Tips for Selecting Wire And Cable Insulations for Oil and Gas Facilities
The performance of power, instrumentation, and control cables in the oil and gas industry depends on the properties of cable insulation and jacket. Read this blog to pick the correct insulation for your oil and gas facility. For understanding, environments in the oil and gas facilities are divided into regular, rough, and extreme. Before outlining basic jacket materials, let's focus on NEC and UL rules for cables in the oil and gas industry.
NEC and UL Requirements for Cables in the Oil and Gas Industry
UL "OIL RES I" rating means that the cable means that the oil resistance of a cable has been examined at the temperature of 60°C. The rating "OIL RES II" means that oil resistance has been tested at a higher temperature of 75°C.
NEC describes hazardous areas in articles 500 and 505. Article 505 defines hazardous zones. Zone 0 is under the constant influence of gas or vapor that creates an explosive atmosphere, while Zone 1 is under such influence from time to time, and Zone 2 may be under such influence for only a short time. Article 500 describes division systems according to the probability of an explosion. Class I suggests high explosion potential, while Classes II and III are less. Division 1 means that the blast can occur during normal operations, while Division 2 means that it is unlikely.
Cable insulations for regular industrial conditions
When it comes to oil and gas settings, regular industrial conditions can be defined as indoor locations. The cables used here should be durable and resistant to oil, with a good temperature range. Resistance to flames is also expected, but the scale is optional. Some types of these environments include compressor stations or the interior of oil and gas plants. All general industrial requirements apply. Possible types of insulation for this level of protection are PVC, PVC nylon, and LSZH.
PVC insulation and jacket
This is cheap and versatile insulation suitable for many general applications. It is resistant to sunlight and oil. The scale of the oil resistance may vary. An average temperature range is -40 to 105°C, which is rather limited for an industrial application, but acceptable. The cable is flame-resistant.
PVC nylon insulation
PVC nylon has improved oil resistance compared to regular PVC and a higher continuous operating temperature of 150˚C - 185 ˚C. PVC jackets usually go with PVC nylon insulation.
LSZH Zero-halogen thermoplastic insulation or jacket
Low-smoke zero-halogen jackets are halogen-free materials that do not expose harmful gasses when faced with extremely high temperatures. Other materials at different levels of oil and gas industrial conditions can be customized and made low-smoke zero halogens. The thermoplastic LSZH jacket is resistant to sunlight but is not immune to oil.
Cable insulations for rough oil and gas industrial conditions
Harsh and raw oil and gas conditions can be defined as indoor/outdoor environments. Here, cables are exposed not just to oil but to weather, sunlight, and chemicals of different ranges. Exposure to oil is more prominent compared to regular industrial conditions. Some of the applications like that include gas processing and petroleum facilities.
TPE thermoplastic elastomer insulation or jacket
According to UL, this insulation is suitable for direct burial and passes two levels of oil resistance. It can withhold extremely low temperatures but does not do well if extremely high temperatures. The material has excellent resistance to UV lights. The material is continuous flex, making it perfect for control and instrumentation applications.
Chlorinated Polyethylene (CPE) insulation or jacket
CPE has similar properties to TPE, but it does not possess a continuous flex and is unsuitable for direct burial. However, its chemical resistance is way superior to CPE.
XLPE insulation
Cross-Linked polyethylene is good for high-power applications as it sustains higher voltages. The insulation is resistant to oil, UV, and chemicals, including two levels of UL oil resistance. Cross-linking makes the insulation resistant to high temperatures.
Cable insulations for extreme industrial conditions
Extreme industrial conditions in the oil and gas industry mean exposure to extreme low and high temperatures, radiation, and water, including saltwater. These cables also required increased mechanical protection. For added mechanical protection, armor can be added in addition to insulation.
FEP / Fluorinated Ethylene Propylene insulation or jacket
The insulation has unprecedented resistance to fires, chemicals, oil, and UV. The temperature rating is -200°C to 200°C. The insulation is low smoke zero halogen.
