Air motor assembly

Abstract

An air motor apparatus for air drilling includes a filter assembly at an uphole end that receives compressed air and diverts a constant pressure portion through a filter to a vane motor and a remaining portion to an air hammer at a downhole end via bypass conduits. The apparatus includes one or more sensors for measuring drilling conditions, the sensors being connected to a communication device capable of transmitting the sensor data to the surface. The sensors and their wiring are shielded from high air speeds by bypass conduits and components of the filter assembly.

What is claimed is: 
     
         1 . An apparatus comprising:
 a tubular housing comprising an inlet at an uphole end configured to receive pressurized air and an outlet at a downhole end;   a filter housing within the tubular housing;   a filter positioned within the filter housing and configured to receive a first portion of the pressurized air via a filter inlet of the filter housing;   a communication device within the filter housing;   a vane motor downhole of the filter and configured to receive the first portion of the pressurized air from the filter;   an air bypass conduit positioned about the vane motor and configured to direct a second portion of the pressurized air past the vane motor;   a sensor positioned downhole of the filter; and   wiring connecting the sensor to the communication device, wherein the wiring is isolated from the second portion of the pressurized air by the air bypass conduit.   
     
     
         2 . The apparatus of  claim 1 , further comprising a motor canister positioned about the vane motor;
 wherein the air bypass conduit is formed between the tubular housing and the motor canister; and   wherein the wiring is disposed at least partially within the motor canister.   
     
     
         3 . The apparatus of  claim 2 , wherein the motor canister comprises a valve configured to exhaust air from the vane motor out of the tubular housing. 
     
     
         4 . The apparatus of  claim 1 , wherein the air bypass conduit comprises a plurality of tubes and wherein the wiring is disposed at least partially within interstices between the plurality of tubes. 
     
     
         5 . The apparatus of  claim 1 , wherein the communication device is a wireless communication device. 
     
     
         6 . The apparatus of  claim 5 , wherein an upstream end of the filter housing comprises a material through which a signal from the wireless communication device can pass. 
     
     
         7 . The apparatus of  claim 5 , wherein the wireless communication device comprises a microwave transmitter and an upstream end of the filter housing comprises a material that is transparent to microwaves. 
     
     
         8 . The apparatus of  claim 1 , wherein the sensor is a gyroscope. 
     
     
         9 . The apparatus of  claim 1 , wherein the sensor is a pressure sensor. 
     
     
         10 . The apparatus of  claim 1 , further comprising a gas detection system comprising a gas sampling chamber and a gas sensor within the gas sampling chamber;
 wherein the tubular housing comprises a port in fluid communication with the gas detection system, the port being configured to introduce a sample gas from an exterior of the tubular housing into the gas sampling chamber;   wherein the gas sensor is in communication with the communication device; and   wherein the gas detection system is at least partially isolated from the second portion of the pressurized air by the air bypass conduit.   
     
     
         11 . The apparatus of  claim 10 , wherein the gas sensor is configured to detect combustible gases, H 2 S gas, or a combination thereof. 
     
     
         12 . The apparatus of  claim 10 , wherein the gas detection system comprises a venturi nozzle configured receive air from the first portion of the pressurized air and create a vacuum to draw the sample gas through the port and into the gas sampling chamber. 
     
     
         13 . A system comprising:
 the apparatus of  claim 1 ,   an air compressor configured to generate and deliver the pressurized air to the inlet of the apparatus; and   an air hammer connected to the outlet of the apparatus; and   wherein the apparatus is configured to direct the second portion of the pressurized air to the air hammer.   
     
     
         14 . The system of  claim 13 , wherein the second portion of the pressurized air drives an axial motion of the air hammer, and the first portion of the pressurized air drives a rotational motion of the air hammer via the vane motor. 
     
     
         15 . The system of  claim 14 , wherein the apparatus comprises a regulator configured to maintain a constant pressure of the first portion of the pressurized air. 
     
     
         16 . The system of  claim 13 , further comprising a drill string connected to the uphole end of the apparatus. 
     
     
         17 . A method, comprising:
 directing pressurized air to an apparatus positioned within a borehole;   driving a vane motor with a first portion of the pressurized air;   using a sensor, measuring an operational parameter of the apparatus;   transmitting data related to the operational parameter from the sensor to a communication device positioned uphole of the sensor; and   using the communication device, wirelessly transmitting the data to a receiver positioned uphole of the communication device.   
     
     
         18 . The method of  claim 17 , further comprising:
 diverting a second portion of the pressurized air through an air bypass conduit past the vane motor;   wherein transmitting the data comprises using wiring connecting the sensor to the communication device; and   wherein the wiring is isolated from the second portion of the pressurized air via the air bypass conduit.   
     
     
         19 . The method of  claim 17 , wherein the sensor comprises a speed sensor, a gas sensor, or a gyroscope. 
     
     
         20 . The method of  claim 18 , further comprising:
 directing the second portion of the pressurized air to an air hammer downhole of the vane motor;   driving an axial motion of the air hammer with the second portion of the pressurized air; and   driving a rotational motion of the air hammer via the vane motor.