CENTRAL MARKS DEPARTMENT II (Legal) Our Ref: CMD-II(L)/16:

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1 CENTRAL MARKS DEPARTMENT II (Legal) Our Ref: CMD-II(L)/16: Subject: Revision of existing STI DOC:STI/8737/5 July 1999 for Valve fittings for use with LPG Cylinder of more than 5 litre water capacity as per IS 8737:1995 Lot Inspection Sampling Modification. This is with reference to the proposal for modification of sample size of finished lots of valve fittings for use with LPG Cylinders as per IS 8737:1995 and the definition of control unit in the STI for IS 8737:1995 sent by HRBO, (NRO) vide their note No. HRBO/G-5 dated HRBO s above proposal was circulated to all RO/BOs vide CMD s note dated (hosted on Intranet on ). Vide this note, PRBO was requested to modify the above proposal of HRBO based on the comments if received from any RO/BO/SBOs and forward a copy of the finalized proposal through DDGN, NRO. Thereafter, a reminder was sent to all RO/BOs vide note dated circulated through mail on with a request to examine the said proposal and send the comments, if any, directly to PRBO by so that further action can be taken in this regard by PRBO. We are now in receipt of note no. PRBO/IS 8737 dated along with draft STI DOC: STI/8737/6 for LPG valves as per IS 8737:1995. In their note, PRBO has informed that they have not received any comments from RO/BOs, however they have drafted the revised STI as STI DOC: STI/8737/6 with modification in sampling plan at their end (the sampling plan has been reported made similar to the latest STI as per IS 9798:2013 by PRBO) and also modified the definition of control unit. The above proposed draft STI has been approved by DDGN on On perusal, it is observed that PRBO has prepared a compressed STI by excluding formats for maintaining the testing records of dimensions of components by the licensees and has also removed the drawings of different components of LPG valves from the existing STI/8737/5 July 1999.The comparative details of sampling of valves in the existing STI, HRBO s proposal dated and as proposed by PRBO are given below: Existing STI HRBO s Proposal PRBO s Proposal Lot Size No. of Lot Size No. of Lot Size No. of valves valves to valves to to be tested be tested be tested Upto 500 Valves 20 Upto Upto valves and above and above and (2 nos, above per each additional thousand or part there off)

2 The definition of control unit given in the existing STI, proposed by HRBO initially and as finalized by PRBO is also reproduced below: i) Existing STI For the purpose of this scheme, the control unit shall consist of a lot of forged valve bodies of the same type & size forged in a day from the material of the same supplier under similar process of production. ii) HRBO s Proposal A Control Unit consist of a batch of forged bodies of the same type and size forged in a day from the material of the same supplier under similar process of production. iii) PRBO s Proposal A Control Unit shall consist of lot of forged valve bodies of the same type and size forged in a day/different days from the material of the same consignment/supplier under similar process of production. A copy of above revised STI DOC: STI/8737/6 is enclosed. All RO/BOs are requested to examine the STI and send their comments, if any, within 30 days directly to PRBO. It is also requested to examine the need for retaining the formats and the drawings as part of the STI that whether these should be a part of STI as in the case of STI no.5 (for guidance) and send their views to PRBO for taking action on the same by them. Based on the feedback/comments received, PRBO shall make a recommendation to CMD-II (L) for adoption of the final STI. This is issued with the approval of the Competent Authority. Head, CMD-II (Legal) (Sunil Kumar) Sc. F Circulated to : All BOs/ROs/SBOs/BIS Labs. Copy to: i) Head (ITSD)- With a request to host this circular with STI on Intranet & website. ii) Head (MED) iii) Head (PRBO) iv) Head (MSD)

