Undue dilations and criminal process
Artículo 6. Derecho a un proceso equitativo
IV. Algunas consecuencias deri- deri-vadas de su implementación
10- to 14-week delivery
By PATrICk CroW
december 2014 34 compressortech2
n One of the first C-Series 3516 packages sits in an Ex- terran assembly bay.
elimination, gas processing and plant inlet and residue.
William Sayre, vice president, prod- uct lines and marketing at Exterran, said the company interviewed its cus- tomers and its sales staff to determine the crucial issues surrounding com- pression package purchases.
“For a significant number of our cus- tomers, speed of delivery was critical to their operations,” Sayre said. “We also found that many times they had to sacrifice or compromise some of their technical preferences in order to get the packages delivered faster. Our customers would buy available stock packages but say they wished those had certain options that would make them better fits.”
Exterran responded with the C (for configurable) Series, which has the dual goals of flexibility and fast deliv- ery. Sayre said ordering a C-Series package essentially is similar to a consumer ordering a computer on the internet, selecting the basic machine and its key components to fill a par- ticular need.
december 2014 35 compressortech2
www.aciservicesinc.com 740-435-0240
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“This method allows our customers to designate exactly the composition they want and get it manufactured and delivered very quickly,” Sayre said.
Exterran launched the C-Series 3516 last January and formally intro- duced it about a month ago.
“Since January, we’ve experienced higher market demand for this product that we had predicted,” Sayre said. “The reaction has been extremely positive. We’re going strong with the product and have delivered dozens to the field at this point.”
Even if customers don’t necessar- ily need fast delivery, Sayre said the flexibility to customize a package is a major advantage for them, as is the unit’s simple assembly and com- missioning.
“We have competitors who offer many ranges, sizes and configura- tions of compressors and drivers,” he said. “But because of long engine and compressor lead times, they of- ten assemble standard or specula- tive packages that are not tailored to a specific end use. And if they’re
building a customized package, that can take a long time.”
Sayre said Exterran collaborated with the managers of its more than 4 million hp (2980 MW) contract fleet, the largest in the industry, on the design of the C-Series. It has become the new standard package for the fleet.
Some of the options for the C-Series 3516 line include the quiet Harsco/ Air-X-Changers fin fan cooler, Hot- start system and Murphy Centurion Plus control panel.
Standard safety features include automatic shutdown controls and checker-plated, skid-resistant work surfaces. Safety is enhanced be- cause all local instrument gas vents are collected, manifolded and routed to connections at the skid edge. The design facilitates air emissions com- pliance with a catalyst housing and NPT sampling ports.
Selectable safety options include exhaust insulation, caged ladders, and Occupational Safety and Health Admin- istration-compliant work platforms. CT2
C
ustomers are requesting com pressor adaptations due to new or extended process re quirements. Reciprocating compres sors are always tailormade and designed for a specific operating con dition and for long lifetime. New devel opments and requirements or product specifications demand changes in op erating conditions.Thus, it makes sense to verify the existing compressor equipment, to see whether it can be modified or revamped to make the new process conditions or capacity feasible. The procedure to handle revamp business is presented based on a case study.
Introduction
In 2003, Neuman & Esser Group delivered a reciprocating compres sor size 2SZL320H to a refinery in Eastern Europe for a desulfurization
process, compressing hydrogen from 406 psi (28 bar) suction pressure up to 1232 psi (85 bar) discharge pressure.
The reciprocating compressor is a twocrank, horizontal, twocylinder stage, doubleacting, lubricated ser vice machine and 121,000 lb (530 kN) allowable rod load.
The compressor is directly driven by a rigidly coupled electric motor with a nominal driver power of 2280 hp (1700 kW). The original design ca pacity was approximately 1.1 MMcfh (33,000 Nm³/hr).
The NEA scope for the compressor unit as a whole included the pulsation vessels, interstage cooler and inter stage separator up to the last stage check valve. After only five years of successful operation, the hydrogen gas demand increased approximately 15% due to clean fuel requirements.
Initially, the existing reciprocating compressor is recalculated accord ing to the original or asbuilt situation with the compressor design tool KO³ (Compressor Optimization Version 3).
This verifies that the compressor ful fills the designated process conditions without deviations and avoids general mechanical or performance problems. Following this, a calculation is made with new operating conditions.
In a first step, a precheck is made in order to see if an adaptation of the com pressor for the new operating condi tions is possible in principle. The modifi cation of both the compressor itself and the surrounding accessories needs to be considered. If the precheck result is positive, a revamp project is realistic.
Compressor verification
The second step is the detailed veri fication of a compressor revamp as an engineering study. It starts with a ther modynamics and compressor calcula tion by incorporating the specific com pressor details into KO³. In order to be able to run the thermodynamic calcu lation, the gas analysis, suction pres sure, suction temperature, discharge pressure and required capacity must be known for each process or case.
For this case study the conclu sion was to install a new compressor crankshaft with an increased stroke to fulfill customer requirements within the allowable compressor limits. The pis ton rods and piston had to be replaced due to the existing cylinders’ running length. The advantage here is that the cylinders are not changed; the general compressor arrangement can remain.
Each variation in process conditions of compressor properties has an im pact on compressor valves. After the detailed compressor layout calcula tion, the valve design needs to be con firmed. Since the valve dynamics exert a major influence on compressor per formance, valve checking is manda tory to confirm the compressor layout. After the thermodynamics and valves are confirmed, the compressor’s