 3 TERMINOLOGY and bars for forgings (first revision) For the purpose of this standard, the following definitions shall apply (see Fig. 1). 2062:1999 Steelforgeneral structural purposes — Specification (fifth revision) 3.1 Hand-Operated Chain Pulley Blocks —Ablock 2429 (part 1): Specification for round steel short reevedwith aloadchain and operated byahand chain 1987 link chains (Electric butt welded), soasto give a mechanical advantage. grade L(3): Part 1Non-calibrated 3.2 Working Load Limit — The maximum mass loadchainforliftingpurposes (third which the block shall be designed to raise, lower or revision) suspend in general service. 3109 (Part 2) : Specification for short link chain, 1982 grade M (4): Part 2 calibrated load 3.3 Safe Working Load — The maximum mass, chain for pulley blocks and other which the block shall raise, lower or suspend in a lifting appliances (second particular servicecondition. Itshallnotbegreater than revision) the working load limit but itmay be less. 4215:1983 Specification for ring type needle 3.4 Range of Lifting — The distance between the bearings (first revision) upper and lower limits of travel of the load hook. 4367: 1991 Alloy steel forgings for general 3.5Velocity Ratio —Theratiobetween the velocities industrial use (first revision) of hand chain and the load. It is equal to the number IS 3832:2005 LOAD CHAIN WHEEL T HAND CHAIN TOP HOOK WHEEL ~ \ f SUSPENSION LE 4 LOAD CHAIN SLACK END ANCHORAGE ‘ilLEE1 HAND CHAIN i BOTTOM BLOCK I ~ I WITH SWIVEL i : ,,- . . HOOK L i LOAD CHAINZ !! f! ~$ I I r“ ‘7 \., / t v /“ ~BOTTOM BLOCK IN EXTENDED POSITION FIG.1 CHAINPULLEY BLOCK 2 IS 3832:2005 of metres the hand chain has to be moved to raise or times the working load limit. It shall take into lower the hook through a distance of one meter. account of the state of loading and expected life (see Annex A) and shall be based on the information 3.6 Factor ofSafety —Theratiobetweentheultimate providedbythepurchaserinaccordancewithAnnex B. strength ofthepulley block asaunitandworking load limit where the ultimate strength of the pulley block 4.2 Classification is the minimum load on the load hook under which 4.2.1 Hoists shall be classified in four classes with the load chain or any other component of the pulley respect to the frequency of application and variation block gives away. of magnitude of the load (see 4.2.3) and the effect of 3.7Chain Pull or Operating Effort —Averageeffort, impact. inNewton, exerted bythe operator onthehand chain 4.2.2 The materials used in the construction of to lift the load to working load limit and keep it in hoists shall be properly selected for the stresses motion. encountered whentheequipment isusedinaccordance 3.8 Suspension Level — The level of the suspended withthemanufacturers’ recommendations. Thedesign hook bedinthecaseofablock suspended 170mahook. of the component parts of the hoist shall include In the case of a block combined with a trolley, the due allowance for the effects of the duty which level of the surface upon which the trolley runs. the mechanism will perform in service and shall be in accordance with the requirements of 4.2.3 3.9 Head Room — The distance between suspension and 4.2.4. level and the saddle of the load hook in its highest position, without causing any undue tension on load 4.2.3 Design on Strength Basis chain litling anchorage. Inthe design of acomponent on the basis of ultimate 3.10 Extended Dimension — The distance between strength, the value of stress factor multiplied by the suspension level and the bottom hook saddle, when duty factor forthe appropriate hoist class;where basic the bottom hook is in the lowest operating position, stressfactor shallbenot lessthan 5andthe duty factor without causing anyundue tension onloadchain slack shall be as given in Table 1for the appropriate hoist endanchorage. Itequals the sumofthe headroom and Class 1and Class 2. range of lifting. 