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4 DRAFT SCHEME OF TESTING AND INSPECTION FOR CERTIFICATION OF VALVE FITTINGS FOR USE WITH LIQUEFIED PETROLEUM GAS (LPG) CYLINDERS OF MORE THAN 5 LITRE WATER CAPACITY ACCORDING TO IS 8737: LABORATORY - A laboratory shall be maintained which shall be suitably equipped and staffed, where different tests given in the specification shall be carried out in accordance with the methods given in the specification. 1.1 All testing apparatus shall be periodically checked and calibrated and records of such checks/calibration shall be maintained Tensile testing machine shall be calibrated at least once in a year. Izod impact testing machine shall be calibrated at least once in three years Various pressure gauges used shall be calibrated once in a month The firm shall procure a set of certified gauges for inspection of different components. A typical set of these gauges is given in Annex - I for guidance only Master gauges against which inspection gauges are checked periodically shall be sent for rechecking in an independent laboratory once in three years The pyrometer used for heating furnace shall be calibrated once in every six months. 2.0 TEST RECORDS All records of tests and inspection shall be kept in suitable forms approved by the Bureau. 2.1 Copies of any records and other connected papers that may be required by the Bureau shall be made available at any time on request. 3.0 QUALITY CONTROL - It is recommended that, as far as possible, Statistical Quality Control (SQC) methods may be used for controlling the quality during production as envisaged in the scheme [See IS:397 (Part I) to IS:397 (Part IV)]. 3.1 In addition the provision of quality system specified in IS/ISO: 9001 may be complied as far as possible as appropriate to the activities of the organization. 4.0 STANDARD MARK - The Standard Mark, as given in Column (1) of the First Schedule of the licence, shall be stamped on the hexagonal flat of valve body, provided always that each valve, so marked, conforms to every requirement of the Specification. 5.0 OTHER MARKINGS - In addition, each valve shall be stamped with the following on the hexagonal flats of the valve body: (a) Ma ufa turer s ide tifi atio ark; (b) Quarter and year of manufacture;

5 (c) Maximum working pressure in MPa; (d) Control unit number; and (e) Licence No. (CM/L - xxxxxxxxxx) DRAFT 6.0 CONTROL UNIT A CU shall consist of lot of forged valve bodies of the same type and size forged in a day/different days from the material of the same consignment/supplier under similar process of production. 7.0 LEVELS OF CONTROL - The tests and inspection indicated in Table 1 attached and at the levels of control specified there in, shall be carried out on the whole production which is covered by this scheme and appropriate records and charts maintained in accordance with Paragraph 2 above. All the production which conforms to the Indian Standard and covered by the licence shall be marked with the Certification Mark of the Bureau. 7.1 Each control unit of finished valves shall be offered for inspection to BIS before dispatch (See Table 3). Valves failing to meet the requirements of the specification shall not be marked with the BIS Standard Mark A certificate as per Annex-VI shall be issued by BIS in respect of valves approved for marking with BIS Standard. 7.2 Valve without thread outlet shall be fitted with a protection cap and inlet shall be fitted with a thread cap before dispatch. 7.3 The manufacturer shall maintain a system of works inspection at all stages of manufacture to ensure that the individual valve fittings are free from all manufacturing defects and comply in all respects with the requirements of the Indian Standard Specification 7.4 LOW TEMPERTURE & HIGH TEMP TEST: Low temperature, test and high temperature test shall be done on assembled valves as per Annex H of IS 9798 and then tested for the performance in open and closed position (Temperature Range - 20 C to 65 C). 7.5 FORGING & MACHINING: The licensee will possess all the requisite infrastructure for the forging and machining of the valve housing in their own premises. Under no circumstances, the forgings of valve housing (body) or machining there of shall be permitted to be sub-contracted or bought from outside. 7.6 BOUGHT OUT COMPONENTS - All the components manufactured/bought from outside shall be inspected by the licensee as per details given in Table 2 and records maintained. 7.7 Guidelines indicated in Annex-V shall be followed during component/assembled valve inspection. 7.8 Design, Fabrication The valve shall conform to all the requirements given in clauses 4, 5, 6 & 7 of IS 8737 : At the time of design approval the valve shall be checked for conformity to all the requirements of the specification and those given in the approved drawing including the cycle test. Whenever there is a change in material or design of the valve, it shall be retested for conformity to all the requirements of the specification.

