Successful modernization of cold pilger mill


From on-site inspection to service report and revamp during regular shutdown

SMS group Technical Service has now realized a major modernization project with a China-based operator of a cold pilger mill – the KPW 25 VMR. The machine was upgraded to an “as new” condition within a very short period of time and has now an increased availability and meets current safety standards.

High availability and efficiency of the plants are a basic requirement for competitiveness in metal processing. Regular inspections and maintenance measures form the basis for safeguarding plant efficiency. To ensure that weak points are detected at an early stage, SMS group has developed machine-specific equipment checks.

First step: On-site inspection

After more than a quarter of a century of operation of one of the cold pilger mills supplied by SMS group, the customer decided to carry out a basic modernization of the machine with the aim to increase availability and meet the current safety standards. The limited availability of spare parts, especially electrical components, was causing additional challenges.

As a first step, SMS group experts carried out an on-site inspection based on a detailed, machine-specific checklist. During the SMS group equipment check specialized know-how of experienced service staff and engineering experts is combined to develop a tailor-made inspection schedule. A customized checklist ensured the precise assessment of the condition of the cold pilger mill. The aim was to ensure that the maximum potential for improvement was utilized. Based on the results, opportunities for upgrading the existing cold pilger mill according to customer´s requirements in terms of product quality and machine availability were evaluated. SMS group then recommended measures for an overhaul that safeguards the quality and availability of the equipment over the long term.

Comprehensive service report and overhaul concept

All of the inspection work performed was documented in a detailed, clearly structured, and easy-to-understand service report. It included the results of the equipment check at an assembly and component level. The electrical and mechanical equipment inspection showed that the electrical hardware, software, and drives were obsolete, and that many mechanical parts needed to be repaired or replaced.

These results provided the basis for a detailed specific technical concept for the overhaul, including a customized mix of repairs and modernizations. The concept included among others the repair of crankshaft incl. counterweights, connecting rods, bearing unit, brake with brake disc, exchange of hydraulic parts, several parts for further assemblies and a new mill stand. Furthermore, the transmission shaft, the shear pin coupling, and the angular gearbox were replaced with an electrical shaft. In addition, the switch cabinet, control desk with HMI and several drives were exchanged and a Siemens S7 system was employed as control system.

Revamp during regular shutdown

SMS group planned the revamp during a routine plant shutdown period. Since the core parts such as crankshaft and roll assembly were manufactured and quality-checked in Germany, machine capacities in the service workshop in Mönchengladbach had to be planned six months in advance so that they were on site before the start of the shutdown in China. The option of manufacturing and overhauling parts or assemblies in Mönchengladbach is interesting for customers not only in Europe but also in North and South America. Customers located in Asia, on the other hand, are able to have parts supplied by a workshop from SMS group’s worldwide manufacturing network. SMS group has expanded its international workshop, service, and production capacities, ensuring its customers benefit from quick and uncomplicated services wherever they are.

Revamp of the KPW 25 VMR

The machine’s safety and availability have been increased significantly. Our customer is now able to handle orders with even higher quality requirements.

Frank Isken, Project Manager Technical Service, SMS group

In the case of the KPW 25 VMR, the plant technicians dismantled the plant on site and sent core parts and assemblies to Mönchengladbach. The bearings were then renewed, bores repaired, stands reassembled, adjusted accordingly, and quality checked. Following their return shipment and reassembly at the customer, cold commissioning was carried out. While the stands were being reworked in Mönchengladbach, the SMS group service technicians stayed on site to replace the electrical and hydraulic parts and prepare for reassembly and commissioning. Meanwhile, the customer’s production facility runs just like a new plant. “Following the overhaul and modernization, the machine’s safety and availability have been increased significantly. Our customer is now able to handle orders with even higher quality requirements,” says Frank Isken, Project Manager Technical Service, SMS group.

Frank Isken