Pipe connecting system

A pipe connecting system having a first pipe piece and a second pipe piece that extend along a longitudinal axis, comprising:

• a clamp configured to connect the first and the second pipe piece to one another and to prevent the first pipe piece and the second pipe piece from moving away from one another along the longitudinal axis,
• a retaining ring being provided that is attached to the second pipe piece by a sealing connection, and on which a first sealing ring that runs around the longitudinal axis is mounted, wherein the retaining ring has an inward-facing circumferential groove in which the first sealing ring is accommodated so that the sealing connection between the first sealing ring and a circumferential first sealing surface is formed,
• wherein the circumferential first sealing surface extends along the longitudinal axis and against which the first sealing ring lies being provided on the first pipe piece, and wherein the retaining ring is connected fixedly to the second pipe piece,
• an interior of the first and of the second pipe piece between the first pipe piece and the second pipe piece being sealed against a surrounding environment by the sealing connection and the lying of the first sealing ring against the first sealing surface,
• when a first clamping surface on the first pipe piece and a second clamping surface on the second pipe piece lie against the clamp, an open space being formed between a first end surface formed on a first stop element that is connected fixedly to the first pipe piece and a second end surface formed on the retaining ring, and the first and second pipe pieces being able to move towards one another without the first sealing ring moving out of contact with the first sealing surface, wherein the open space is disposed entirely above the first pipe piece, and
• the first sealing surface being provided on the outer side, oriented away from the longitudinal axis, of the first pipe piece.