6 DRAFT Cycle Test The valve shall perform satisfactorily at not less than 5000 cycles of opening and closing operations in accordance with requirement of Clause 9.2 of IS 8737:1995. After the cycle test the valve shall be subjected to the pneumatic test as per details given in Table 1 and shall perform satisfactorily. 8.0 MATERIAL: The manufacturer shall declare in their scheme of manufacture/drawing the relevant specification/chemical composition of the raw material (Brass) used for valve body, which meets the requirement of forgings as given in IS 8737: One sample from each consignment of raw material received in the factory shall be analyzed for chemical composition. The composition shall be such that the material shall be compatible under the conditions of service with LPG. If the material is accompanied by a test certificate, further testing is not required. The manufacturer of the valve should establish means to identify the valve with the certificate. Material with seams, cracks, lamination or other injurious defects shall not used. 8.2 Each consignment of rubber components received shall be subjected to the following tests at the frequency given in Table 2: i) Shore hardness (as given in approved drawing) ii) Immersion test as per. for al e seat a d. for O seal of I 8.3 The relevant specification for the raw material for other components shall also be declared by the manufacturer and clearly indicated in their drawings and scheme of manufacture. 9.0 In respect of all other clauses of the specification and at all stages of manufacture, the factory shall maintain appropriate control and checks to ensure that their products conform to various requirements of the specification REJECTIONS - A separate record shall be maintained giving information relating to the rejection of the production not conforming to the requirements of the specification and the method of its disposal. Such material shall in no circumstances be stored together with that conforming to the specification SAMPLES - The licensee shall supply, free of charge, the samples required in accordance with the Bureau of Indian Standards (Certification) Regulations, 1988, as subsequently amended, from the factory or godowns. The Bureau shall pay for the samples taken by it from the open market REPLACEMENT/REPAIR - Whenever a complaint is received soon after the goods with standard mark have been purchased and used, and if there is adequate evidence that goods have not been misused, defective goods or their components are replaced or repaired free of cost by the licensee in case the compliant is proved to be genuine and the warranty period (where applicable) has not expired. The final authority to judge the conformity of the product to the Indian Standard shall be with the Bureau. The firm shall have its own complaint investigation system as per IS/ISO In the event of any damages caused by the goods bearing the Standard Mark, or claim being filed the o su ers agai st BI ta dard Mark a d ot o for i g to the rele a t I dia Standard, entire liability arising out of such non conforming product shall be with licensee and BIS shall not in any way be responsible in such cases.

7 DRAFT 13.0 STOP MARKING - The marking of the product shall be stopped under intimation to the Bureau if, at any time, there is some difficulty in maintaining the conformity of their product to the specification, or the testing equipment goes out of order. The marking may be resumed as soon as the defects are removed under intimation to Bureau The marking of the product shall be stopped immediately if directed to do so by Bureau for any reason. The marking may then be resumed only after permission by the Bureau. The information regarding resumption of markings shall also be sent to the Bureau PRODUCTION DATA - The licensee shall send to BIS production data duly authenticated by a Chartered Accountant at the end of every operative period as per item (b) of column 4 of the second schedule of the licence, in the form CM/PF/604. TABLE

8 IS 8737 :1995 VALVE FITTINGS FOR USE WITH LPG CYLINDERS TABLE 1 LEVELS OF CONTROL (Para 7 & 8 of the Scheme of Testing and Inspection) DRAFT TEST DETAILS LEVELS OF CONTROL Cl. Requirements Test Method No. of Lot Size Samples 3.1 Material (Composition) Clause Reference i)valve Body As declared One Each consignment -- ii)other Components As declared One Each consignment Forging Tensile strength and Elongation. Impact strength 4 i) External Threads on Valve Inlet 3.3 & 3.4 IS 8737 According to sample plan given in Annex A of IS 8737 Each consignment -- 4 IS 8737 One Valve Every 15 Minutes from each machine -- Freque ncy Remarks This test will not necessary if the consignment is accompanied by a certificate from the producer (Refer Cl. 8.1 of STI If any of the sample fails, twice the number of samples of the original sample size shall be tested from the same control unit. If any of the sample fails to meet the requirement, the entire control unit shall be rejected and scrapped. i) The threads shall be checked with the help of certified gauges (L1 & L8) and truncation gauges. Valve threads having burrs shall be cleaned for burrs and then checked. ii) In case of failure all the valves produced in preceding 15 minute shall be checked. 4 ii) Valve in-let connections All dimensi ons IS 8737 Each Valve Valve Outlet 5 IS 8737 Each Valve Valves failing is any of the critical dimensions shall be rejected. 6 Constructional Requirements: Dimensional Check Minimum Thickness of Valve body 6.1 to 6.7, 6.9 IS 8737 Each Valve IS 8737 One piece Each Control Unit -- In case of failure two samples shall be tested. Repeat failure shall result in rejection of the lot.

