Failure exchanger tube

A 1-ft. (30-cm)-long section of steel heat exchanger tubing containing no failure was received. The section was submitted for evaluation of the internal surface, which was lined with a phenolic epoxy resin. 

Remote contingencies such as heat exchanger tube failure or in case of closure of a CSO valve. 

In production facility design, the most common relieving conditions are (1) blocked discharge, (2) gas blowby, (3) regulator failure, (4) fire. (5) thermal, and (6) heat exchanger tube rupture. Relief valve design How rates are commonly determined as follows. 

Equipment Failure pumps, tubes in heat exchangers and furnaces, turbine drivers and governor, compressor cylinder valves are examples of equipment which might fail and cause overpressure in the process. If an exchanger tube splits or develops a leak, high pressure fluid will enter the low side, overpressuring either the shell or the channels and associated system as the case may be. 

The presence of trace quantities of mercury in a process stream can cause the catastrophic failure of brass heat-exchanger tubes, from the formation of a mercury-copper amalgam. Incidents have occurred where the contamination has come from unsuspected sources, such as the failure of mercury-in-steel thermometers. 

Premature failure of exchanger tubes can occur through vibrations induced by the shell-side fluid flow. Care must be taken in the mechanical design of large exchangers where... 

Failure of Heat Exchanger Tubes If a heat exchanger shell rating is less than the pressure level of the circulating medium and an internal heat exchanging tube ruptures or leaks it will overpressure the vessel. 

TEMPERATURE HIGH Ambient Conditions Fouled or Failed Exchanger Tubes Fire Situation Cooling Water Failure Defective Control Valve Heater Control Failure Internal Fires Reaction Control Failures Heating Medium Leak into Process Faulty Instrumentation and Control... 

Electric power loss Accumulation of noncondensibles Failure of automatic controls Loss of heat in series fractionation Volatile material entering system Heat exchanger tube failure... 

Rear-End Heads. Shells and tubes are exposed to different temperatures in operation, resulting in thermal stresses that can cause bending, buckling, or fracture of the tubes or shell or failure of tube-to-tubesheet joints. This thermal stress problem can be further compounded if the shell and tube materials are different, or residual stresses remain after the exchanger fabrication. Proper rear head design can minimize/eliminate these thermal stresses, and the specific design depends upon the thermal stresses in the operation. 

Failure of exchanger tube. A common practice (9) is to set the relief requirement to allow for steam or heating fluid entering from twice the cross sectional area of one tube. 

Refractory lining failure Acid piping and cooler leakages Corrosion of demister pads/failure of candle demisters Heat exchanger tube leakages Loss of catalyst activity... 

In a number of cases, heat exchanger tube failures attributed to flow-induced vibration have resulted In consequential damage to other equipment within a plant. Failures of this nature have proven to be the most destructive, most costly, and have required the longest plant shutdowns for rectification. 

Heat Exchanger Valve Failures or Heat Exchanger Tube Leaks... 

---