4.2.4 Design on Life Basis 3.11 Operating Level — The level on which the Components designed onthe basis of life shall have a operator stands. rated life of not less than 20 years of 250 days per 3.12 Competent Person — The person who is year for Class 1,300 days per year for Class 2, and approved and declared as such under the relevant 333 days per year for Class 3 and Class 4. statutory provisions. 4.2.4.1 The running hours per day orthe life, inhours 4 DESIGN AND CLASSIFICATION used for the purpose ofthe design of the components shallbethe value specified value specified in Table 1 4.1 Design for the appropriate class. 4.1.1 The blocks shall be so designed that all 4.3 Selection of Safe Working Load components shall withstand without failure, an application tothe block ofaloadequal to atleastfour The safeworking load shallbeselected inaccordance Table 1Duty Factor and Life of Mechanism (Clause 4.2.3) S1No. Mechanism Class Duty Factor Average Life A \ f h ~Strength Wear Running TotalLife h/day h (1) (2) (3) (4) (5) (6) i) 1 1.0 0.4 0.5 Over2500 ii) 2 1.0 0.5 1.5 Over9000 iii) 3 1.2 0.6 3 Over20000 iv) 4 1.4 0.7 Over6 Over40000 3 ,.. IS 3832:2005 with Table 2 using the classification (see 4.2). the ratchet wheel under gravity, should its operathfg mechanism fail. Table 2 Safe Working Load of Chain Blocks 5.4.6 Adequate arrangements shallbemade to ensure (Clause 4.3) the pawl does not seize on the pawl pin. S1No. Classification SafeWorking Load 5.5 Bearings 0/0ofWorkhg LoadLimit Bearings used shall be of plain or rolling type. (1) (2) (3) 5.5.1 Roller bearings shall conform to IS 4215 or O Ml 100 IS 5669 or IS 7460 or IS 7461 (Part 1) or IS 7461 ii) M2 80 (Part 2) orIS 7461 (Part 3). iii) M3 63 5.5.2 Bronze or Cast Iron Plain Bearings iv) M4 50 Whenplainbearings areused,their maximum bearing 5 CONSTRUCTION pressure shall not exceed the following values unless “ manufacturer can produce evidence satisfactory to 5.1 Frame thoseconcerned that ahigher pressure ispermissible: The frame of the block shall be designed for proper In Bronze In Cast Iron strength and it shall maintain alignment under all Bearings Bearings expected conditions of service. MN/mz MN/mz 5.2 Gears Steel shaft – ground 17 14 The gears shall be designed for proper strength and Steel shaft– not ground 14 10 for surface durability such as to afford efficient operation throughout the period guaranteed by the NOTE — 10MN/mz= 1kgflmmz. manufacturers. Incaseofenclosedgearing,meansshall 5.5.3 Plain Bearings in Materials Other than Cast be provided for ample lubrication. Iron or Bronze 5.3 Load Brakes Higher bearing pressures than those specified in5.5.2 may be used by the manufacturer, if evidence is All pulley blocks which are not inherently self- produced that higher pressure may be used. sustaining when thepull ofthehand chainisremoved, shall be provided with an automatic mechanical load 5.6 Lubrication brake which willprevent self-lowering oftheloadand arrest and sustain load in all working positions. The The block shall be provided with adequate facilities load brake shall also allow smo oth lowering of the for lubrication unless materials with inherent load without serious overheating w hich may impair lubricating properties are used. efficient working of the block. 5.7 Suspension Fittings 5.4 Pawls 5.7.1 Hook 5.4.1 Pawls shall beof sufficient strength to arrestthe Point hooks with shank up to 160t shall conform to full load from lowering due to gravity. IS 15560. It shall be forged from steel and the shank 5.4.2 Therelative width andpositioning oftheratchet shall be either: wheel and the pawl shall be such as shall ensure full a) provided with nut or screwed collar of out side engagement irrespective of wear of the friction faces. diameter of atleast 1.5 times the diameter of the shank engaged by the nut or screwed collar 5.4.3 The pawl andthe ratchet shallbemade ofsteel, on the load side shall be equal to atleast 0.66 hardened and tempered or given an equivalent times the diameter of the shank before being treatment to provide satisfactory degree of wear interrupted bydrilling forpins orother fixings, resistance together with toughness. The hardness of or the pawl tip shall not be lessthan 40 HRC andthat of ratchet not lessthan 30 HRC. b) so shaped tlom the solid asto