9 IS 8737 :1995 VALVE FITTINGS FOR USE WITH LPG CYLINDERS TABLE 1 LEVELS OF CONTROL (Para 7 & 8 of the Scheme of Testing and Inspection) TEST DETAILS LEVELS OF CONTROL Cl. Requirements Test Method No. of Lot Size Frequency Samples Valve body seat profile Dimensions and profile Visual Smoothness free from cuts and burrs 8.1 Hydrostatic Test 25.5kgf/cm 2 (Valve housing) Clause Reference As declared/given in the drawing Longitudinal section will be cut and seat profile checked with the help of shadowgraph or templates -- With the help of magnifyi ng glass One Valve 8.1 IS 8737 According to sample plan given in Annex A of IS 8737 for tensile strength test. Each Shift DRAFT Remarks -- In case the profile is not as per drawing double the number of sample shall be tested. Repeat failure shall result in rejection of the lot. Each Valve Valve housing having cuts, burrs or other defects on the seat shall be rejected. 8.2 Pneumatic Test 8.2 IS 8737 Each Valve In case of any failure, all the remaining valve housings shall be subjected to this test Tightness of Joint IS 8737 Each Valve Packing (in valve outlet) and valve spindle (Pressure of 1000 mm water column from outlet) Tightness of valve IS 8737 Each Valve spindle and valve housing (Pressure of 17 kgf/cm 2 with valve spindle in closed position) Tightness of joint packing and housing (Pressure of 17 kgf/cm 2 with valve spindle in open position from inlet) IS 8737 Each Valve Cycle Test 9.2 IS 8737 One Valve -- After 20,000 Valves of same type or atleast once in a month This test shall be carried out in presence of BIS Officer. 6.6 Security (Protection) Cap/ Metallic Security Nut Sealing test at 17 Kg/cm 2 by fitting to the Valve in open position Five Caps/ Nuts Each lot -- As per the approved drawing as applicable

10 IS 8737 :1995 VALVE FITTINGS FOR USE WITH LPG CYLINDERS TABLE 2 LEVELS OF CONTROL (Para 7 & 8 of the Scheme of Testing and Inspection) TEST DETAILS LEVELS OF CONTROL Cl. Requirements Test Method No. of Samples Lot Size Frequenc y Clause Reference A Internal Components DRAFT Remarks i) Rubber & other moulded Components a) Immersion tests for compatibility Annex D IS 9798 one Lot of 1000 pcs. or less b) Shore Hardness test As per approved 1% with a Each drawing minimum of 10 Consignme pcs. or on test nt slab c) High temperature test C Annex H IS finished valves One control unit Once in a week -- d) Low temperature test (- C -do- -do- -do- -do- -do- -- ii) Spring a) Load test As per approved drawing 1% with a min of 5pcs. & max of 20pcs. Each Consignme nt -- Counter check at assembly stage b) Permanent set test Annex II 5 pcs. -do- -- -do- c) Nitric Acid Immersion test Annex III 5 pcs. -do- -- -do- d) Dimensional check As per approved drawing iii) Security (protection) cap spring 1% with a min of 5pcs. & max of 20pcs. -do- -- -do- a) Nitric Acid Immersion test Annex III b) Dimensions As per approved drawing 1% with a min of 5pcs. & max of 20pcs. -do- -- -do- -do- -do- -- -do- A iv) Brass Components a) Upper Spindle (Dimensions) b) Lower Spindle (Dimensions) As per approved 1% with a min Each drawing using of 5pcs. & max Consignme Certified gauges of 20pcs. nt -do- -do- -do c) Adjusting Screw -do- -do- -do d) Seat & Spindle Assembly (Dimensions & Visual) As per approved drawing. Height with dial indicator Each Piece

