IMPROVEDSEJ(LAYING, MAINTENANCE & INSPECTION.) BY:- Harpal Singh (SSE/PWAY/RPJ) INTRODUCTION On Indian Railways IRS design switch expansion joints were laid on both ends of LWR in lieu of Buffer rails. These SEJs are failing frequently as there were many cases of fracture of Stock rail/Tongue rail which is affecting Safety of running trains . DRAW BACK OF CONVENTIONAL SEJ Stock rail fracture takes place at its reduction of section and due to involvement of bend. In case of fracture it is very difficult to carry out emergency repair. . Stock rail give up at about 20 – 40 mm away from the point of section reduction (throat) and 700 mm from its tail end which is left unsecured against longitudinal movement. Chipping on throat of Stock rail & Tongue rail. Not suitable to for laying on curves sharper than 0.5 deg. Level difference at throat of Tongue rail & Stock rail. Hammering and breakage of bearing plates. Rivets of MS flat which was provided to Stock rail are loosened and unusual sound heard while running of trains. The broken piece keeps moving away by hammering of playing wheels and discontinuity with wider gap in track especially in winter. Spacing of sleepers at mid of SEJ 700 mm. CONVENTIONAL SEJ . 0 deg. To avoid any fractures in the bent portion of Stock rail & Tongue rail. Suitable to lay on curves sharper than 0.5 deg. .REQUIREMENTS OF IDEAL SEJ To avoid bends in design of the Stock rail and Tongue rail. and up to 4. In case of fracture part of Stock rail piece shall not move from its original position due to longitudinal forces. Suitability for higher speeds. Suitability to higher axle loads. TYPES OF IMPROVED SEJ SEJ with one gap Developed by M/s Rahee Industries Ltd. Works. & M/s Chintuparni Engg. SEJ with two gaps Developed by M/s Bina Metalway. Barabanki. . Jamshedpur. Calcutta. 3. Design suitable up to 200mm max. gap at the time of installation/ replacement of SEJ.2º.1.ADVANTAGES OF IMPROVED SEJ Advantages of SEJ with one Advantages of Two gap SEJ gap : The maximum gap is 57 mm which lead to lesser impact under No bends in tongue and stock It gives the field staff better control in providing correct nominal rail. Status of stock rail is static as compared to moving type in IRS type of SEJ.2. It is suitable to be laid in curves in steps of 1º. . Check rails guard against excessive play of worn out wheels. gap.3º.5mm) in conventional type.4º by supplying pre curved stock rails. The minimum head width of tongue rail is more than 61% of full rail head width (44.5º. The wear prone areas of heads of stock and tongue rails are pearlitised through a special process to achieve a hardness of 320 BHN Maximum head thickness of stock rail is 89. passing wheels as compared to gap of 74 mm in IRS type. Only 5 sleepers of standard SEJ on PSC assembly are used.75mm) as against 35% of head width (25.5º. The tongue rail being slender can be curved at site by the field staff.5 mm as compared to 72 mm in IRS type of SEJ which in turn increases wheel support.5º. 5 mm 42 mm Increase life 5 Head thickness of Stock rail 72 mm 86 mm More wheel support 6 Status of Stock rail Unsecured Secured Safety ensured 7 Suitability to lay on curves Limited up to 0.0 deg.COMPARISON BEETWEEN NORMAL SEJ AND MODIFIED SEJ S. Scope for use 8 Provision of 1 in 20 can`t in SEJ sleeper Not provided Provided Built up twist avoided 9 Failure rate Very high For last five years no failure is reported Decreases maintenance cost .No Features Normal SEJ Modified SEJ Merits 1 Bend in rails 1 in 8 No bend No breakage 2 Sleeper spacing at increases stability Mid of SEJ 700 mm 600 mm 3 Designed for 80 mm/120 mm 180 mm Less wheel Impact in large gap 4 Head thickness of Tongue rail 25.5 deg. Can be laid up to 4. Inspection and records. Special maintenance. Installation works.INSTALLATION OF MODIFIED SEJ Preparatory works. Routine maintenance of Modified SEJ. Reference marks and gap measurements. Unusual occurrences. . . Equipment for protection work.PREPARATORY WORKS Details plan of LWR track showing exact location of SEJ to be decided. Material required as follows : Material required for one set of Modified SEJ as per drawing. Sufficient manpower with tools. Rail cutting equipment. Sufficient number of 6. Distance between the ends of adjoining LWR between in which Modified SEJ to be laid shall be equal to length of Modified SEJ-2x13 m. Sufficient number of 1 m fishplates with suitable clamps.5 m long ultrasonically tested closure rails of same section. block to be obtained and both ends of rail shall be cut as per marking. . SEJ shall be pre-assembled as per drawing on PSC sleepers and kept ready beside of proposed location with suitable arrangement to shift on to track. SEJ gap to be adjusted as per LWR manual during distressing temperature. Welding of both ends to be done as per availability of block. The existing PSC sleepers and rails to be removed.INSTALLATION WORKS Impose SR of 30 KMPH on the particular KM where SEJ to be inserted. Minimum 1 hr. Pre-assembled SEJ to be inserted in track & joined with suitable fish plate & clamps. Ballast shall be recouped and track shall be attended to correct line and level. Ballast shall be leveled. A string shall be stretched across track over the saw marks of reference for measuring SEJ gap with respect to tip of Tongue rail/Edge of Stock rail. Marking on pillars be shall be in form of saw marks.REFERENCE MARK AND MEASUREMENT Pillars shall be erected at Centre of SEJ and reference marks shall be marked on these pillars on either side of track during distressing. . SEJ gap to be provided 40 mm. packed and aligned if necessary. the Key man shall keep special watch on the SEJ. Fastening shall be renewed on not more than one rail seal at a time. During daily patrolling. Oiling and Greasing of Tongue rail & Stock rail shall be carried out once in fortnight. . Once in fortnight the SEJ shall be checked.ROUTINE MAINTENANCE & SPECIAL MAINTENANCE All fastening shall be complete and well secured. SEJ gap to be adjusted during distressing which shall be carried out as per provisions laid in LWR manual. . both damaged SEJ rail and undamaged SEJ rail on opposite side shall be replaced by closure rail and connected to LWR/SWR with suitable clamps and fishplates. New SEJ to be installed.UNUSUAL OCCURRENCES If another SEJ is not available for replacement. INSPECTION & RECORDS Inspection shall be carried out on every fortnight during the two coldest and hottest months of the year during minimum and maximum temperatures at supervisory level and senior level. . Recording of inspection notes as per preformat given in LWR manual. Alternatively once in two months during other months at supervisory level. Compliance of observations of deficiencies is also entered in the inspection register. THANK YOU .