No. of Single leaf Sector Gates 2 Clear span of opening 7.0m Cylinder rebate size. Sill level inner gate Gate crest level - inner.

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1 YARINGA MARINA SINGLE LEAF SECTOR GATES 1.1 Leading Particulars No. of Single leaf Sector Gates 2 Clear span of opening 7.0m Cylinder rebate size To suit Sector gate depth above sill - 6.5m outer Sill level outer gate -2.00m Gate crest level - outer +4.5m Sector gate depth above sill - 4.5m inner Sill level inner gate -0.50m Gate crest level - inner +4.00m Pier top level +4.0m Normal basin level +2.00m to +4.00m Max. downstream tide level +4.00m Min. downstream tide level -0.50m Type of actuators Hydraulic cylinders and power unit Hydraulic system max working 220 bar pressure Gate operating time approx 1 minute (opening or closing) 1.2 Sector Gate Specification Single leaf Sector gates will be provided at each end of the lock. Sector gates are selected to allow lock filling at all normal unbalanced head differentials by using side sluicing into the gate recess i.e. cracking at the recess side of the gate, prior to opening at the far side. This minimises disturbance in the lock at low water levels. The gates will be designed structurally taking into account the permissible stresses and the likely deflections of the structure to ensure the performance of the sealing system is not impaired. The gates will be designed to move from fully open to fully closed (or vice versa) within a period of approx 1minute. NB: this does not 1

2 include time taken for the water equalisation process and vessel transit. The Sector gates will be designed as rigid structures to allow hydraulic cylinder operation, taking into account the hydrostatic conditions stated below: Outer Gate Inner Gate a) Normal Static load Condition on-seating - The Sector Gate will be designed to withstand the design flood water level at +4.5m with the lock dewatered. b) Normal Static load Condition off-seating - The Sector Gate will be designed to withstand the max lock water level at +4.00m and tide at -0.50m. c) Normal Operating Condition - The Sector Gate will be designed to operate for side sluicing at lock level at minimum -0.50m and tide level at +4.00m. After which, the gate will fully open in near balanced conditions. d) Normal Static load Condition on-seating - The Sector Gate will be designed to withstand the design basin water level at +4.0m with the lock dewatered. e) Normal Static load Condition off-seating - The Sector Gate will be designed to withstand the max lock water level at +4.00m and basin at +2.00m. f) Normal Operating Condition - The Sector Gate will be designed to operate for side sluicing with basin at +4.00m and lock level at -0.50m. After which, the gate will fully open in near balanced conditions. Side Sluicing time dwell will be based on approx 10 minutes to fill the lock. To reduce leakage to a minimum each gate will be fitted with rubber seals on the vertical edges and on the bottom. Additional O seals will be provided at the far side to allow side sluicing into the recess, without excess water passing through the far side. The seals will be proven design with on going availability. Seal design life will be > 5 years, excluding mechanical damage. 2

3 Vertical marine quality timber fenders will be provided on the lock face of each gate. Pivot bushes and thrust washers will be in Aluminium bronze with a proven greasing system. Pivot brackets will be robust carbon steel fabrications designed to accommodate the maximum calculated loadings. Horizontal and vertical anchor bolts shall be of the post-tensioned, high tensile steel type. Pivot pins and cylinder pins are to be manufactured from stainless steel to BS 1554 grade 431 S29T or approved equivalent. Pivot bracket bores will incorporate stainless steel sleeves to allow future pivot pin removal. 1.3 Sector Gate Hydraulic System Each gate will be opened and closed by a double acting hydraulic cylinder connected to the gate by a stainless steel pin. The cylinder will be supported on a cylinder bracket and incorporate a two axis cardanic ring arrangement to allow for gate deflection and eliminate detrimental cylinder rod side loads and moments. The cylinder support brackets will be anchored to the concrete piers using high tensile stainless steel anchors. Each gate will be locked in the fully open and closed position by valves within the hydraulic system. An oil hydraulic power unit will be located in a lock control building located between the sector gates. The PU will operate both sector gates using 2 pump/motor units in duty standby mode. The building will also house the electrical distribution panel and main control desk. The building needs windows with a good view of the lock and incoming vessels. The gates will normally be interlocked to ensure only one gate is open at a time. Facility will be provided for manual selection of free flow operation, where both gates are opened 3 hours either side of high tide to allow maximum vessel passage. The sector gates will be controlled from a local control pedestal on the lock side, where a good view of the lock and vessels is achieved. The lock will include navigation lights at each end. Sector Gate position control will be achieved by the use of proportional flow control which will allow accurate control 3

4 throughout the cylinder stroke particularly when the gates are inching in the intelligent sluicing mode and for slow down / speed up at cylinder extents. 1.4 Maintenance Stoplogs Maintenance stoplog grooves will be provided at both ends of the lock for sector gate maintenance. The grooves will be steel lined. Four 1.5m deep steel stoplog panels will be provided for isolation up to +4.0m level. The stoplogs will be raised and lowered in balanced head conditions using permanently connected chains and a mobile crane. 4

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