11 IS 8737 :1995 VALVE FITTINGS FOR USE WITH LPG CYLINDERS TABLE 2 LEVELS OF CONTROL (Para 7 & 8 of the Scheme of Testing and Inspection) TEST DETAILS Cl. Requirements Test Method No. of Samples Clause Reference B Process Checks LEVELS OF CONTROL Lot Size Frequency DRAFT a) Spindle Height As per Annex IV Each Piece b) Spindle Travel -do- -do Remarks c) Position of Joint Packing w.r.t. Lower edge d) Riveting Depth of Lock Screw e) Descrewing Torque for the adjusting screw -do- -do See also Annex VII -do- -do kg-cm 1%

12 Table 3 DRAFT (Para 7.1 of the STI) Inspection of finished lot: After testing and inspection by the firm, each lot shall be offered to BIS for release. Numbers of valves shall be selected by BIS officer as per sampling plan given below. The selected valves shall be tested for outside threads on valves inlet, Pneumatic Test specified in cl. 8.2 of IS 8737: 1995 and all other dimensions shall be checked as per approved drawings for particular collar diameter valve. The valves shall also be tested for control dimensions (See Annex-IV). The sampling plan will be as under: Lot Size No. of valves to be tested Remarks Upto 500 valves 20 In case of any failure observed the lot shall be reoffered by the manufacturer after complete recheck. Any repeat failure shall result in the rejection of and above (2nos. per each the whole lot. Lot can be additional thousand or part reoffered only once. All there off) rejected valves shall be scrapped. Note: In case during inspection by BIS officer valves are found with defects like burrs on valves inlet/outlet connection etc. which may likely to affect the result of inspection, the firm may be advised to segregate/rectify such valves and reoffer for inspection. A e I.

13 ANNEX - I (Para of the Scheme of Testing and Inspection) DRAFT LIST OF GAUGES FOR VALVE HOUSING : S.No. Gauges Type of Limits Remarks 1. 8 ± 0.5 Depth Gauge H-8.5 L ± 0.1 Dial set up Go-4.6 No Go Ø 0.0 Plug Go-13.2Ø No Go Ø Plug Go-11Ø No Go ± 0.1 -Ø 0.02 Plug Go Ø No Go ± 0.1 Depth Gauge H- 1.1 L ± 0.1 Dial Set up H-32.6 L Ø ± 0.15 Plug Go- 17 Ø No Go ¾ NGT Standard Thread Ring Gauge Standard Transaction Gauge 10. / Ø TPT WHIT Thread Plug Ø ± Plug Go Ø No Go Ø ± Snap Go Ø No Go ± Dial Set up H-15.5 L Ø ± 0.1 Plug Go- 12 Ø Ø ± ± Ø ± Vernier or Profile Projection No Go Go Ø No Go Template Go- 6.8 No Go- 7 Snap Go Ø No Go Indirect Gauging

14 ANNEX II DRAFT Test Method for Permanent Set Test (Table 2 of Scheme of Testing and Inspection) The purpose of set test is to ascertain the loss in compression load after being compressed for 24 hours and maintaining a gap of 0.1 to 0.3mm in between the coils. Test Method: 1. Test the spring for the compression load on a spring tester as per requirements given on the drawing and record the load observed. 2. The spring shall kept between two parallel plates and then compressed in such a way that there is a gap of 0.1 and 0.3 mm between the coils. The gap may be checked with the help of a feeler gauge (Strips of wax paper of known thickness may be inserted in-between the coils for uniformity). 3. The spring shall be kept in the compressed condition for 24 hours after which the load shall be released. It shall then be kept for 5 hours in free state. 4. The spring shall be checked again for load test as in (1) above. 5. The difference in the two values of the load applied in (1) and (4) above shall not be more than 100 grams. NOTE: The spring under test should never be compressed to its solid length since it ay spoil the spring and affect the results. Springs compressed to solid length shall be rejected.

15 DRAFT ANNEX III (Table 2 of Scheme of Testing and Inspection) Test for Rust-Proofness of springs (Stainless Steel) (Nitric Acid Immersion Test) Each lot of springs shall be subjected to rust proof test as per details given below: 1. The spring shall be degreased and buffed with a fine abrasive paper. 2. These shall then be kept immersed in a 2% Nitric Acid solution for one minute. 3. The result can be observed immediately when the material has been taken out of the Nitric Acid solution. If the material is still bright it is rust-proof; if it is black, the material is not rust-proof.

