Toploading Oven for Downhole Tool Calibration
Despatch PTC ovens are specially designed for downhole drilling tools. Burn-in testing is done to make sure the electronics can operate accurately at elevated temperatures. In the field, these ovens are used for periodic calibration of the electronics on the drill tool. PTC ovens are designed with fans and controls located below the work chamber to minimize floor space, which is at a premium in the field offices where the ovens are most commonly used. The PTC offer consistent, repeatable performance in a small package. A rugged design allows for long term reliability and all units are low maintenance. Removable ends allow multiple units to be connected for use with longer tools.
Downhole drilling tools perform many functions.
Video Inspections provide a continuous, permanent visual record of the well casing, screen, or open hole. A video camera built into a waterproof stainless-steel housing is lowered into the well via a triple-armored coaxial cable. The image is transmitted back via the cable to a VHS recorder and monitor at the surface. This arrangement provides a permanent videotape recording, as well as real-time viewing, which facilitates detailed inspections of features of interest.
Geophysical Logging (sometimes erroneously called “electric logging”) is a generic term encompassing a wide variety of techniques. Simply put, geophysical logging is the measurement of various physical parameters by the lowering of a probe or sonde containing sensors into a well or borehole. These parameters can then be used to evaluate the geology and well construction.
Natural Gamma Ray Logging is done by measuring the amount of emitted gamma radiation as a function of depth so we can paint an accurate “picture” of the nature of the material penetrated by the well. Electric Logging uses the marked differences in electrical properties between fine-grained sediments (shale, clay and silt) and coarser-grained material (sandstone, sand and gravel), to identify stratigraphic units from logs of electrical resistivity and natural electric potentials. Caliper Logging is simply a record of the changes in hole diameter with depth.
Despatch’s unique chamber size and force-convected airflow provide uniform heat over the length of the tool. Multiple ovens can be connected end-to-end to accommodate any required length. The marinite end caps can be machined to insert instruments or tooling. A digital, three-mode PID control allows precise temperature control while a separate high-limit control with manual reset provides over-temperature protection. Designed with silicone door seals and positive-latching clamps to hold the door securely in place, the PTC ovens are also provided with a dolly for easy moving.
We offer two standard top-loading sizes and can build to special requirements including a front-loading design. We also offer a non-magnetic, non-metallic version.