... over seamless pipe(API Casing, tubing) which is perforated as per international standards to ensure flow performance, and then ... of tube and retain strength of central tube as much as possible on basis of guarantee of integral area of passage ... to requirement.StandardAPI 5L, API 5CT,GB, etc.PackingContainer or as per customers requirementApplications rangePetroleum, chemical, power, gas, metallurgy, ...