16 DRAFT ANNEX IV (Table 2 of Scheme of Testing and Inspection) CONTROL DIMENSIONS TO BE INSPECTED ON ASSEMBLED VALVES: 1. Spindle height 8.5 ± 0.3mm to be measured with dial indicator C 2. Spindle travel mm/ - 0mm to be measured with dial indicator C 3. The position of joint packing viewed from the lower edge of the collar must be mm/ - 0.2mm measured with dial indicator. On account of the measuring pressure of dial indicator, this dimension is permitted to exceed the tolerance by 0.05mm on the negative side. C 4. In consideration of riveting and the spindle travel the adjusting screw shall not project beyond the surface where the threads start in the valve housing. It shall be flush with this surface within 0.2 ± 0.2mm C STRENGTH SPECIFICATION: 5. The riveting of the adjusting screw at the inlet of the valve should be checked for unscrewing torque which should be 5 kg-cm minimum. NOTE: C Critical Dimension

17 DRAFT ANNEX V (Para 7.7 of Scheme of Testing and Inspection) 1. Before inspection all rubber components shall be cleaned of all the moulding wax by ashi g the i hot ater at a out C. 1.1 After washing, the rubber components should be completely air-dried. 2. Rubber components with fins, burns, moulding defects, loose particles, cavities or having rough surface shall be rejected. 3. Stampings of markings on the hexagonal flats shall be effected in such a way that the internal bores of the valve housings do not deformed. This will be ensured with the help of certified gauges. 4. An approved drawing of all the components shall be made available to the BIS Inspecting Officer for reference. 5. Hydrostatic test shall be carried out on samples of valve housing before assembly and these may be counter checked by BIS. 6. Valve housing with pits, burrs, black spots, cracks, cavities and other defects shall be rejected.

18 ANNEX VI (Para of the Scheme of Testing and Inspection) Test Certificate for Valve Fittings for use with LPG Cylinders DRAFT IS 8737 Name of the Manufacturer Certificate No: Purchaser: Order No. Control Unit No: Quantity offered for inspection: Valve fittings description: date: Batch No: CM/L-xxxxxxxxxx This is to certify that the valve fittings as mentioned below were inspected at M/s. and these meet the requirements of IS 8737: 1995 and Drg. No: Results of Inspection: 1) Visual inspection 2) External threads on Valve inlet 3) Valve out-let connection 4) Pneumatic Test a) Tightness of joint packing(in valve outlet) & Valve spindle (Cl of IS 8737: 1995) b) Tightness of valve spindle and valve Housing (Cl of IS 8737: 1995) c) Tightness of joint packing and housing (Cl: of IS 8737: 1995) 5) Cycle Test of batch number No.of Valves Inspected Passed Rejected Fro a ufa turers test re ord a) Tensile strength and % elongation b) Impact strength Quantity Passed: Rejected valve fittings and the method of their disposal: (Signature) Name & Designation of the Officer representing the Licensee (Signature) Inspecting Officer Bureau of Indian Standards NOTE: A copy of the certificate may be sent to PESO, Nagpur

19 DRAFT ANNEX VII Following method shall be adopted for inspection of I.D. of Joint Packing. a) ID & OD of the sealing washer shall be checked with the help of approved plug gauge and ring gauge and in the manner specified on the drawing No inspection of I.D. will be required after the fitment of joint packing in the valve housing b) Any cross check if so desired by the inspection authority should be done on pieces which are not removed from assembled/sub-assembled valves, but from stocks, inspected and kept ready for assemblies. c) To obviate the effect of reduced areas of contact, fitting pressure, compressibility and resilience of rubber, the plug used for checking GO size should measure Ø 9.15mm (i.e., mm) should drop freely and should weigh approx 20 grams. d) The NO GO plug should measure Ø 9.4mm (i.e., mm) should weigh 20 grams approx and should not pass through by its own weight. e) The same type of extra allowance of 0.05mm could be applied for measurement/gauging of all diameters and heights.