Methods including applying a photo-activated catalyst to a window, directing an ultraviolet light onto the window, producing a bleach via an oxidation reaction, and breaking down organic compounds located on the window using the bleach are provided. Also provided herein are systems including an ultraviolet light source and a window having a photo-activated catalyst layer.

A method comprises measuring a first external pressure within an annulus formed between a wellbore and a drill string disposed therein, where the first external pressure is measured by a first external pressure sensor. A fluid is pumped through the drill string into the annulus so as to move any cuttings in the annulus above the first external pressure sensor. A first internal pressure is measured within the drill string by a first internal pressure sensor. The first external pressure sensor is disposed between the first internal pressure sensor and a bottom of the wellbore.

A tool is used to inject a rapidly solidifying sealant into and across highly fractured oil and gas wellbore formations when a significant loss circulation zone or event is encountered. A system including the tool allows for application of the sealant to the formation without requiring removal of the drill string from the hole. The tool may have operatively associate with containers storing sealant and or sealant components that are provided downhole from the surface via wireline or the like.

A tool is used to inject a rapidly solidifying sealant into and across highly fractured oil and gas wellbore formations when a significant loss circulation zone or event is encountered. A system including the tool allows for application of the sealant to the formation without requiring removal of the drill string from the hole. The tool may have operatively associate with containers storing sealant and or sealant components that are provided downhole from the surface via wireline or the like.

A polymer composition may include one or more monomeric units, with an internal crosslinker, internal breaker, scale control additive or a combination thereof.

An apparatus includes a tool body having a bore that is aligned with a lengthwise axis and a rotating assembly coupled to the tool body. The rotating assembly includes a turbine wheel that is disposed adjacent to an inner surface of the wall and exposed to the bore. The rotating assembly includes an impeller that is disposed adjacent to an outer surface of the wall in a position corresponding to the turbine wheel. Each of the turbine wheel and impeller has a respective axis of rotation that is transverse to the lengthwise axis. The rotating assembly includes a link rod that couples the turbine wheel to the impeller and is used to transfer mechanical energy generated by the turbine wheel to the impeller. The apparatus is operable by fluid flow through a drill string to increase pressure in a wellbore annulus and enhance transportation of formation cuttings up the annulus.

A well tool for removing metal debris from a well bore has a magnet element, an anti-torque anchor, a debris removal unit, a debris container and a first connecting end for a rotatable well string. The magnet element has a cylinder-shaped housing. The removal unit has a helix-shaped longitudinal guide element arranged on the housing. The anchor is connected to the housing or the guide element such that actuation of the anchor during use will prevent rotation of the housing or the guide element, respectively, relative the well-bore. The container has an opening at the end of the housing. The housing and the guide element are rotatable relative each other, and configured such that metal debris accumulating on the housing during use is guided by the guide element towards the opening of the container when the anchor is actuated and the first connecting end is rotated.

An induction heater removing paraffin deposits from a drill pipe includes an inductor having an external coil heating up the deposits in the pipe, and an internal coil heating up a heating element transmitting heat to a rod, conducting heat to a tip melting the deposits surrounding thereof. The tip encloses a thermistor generating temperature feedback signals corresponding to its temperature, being operatively restricted. The inductor includes a capacitor battery series-connected with the coils forming an LC-circuit having a resonance frequency operatively subjected to changes. Electric current in LC-circuit is generated by an HF inverter, and measured by a current transformer generating current feedback signals. The temperature and current feedback signals are transmitted to a microprocessor executing a program controlling the inverter's frequency, providing a power-efficient operation mode of the heater. The proposed design of the coils and a connector, interconnecting the internal coil with the battery, reduces energy losses.

An induction heater removing paraffin deposits from a drill pipe includes an inductor having an external coil heating up the deposits in the pipe, and an internal coil heating up a heating element transmitting heat to a rod, conducting heat to a tip melting the deposits surrounding thereof. The tip encloses a thermistor generating temperature feedback signals corresponding to its temperature, being operatively restricted. The inductor includes a capacitor battery series-connected with the coils forming an LC-circuit having a resonance frequency operatively subjected to changes. Electric current in LC-circuit is generated by an HF inverter, and measured by a current transformer generating current feedback signals. The temperature and current feedback signals are transmitted to a microprocessor executing a program controlling the inverter's frequency, providing a power-efficient operation mode of the heater. The proposed design of the coils and a connector, interconnecting the internal coil with the battery, reduces energy losses.

The present invention relates to a downhole wireline tool for performing a machining operation, such as milling, in a well having a top, the downhole wireline tool having a longitudinal axis, a first end configured to be connected to a wireline and a second end forming a front of the tool facing away from the wireline along the longitudinal axis, the downhole wireline tool comprising a tool housing, a holding section having projectable parts configured to prevent a part of the downhole wireline tool from moving in a direction towards the top, a machining tool arranged in the front of the tool, and a rotation unit for rotating the machining tool, wherein the downhole wireline tool further comprises an oscillation device having a rotational stationary part being connected with the rotation unit and a rotational part being connected to the machining tool, the oscillation device being configured to provide an oscillating movement of the machining tool by oscillating the rotational part in relation to the rotational stationary part.