Case Study

Identifying Workmanship Issues with Factory Grade® Technology

Contractor Workmanship Feedback with IMCORP Factory Grade® Technology

OVERVIEW
Workmanship issues are identified with the Factory Grade® technology.
CHALLENGE
Identifying root cause of substandard performance of joints in an efficient and effective manner.
RESULTS
Utility client partners with IMCORP to ensure quality and educate installers on how to identify defects with immediate evidence-based feedback before failure.

A utility requested IMCORP to commission a 750kcmil cable system at a new upscale subdivision as part of their medium voltage quality control program. Initial assessment with our Factory Grade® technology pinpointed 2 pre-molded joints on 2 phases that did not meet the accessory manufacturer’s minimum performance standards. The first and second repair attempts by the original contractor crew were assessed only to find joints still failing to meet minimum performance standards. The installation contractor started questioning the validity of the assessment. The utility client was also under pressure from the developer of the residential subdivision to energize the circuit. Our client’s construction supervisor requested our assistance with a field dissection and root cause analysis with the installation contractor in attendance.
 
Working with the manufacturer, installation contractor, and the utility client’s engineer and construction supervisor, we directed the disassembly of the joints and identified several installation workmanship issues including, insufficient void filling grease, non-radial semicon cutbacks, insufficient connector crimping, improper application of the end caps, and an extreme bending radius near one of the joints.  The workmanship issues were corrected and the joints were re-assembled. Our Factory Grade® technology then verified the entire cable system met the manufacturer’s performance standards. This case is yet another example of IMCORP partnering with utility clients to ensure quality and educate installers on how to identify defects with immediate evidence-based feedback before failure.
Figure 1: Field disassembly of the premolded joints showed non-radial and jagged cutbacks (left) creating stress-enhancements. Evidence of insufficient void filling grease applied under the end caps on both sides of the joint body (right, yellow circle), creating large air voids between the two mating surfaces

LEADERSHIP

THE STANDARD IN POWER CABLE RELIABILITY