Apparatus and methods are described for subsea pipeline servicing, including line-pack testing, physical integrity testing, recovery of damaged sections of pipelines, and product removal from subsea structures. In one embodiment of the invention, a subsea pipeline service skid is provided including at least one sample collection bladder affixed to the skid and in fluid communication with a skid mounted pump dimensioned to pull a sample from the subsea pipeline. In another embodiment, a product removal bladder is provided for removal of the hydrocarbons from a subsea structure.

Subsea pipeline service skid

The present invention is directed to a method for completing the commissioning of a subsea pipeline by purging with a compressed gas to dewater and dry the line wherein the operation is done on the seabed. More specifically, the method is carried out with a subsea vechicle (hereinafter “SV”) that powers pumps located on the seabed or are carried by the SV to inject/remove chemical, dewater, and dry, the pipeline. The present invention may be part of the commissioning of a new or old pipeline or a new portion of a pipeline in which a purging of the line with a compressed gas and drying of the line is required. After commissioning, product flows through the pipeline.

Subsea vehicle assisted pipeline commissioning method

A method of cutting underwater structures which comprises the following steps: a local underwater step including: the anchorage of cutting means in the cutting area, exactly positioned to effect the desired cut, to the structure to be cut; a remotely-controlled step including: the automatic activation and de-activation, from a spot at the surface, of the cutting means and the automatic feed thereof in the cutting direction from a non-interference position through the structure, the cutting means being provided with cutting tools for cutting metallic and non-metallic materials; a local underwater step for recovering the cutting means (T).

Method and device for cutting underwater structures

A diamond wire saw and method provides a frame that includes a clamp that attaches to a target (eg piling, beam, tubular), an elongated toothed rack extending away from the mount and target, and a moving portion that carries the diamond wire and motor drives that advance the moving portion toward the target and along the toothed rack while driving the wire around roller guides

Method of cutting target members using a cutting saw device

The present invention is directed to a pumping skid (40) that may comprise a skid structure (80), a high volume pump (81), a battery of high-pressure pumps (82), a chemical water treating tank (83), a docking plate (88) and a bouyancy compensator (90). More specifically, the skid (40) is carried by a subsea vehicle (hereinafter 'SV') that provides the power to the pumps located on the skid (40) to inject water/chemical, pressurize the water, dewater, and dry, the pipeline. The present invention may be part of the commissioning of a new or old pipeline or a new portion of a pipeline in which a purging of the line with a compressed gas and drying of the line is required. After commissioning, product flows through the pipeline.

Subsea vehicle assisted pumping skid packages

A method for severing and recovering a submerged pipeline is disclosed. The severing and recovering operation may be performed with divers or with a remotely operated vehicle. The deflated lift bag is lowered to the submerged pipeline. The deflated lift bag is positioned under the submerged pipeline and then inflated until a section of the pipeline has been raised off of the sea floor. A cutoff saw is next lowered to the raised section of the pipeline. The cutoff saw is clamped to the pipeline prior to severing the pipeline. The cutoff saw is then removed from the severed pipeline. A recovery head is lowered to the raised end of the severed pipeline. The recovery head is aligned and placed in the raised end of the severed pipeline. The recovery head is activated to establish a gripping relationship with the pipeline. A recovery cable is lowered and connected to the recovery head. The recovery cable is retrieved to recover the recovery head and the pipeline to the water surface.

Method for recovering wet buckled pipe

A recovery head for use in retrieving a submerged pipeline to the water surface. The recovery head includes a center of gravity arm attached to one end of the recovery head by a connecting pin. The center of gravity arm maintains the recovery head in a level orientation to allow divers or an ROV to more easily insert the head into the pipeline. After insertion into the pipeline, the center of gravity arm is removed from the recovery head. With the center of gravity arm removed, the recovery head does not obstruct or interfere with any steps involved in the actual retrieval and securing of the pipeline on the lay barge. The rear portion of the recovery head includes two T-posts which connect to oval links attached to the end of a retrieving cable. The links are such that, when placed over the T-posts and the retrieval cable is pulled to retrieve the pipeline to the surface, the links rotate. In this manner, the links are unable to slip off of the T-posts on the recovery head while the recovery head is being pulled to the water surface.

David A. Gray

Papers

Method for recovering wet buckled pipe

Pipeline recovery head