afford the same security as though a nut were fitted as in 5.4.4 The pawl shall engage with the ratchet wheel 5.7.1 (a). either bymeans ofaspring other than atension spring or by some other equally effective means. The hooks shallbe sodesigned that itshall be free to swivel in the loaded conditions without twisting the 5.4.5 The pawl shall be sopositioned that itengages load chain. Swivel hooks shall be capable of being 4 IS 3832:2005 lubricated both initially on installation and during 5.8.5 Guide servicing. Where the means of attachment of a shank Means shall be provided to ensure ~ffeetive guidance hook is dependent on a split collar mating with an of the load chain into chain wheel ~ockets. enlarged head on the shank, the means of retention shall be secure. However, it is in agreement between 5.8.6 Stripper the manufacturer and purchaser. There shall not be any welding inthe hooks. A stripper shall be provided to ensure effective disengagement of the load chain wheel. NOTE — Safetylatchesarerecommendedbutattentionis drawntothestatutoryregulationscoveringIitlkg operations. 5.8.7 Idler Wheel In somecasesthoserequirementsaffecthooks,demanding safetycatches,mousingoruseof‘C’ hooks. The chain pulley blocks shall be provided with idler 5.7.1.1 Top hooks wheels soshaped asto avoid the twisting ofthe chain when passing around. Where provision ismade forthetophook toswivel, it shall remain positionally stable under load. 5.8.7.1 The pitch diameter ofthe idler wheels shall be such that the bending action of the link is avoided. 5.7.1.2 Bottom hooks 5.9 Anchorages Bottom hooks shall be free to rotate under load so as to prevent twisting of the load chain. If threaded The load chain anchorages, associated fittings and the components are used, they shall be sealed against frame work at the slack end shall be at least equal in ingress of moisture. Welding shall not be used as a strength to 2.5times themaximum tension inthe load method of retention or sealing. chain when the working load limit isbeing lifted. 5.7.2 Other Fittings 5.10 Hand Chain Suspension fittings other than hooks shall be of 5.10.1 Grade sufficient strength to affect a static factor of safetyof Thematerial, welding andfinish shallbeat leastequal not less than four unless otherwise required by the to that of grade 30 chain as per IS 2429. Hand chain relevant Indian Standards. shall be untested, pitched and polished condition. It 5.7.3 All suspension fittings shall be readily should have proper seating in hand chain wheel and detachable for inspection of stressed parts, such as should not over ride. shanks. 5.10.2 Link Dimensions 5.8 Load Chain The following dimensions are recommended: 5.8.1 Grade Nominal Size Pitch Outside Width The minimum requirements of a l oad chain pulley mm mm mm block shall not be less than that of Grade T (8) chain 5 22.5 * 0.5 17 +0.5 conforming to IS 3109 (Part 2). 6 22.5 * 0.5 20 * 0.5 NOTE — If chain of grade 100 is used,the percentage elongationshallnotbelessthan10. 5.10.3 Length of Chain 5.8.2 Chain Engagement The length of the hand chain shall be such that the Means shall be provided to guide the load onto the lowestpoint ofthe suspended loop shall hang at least load chain wheel. 400 mm above the operating level. 5.8.3 Length of Chain 5.10.4 The hand chain shall bejoined without twist. The method ofjoining shall ensure that there are no Total length of the load chain shall exceed the sharporprojecting edges, causing anyharm during its minimum length required togivetheprescribed range used. of Iitl by not less than three links per fall to ensure that the slack and ancncourage isnot loaded. 5.10.5 Hand Chain Wheel 5.8.4 Load Chain Wheel Handchain wheels shallbeprovided with flanges and designed to ensure effective operation with the hand Theloadchainwheelshallbemadeofsuitablematerial chain. for use with load chain employed and be of adequate strength and shall be suitable designed to ensure 5.10.6 Hand Chain Guide effective operation ofthechainandshouldbeproperly secured with shaft, preferably with splines. The hand chain guide shall be so designed that the 5 ..