57. Where can exchangers operating pressure be found? {Ans: The nameplate The operating pressure of a heat exchanger can typically be found in its nameplate data. The nameplate is usually attached to the heat exchanger and contains key information such as manufacturer's name, model number, serial number, design temperatures and pressures, test pressure, and sometimes the materials of construction. If the nameplate is not available or readable, the information might also be found in the heat exchanger's original design specifications or in the operations manual provided by the manufacturer.}25. Washers are used to prevent fasteners from marrying? {Ans: surfacewashers are used to prevent the fastener's head or nut from marring the surface of the item being fastened. They distribute the load of a screw or nut evenly over the part being secured, reducing the chance of damage, and they also provide a smooth surface for the nut or bolt to bear against, which can help prevent loosening due to vibration or torque.}26. where are title blocks typically located on a drawing? {Ans: lower rightTitle blocks are typically located in the lower right corner of a drawing or blueprint. They provide important information about the drawing such as