AWWA C561 pdf download.Fabricated Stainless Steel Slide Gates
4.4.5.2 Design. Guides shall be integral with the frame or bolted to the frame. Guides, including their bolting, if any, shall be designed to resist the design head indicated and the wedging action, if any, with a safety factor of 4 with regard to ultimate tensile, compressive, and shear strength and a minimum safety factor of 2 with regard to the tensile, compressive, and shear yield strength. The guides shall support at least one half of the slide height when the slide is in full open position. Guides of self-contained gates shall be designed to adequately support the yoke and resist all operating loads with a safety factor of 4 on the ultimate or 2 on the yield with regard to the tensile, compressive, and shear strengths of the material.
4.4.6 Yoke. Self- contained gates shall be provided with a wrought stainless steel yoke designed to withstand the thrust of the actuator when a 40-1b (178-N) effort is placed on the handwheel or crank, with a minimum safety factor of 4 with regard to ultimate tensile, compressive, and shear strength and a minimum safety factor of 2 with regard to the tensile, compressive, and shear yield strength. Yokes for hydraulic cylinders shall meet the above criteria at the output thrust at maximum working pressure (pressure relief valve setting). In addition to the above criteria for manual operation, yokes for electric actuators shall be designed for a safety factor of 1.5 with regard to yield strength at the locked-rotor torque of the actuator. Yoke deflection should not exceed /360 of gate width at maximum operating load. The actuator mounting and guide contact surfaces shall be accurately formed to ensure proper stem alignment. The yoke shall be designed to allow removal of the slide from the gate assembly.
4.4.8 Wedging devices and pressure pads. Adjustable wedges or pressure pads shall be provided to ensure seat contact when the gate is fully closed, for gates with seats that are not self- adjusting, when deemed necessary y by the gate manufacturer to meet the specified leakage. The mating surfaces of these devices shall be accurately made and of sufcient contact area to assure proper operation. Adjusting mechanisms shall be so designed as to remain securely in place after adjustment.AWWA C561 pdf download.