Pipes are rolled from coiled strip, passing through a series of forming and finishing processes and quality control functions before being shipped to customers. Efficient tracking throughout manufacturing is essential for quality assurance and for production alignment with customer orders.

Hartlepool production is organized according to a manufacturing schedule that is generated by a centralized planning model. The schedule allocates raw material to specific customer orders, telling the plant which steel coils to load and what pipes to roll, finish, and cut for groups of similar customer orders. Each line in the schedule consists of one or more customer orders. As each individual pipe is cut at the tube mill, it is allocated to a schedule line. The line specifies the finishing requirements for the pipe and therefore effectively dictates its route through the mill.

For all products at the Hartlepool Works, coils of raw material are first made into round pipe in the 500-foot-long forming and welding mill. A continuous length of steel is formed into its circular, nearly-formed state ready for the welding operation which completes the basic pipe. After weld trimming, annealing, cooling, and ultrasonic testing of the weld, the pipe is cold-reduced slightly in diameter and cut to length by a rotary cut-off machine.

Pipes which will become rectangular hollow sections pass to a walking beam reheating furnace and a nine-stand mill where the circumference is slightly reduced and the pipe is hot-rolled into a square or rectangular cross section. Pipes from which threaded oil well casing is to be made also are heat treated and sized to meet the exact physical property requirements demanded on this type of product. Stringent testing and quality checking ensure maintenance of the specified standards.

The System

At the point in the process where welding is completed and pipes are cut to length, the Paperless Factory® System monitors a microprocessor attached to a rotary cut-off machine and, upon notification that a pipe has been cut to length, automatically assigns each pipe to a schedule line (group of similar customer orders). The number assigned and marked on the individual pipe at this cut-off point is recorded by the Paperless Factory® System.

The Paperless Factory® System tracks the movement of every pipe through the welding mill, forming-to-squares process, heat treatment, and tube finishing and testing, ensuring that no pipe is released for shipment until it has satisfied all process specifications in terms of grade, dimensions, finish, and test and certification criteria. The system ensures that each pipe undergoes the necessary process steps and test procedures to meet these requirements. At each routing station, operations are tracked and reported either automatically or manually by a worker scanning the tracking code into the system. Where necessary and appropriate, the system automatically presents on-line work instructions via a CRT device.

The Paperless Factory® System provides on-line, event-driven information to help workers make timely contingency-based routing decisions. For example, if a pipe becomes unusable on a particular line or is scrapped because it has failed a test, the system provides the option to allocate the pipe to another line or scrap it, while suggesting another pipe to make up the order shortfall. Only when a pipe has completed its route and satisfied all of the tests does the Paperless Factory® System call for its shipping release.

The Paperless Factory® System provides a multi-faceted view of the status of all parts of the shop floor. The workers and managers at Hartlepool have on-line access to the status of all parts at a particular operation or in a specific department as well as a queue profile showing, for each specific part, the time of arrival and elapsed time at a position. In addition, on-line status information shows where all pipes of a given schedule line are located. The system at Hartlepool automatically collects production totals for each size and grade of pipe processed at each operation.

In addition to the on-line visibility of shop floor status provided by the Paperless Factory® System, historical information on each individual pipe manufactured is collected and archived. This chronological information details every event that has occurred in the manufacturing process for the pipe. Associated with this process history are any data collected at an operation that describe unique test results, material genealogy, process deviations, employee identifications, and any other relevant information that may be required for future reference.

Results

Controlling work-in-process at Hartlepool was extremely difficult and labor intensive using existing conventional work-in process tracking methods. Hartlepool selected the Paperless Factory® System to respond to its needs for automating existing manual systems through an integrated work-in-process tracking and control system. The Paperless Factory® System electronically controls the movement of work and materials through the factory, eliminating or greatly reducing paperwork and manual data collection. Built around a knowledge base containing order, stock, and manufacturing resource information as well as rules for process flow control, the system collects and manages shop floor data on-line, monitoring events as they occur, and responds with rule-based routing control where necessary. The result is complete visibility of the status of work-in-process in real-time.

The agility of the Paperless Factory® System to maintain product identity and to trace the manufacturing history of every single pipe manufactured, automatically all the way back to the casting of the steel, if necessary, and to identify every pipe originating from the same cast or coil will help achieve this standard of excellence at Hartlepool.

 ©Copyright 1993-1998 Reveille Technology, Inc.