Pipe connector having mechanical and fusion connections

A method of forming a connection to a multi-layer composite pipe, the pipe comprising at least one reinforcing layer, or layer of high axial strength, at least one inner thermoplastic layer and at least one outer protective layer, wherein at least the outer protective layer of the composite pipe is cut back in order that circumferential surfaces of the inner thermoplastic layer, and the reinforcing layer, or high axial strength layer, are exposed for connection by a connector comprising:

• (i) a hollow, tubular enclosure adapted to receive the pipe;
• (ii) fusion means adapted to make a fusion connection with the inner thermoplastic layer of the pipe;
• and,
• (iii) axially spaced from the fusion means, mechanical gripping means adapted to grip the reinforcing layer of the pipe;
• the fusion means and mechanical gripping means being disposed within the enclosure and the enclosure being adapted, in use, to apply a constraining force to the mechanical gripping means, the axial strength of the joint being provided more by the mechanical gripping means than said fusion connection.

A connector comprising:

• a hollow, tubular enclosure adapted to receive a multi-layer composite pipe, the tubular enclosure comprising two or more co-operating hollow members;
• fusion means disposed within the enclosure and adapted to make a fusion connection with an inner thermoplastic layer of the pipe;
• mechanical gripping means disposed within the enclosure and axially spaced from the fusion means, the gripping, means being adapted to grip a reinforcing layer of the pipe in response to a radial constraining force applied by the enclosure;
• and
• compression members adapted to fit around the tubular enclosure, the compression members having conical surfaces that cooperate with corresponding ramp surfaces of the enclosure to apply radially inward forces on the mechanical gripping means.

A connector comprising:

• a hollow, tubular enclosure adapted to receive a multi-layer composite pipe;
• fusion means disposed within the enclosure and adapted to make a fusion connection with an inner thermoplastic layer of the pipe;
• and
• mechanical gripping means having a ring, or a series of arcuate segments, provided with helical threads that can be screwed onto a reinforcing layer of a pipe disposed within the enclosure, the mechanical gripping means being axially spaced from the fusion means and being adapted to grip the reinforcing layer of the pipe in response to a radial constraining force applied by the enclosure.

A connector comprising:

• a hollow, tubular enclosure adapted to receive a multi-layer composite pipe;
• sealing means including an adhesive sealing material, the sealing means being disposed within the enclosure and adapted to form an environmental seal with an outer protective layer of the pipe, and wherein the enclosure is adapted, in use, to apply a constraining force to the sealing means;
• fusion means disposed within the enclosure and adapted to make a fusion connection with an inner thermoplastic layer of the pipe;
• and
• mechanical gripping means disposed within the enclosure and axially spaced from the fusion means, the gripping means being adapted to grip a reinforcing layer of the pipe in response to a radial constraining force applied by the enclosure.

A connector comprising:

• a hollow, tubular enclosure adapted to receive a multi-layer composite pipe;
• fusion means disposed within the enclosure and adapted to make a fusion connection with an inner thermoplastic layer of the pipe;
• and
• mechanical gripping means disposed within the enclosure and axially spaced from the fusion means, the gripping means being adapted to grip a reinforcing layer of the pipe in response to a radial constraining force applied by the enclosure, the reinforcing layer and the thermoplastic layer being integrated into a single layer.

A connector comprising:

• a hollow, tubular enclosure adapted to receive a multi-layer composite pipe;
• fusion means disposed within the enclosure and adapted to make a fusion connection with an inner thermoplastic layer of the pipe;
• and
• mechanical gripping means disposed within the enclosure and axially spaced from the fusion means, the gripping means being adapted to grip a reinforcing layer of the pipe in response to a radial constraining force applied by the enclosure, the gripping means and the fusion means being adapted to provide electrical continuity across the fusion connection.

A connector comprising:

• a hollow, tubular enclosure adapted to receive a multi-layer composite pipe;
• fusion means disposed within the enclosure and adapted to make a fusion connection with an inner thermoplastic layer of the pipe, the fusion means including an electrofusion-coil in thermal communication with a layer of fusible thermoplastic polymeric material, the electrofusion coil being adapted to provide electrical continuity across the connection through connection with metal in the a reinforcing layer of the pipe;
• and
• mechanical gripping means disposed within the enclosure and axially spaced from the fusion means, the gripping means being adapted to grip the reinforcing layer of the pipe in response to a radial constraining force applied by the enclosure.