The Dump Bailer is a tool that we can run on a wireline. It facilitates placing the required cement on top of a bridge plug. The release of a weight bar displaces cement from the bailer sections. The plug can undergo a pressure test 24 hours after the last bailer run, when the cement has …
Thixotropic cement slurry in oil and gas is a system that has the capability to develop a self-supporting gel structure. This structure carries part of the hydrostatic pressure of the cement column, thereby reducing the pressure against the formation. This is significant in a low gradient situation where heavy fluid losses would otherwise be experienced …
Bow-spring casing centralizers are also available in multiple styles, including flexible and rigid, welded and nonweld, single piece, and other. Conventional Bow-Spring Centralizers Conventional bow-spring centralizers are the most common type of centralizers (Fig. 1). Also referred to as imperial bow, this centralizer type offers curved flexible bows that can expand or compress according to …
The American Petroleum Institute -API- has written the specifications & classes for cement that oil and gas companies used in oil-well applications. You can find these specifications in “API Specifications for Materials and Testing for Well Cements”, (API Spec 10). 8 Major API Cement Classes There are eight different API cement classes. Table 1 provides the classes …
The Variable Density – VDL Log in essence is a further refinement of the conventional CBL (Cement Bond Log) by including a full waveform display, presented on the log as ‘a variable intensity’ in shades between black and white, representing maximum and minimum in amplitudes. It is used mainly in the interpretation of the cement-to-formation …
The Cement evaluation tool (CET) uses ultrasonic acoustic pulses from a rotating transducer and measures radially instead of axially. The transmitter emits ultrasonic pulses between 200 and 700 kHz and measures the received ultrasonic waveforms reflected from the internal and external casing interfaces. The rate of decay of the waveforms received indicates the quality of …
Prior to cementing in drilling oil & gas job, laboratory testing must be carried out to ensure that the correct recipe is used considering all of the existing conditions and cementing additive properties (oil well cement properties) according to API Recommended Practise. Testing must be conducted on the actual on-site material to be used. The …
Well cementing plays a very important role in the construction, completion, and abandonment of wells since the cement performs vital functions in supporting the casing and drilling wellhead equipment. The casing cannot perform the functions it is designed for, described elsewhere unless effectively cemented in place. The cement forms an impermeable barrier to the passage …
The complete removal of the mud from the annulus (Mud Conditioning Simple Guide For Better Cementing) and its replacement with a good cement slurry is the major requirement for a good cement job. Cement placement is influenced by: Good cement placement can only be achieved when all parameters are optimally fulfilled. Single Stage Cement Jobs …
The cement evaluation is necessary for determining the zonal isolation and the top of cement. The position of the top of cement can be established in three ways: Comparison of the actual TOC with the intended TOC may give an indication that losses (Check also Mud Losses) (unexpectedly low TOC) or channeling (unexpectedly high TOC) …