According to the terms of reference (Annex 1 to the contract per lot), the subject of this tender is to carry out regular inspection and cleaning of the pipelines in the entire ONTRAS pipeline network in the following lots:

Los 1: Inspektionsmolchungen (I-Molchung)

The 2: Reinigungsmolchungen (R-Molchung)

To this end, a framework agreement is to be concluded with several economic operators. The contract begins on 01.07.2024, with the enquiries/individual calls being made in 2024. The first actual pigging services are scheduled to start from 01.01.2025.

ONTRAS Gastransport GmbH, hereinafter referred to as ONTRAS or Client (AG), is a supra-regional gas transmission system operator in the European interconnected system and must maintain its pipeline network in such a way that technical safety is guaranteed. For this purpose, regular inspections of the pipelines are required in accordance with Section 5 DVGW Worksheet G 466-1, for which the AG is planning to award a framework contract for the pigging services with several contractors in Lot 1 - Inspection Pigging. These inspections are to be carried out as inspection pigs in accordance with the terms of reference, which are issued in the draft stage with the contract notice (final version is sent with an invitation to tender). These inspections are used to identify abnormalities in the pipe system of the pipeline network and to assess the technical integrity of the pipeline system. The abnormalities to be detected include, for example: internal and external wall thickness removals, pitting corrosion, furrows, dents, bubbles, laminations, crack-like anomalies, etc.

In the ONTRAS network, about 4,000 km of pipelines are technically piggable. The dimensions of the pipelines are between DN 300 and DN 1100 with wall thicknesses of approx. 6 mm to approx. 20 mm. The pipelines are operated at a pressure of 25 bar to 100 bar.

ONTRAS Gastransport GmbH, hereinafter referred to as ONTRAS or Client (AG), is a supra-regional gas transmission system operator in the European interconnected system and must maintain its pipeline network in such a way that technical safety is guaranteed. For this purpose, according to Section 5 DVGW Worksheet G 466-1, regular inspections of the pipes are required, which are carried out as inspection pigging. The subject of the invitation to tender in Lot 2 is the cleaning services required for this purpose, as cleaning pigs, which are necessary to achieve the required degree of cleaning inside the pipes in preparation for the inspection pigging. For this purpose, the AG plans to award a framework contract for these pigging services to several contractors. The specific scope of services for the cleaning services is described in the service description, which is issued in the draft stage with the contract announcement (final version is sent with an invitation to tender).

In the ONTRAS network, about 4,000 km of pipelines are technically piggable. The dimensions of the pipelines are between DN 300 and DN 1100.