The following information must be known about the materials being
handled:
1. What are the primary chemicals being handled and at what
concentrations?
2. Are there any secondary chemicals, and if so, at what concentration?
3. Are there any tracei mpurities or chemicals?
4. Are there any solids present, and if so, what are their particle sizes
and concentrations?
5. If avessel, will there be agitation and to what degree? If apipeline,
what are the flow rates (maximum and minimum)?
6. What are the fluid purity requirements?
The answers to the aboveq uestions willn arrow the selection to those
materials that are compatible. This next set of questions will narrow the
selectionf urtherb ye liminating materials that do not have the required
physical and/or mechanical properties required.
1. What is the normal operating temperature and temperature range?
2. What peak temperatures can be reached during shutdown, startup,
process upset, etc.?
3. Will any mixing areas exist where exothermic or heat-of-mixing
temperatures can develop?
4. What is the normal operating pressure?
5. What vacuumconditions andrange are possibleduring operation,
startup, shutdown,oru pset conditions?
6. Will there be temperature cycling?
7. What cleaning methods willb eu sed?
Finally,consideration should be given the conditions external to the vessel
or pipe.
1. What are the ambient temperature conditions?
2. What is the maximum surface temperature during operation?
3. What are the insulation requirements?
4. What is the nature of the external environment? This can dictate
finish requirements and/or affect the selectionofthe shell material.
5. What are the external heating requirements?
6. Is grounding necessary?
Sheet Linings
289
CAT8247—CHAPTER 6—6/10/2006—12:28—SRIDHAR—XML MODEL B–pp. 287–402
handled:
1. What are the primary chemicals being handled and at what
concentrations?
2. Are there any secondary chemicals, and if so, at what concentration?
3. Are there any tracei mpurities or chemicals?
4. Are there any solids present, and if so, what are their particle sizes
and concentrations?
5. If avessel, will there be agitation and to what degree? If apipeline,
what are the flow rates (maximum and minimum)?
6. What are the fluid purity requirements?
The answers to the aboveq uestions willn arrow the selection to those
materials that are compatible. This next set of questions will narrow the
selectionf urtherb ye liminating materials that do not have the required
physical and/or mechanical properties required.
1. What is the normal operating temperature and temperature range?
2. What peak temperatures can be reached during shutdown, startup,
process upset, etc.?
3. Will any mixing areas exist where exothermic or heat-of-mixing
temperatures can develop?
4. What is the normal operating pressure?
5. What vacuumconditions andrange are possibleduring operation,
startup, shutdown,oru pset conditions?
6. Will there be temperature cycling?
7. What cleaning methods willb eu sed?
Finally,consideration should be given the conditions external to the vessel
or pipe.
1. What are the ambient temperature conditions?
2. What is the maximum surface temperature during operation?
3. What are the insulation requirements?
4. What is the nature of the external environment? This can dictate
finish requirements and/or affect the selectionofthe shell material.
5. What are the external heating requirements?
6. Is grounding necessary?
Sheet Linings
289
CAT8247—CHAPTER 6—6/10/2006—12:28—SRIDHAR—XML MODEL B–pp. 287–402