The Improvement Of Transient State Response Perfomance Of A 12V190 Natural Gas Engine For Well Drilling

This paper did researches on a way to improve the transient response performance of a gas engine for drilling well application.In domestic oil drilling industry,diesel engines are usually used to power drilling operation.Fuel consumes the large of total costs and badly causes high energy consumption and bad pollution.With a strong attention on energy saving as well as the weakness of oil drilling industry,a mature reliable natural gas power equipment is especially demanded in steady of the old equipments.Because natural gas engines have well developed and widely applied in many fields,natural gas engines are introduced to power drilling equipments,lowering costs on fuel consumption,reducing emissions and producing benefits for drilling companies.This activity is significantly meaningful.As for the natural gas engines instead of diesel engines,the key issue is if the transient state response can meet the demands of drilling operating conditions.This paper analyzed load characteristic of engines as drilling power,proposed the requirements of transient state response performance of engines in drilling operation,analyzed the transient state response performance of the natural gas engine,did discussions on exhaust gas turbocharging system,air and fuel delivery,ignition advanced angel and others and explained the way to improve the transient state response performance.Depending on facts of 12V190 engines,this research optimized the exhaust gas turbocharging system on the basis of the original natural gas engine,comparatively analyzing the transient state respond characteristic between the three-piece pulse exhaust system and the MPC exhaust system by using GT-power.Basing on the theoretical analysis and simulation results,the research introduced the three-piece pulse exhaust system on the 12V190 natural gas engine for drilling application.Depending on the current existing fuelling technology and considering the properties of 12V190 engines,the research proposed a combined fuel delivery method.The method joints the advantages of the premixed and electrically-controlled fuel injection,achieving a homogeneous air and fuel mixture,a high engine response and lower costs,therefore,it is beneficial for the use on natural gas engines.Using the method of a variable ignition advanced angle and pre-acceleration,this research optimized the engine ignition and engine speed governing.A bench test was performed on the optimized 12V190 gas engine,and its load,speed and load response characteristics were examined.Basing on test results,this research analyzed the effects of variable ignition advanced angle,premixed and electronically controlled fuel delivery on the engine transient state response performance.It was shown that the optimized natural gas engine could achieve a transient state response satisfying demands of drilling power.Finally,the 12V190 natural gas engine was tested on drilling sites.Chasing tests in three oil wells verified that this natural gas had a transient state response meeting the demands of oil well operation.Measured results approved that the application of natural gas engines as drilling power was economic and environmentally-friendly.The optimized 12V190 natural gas engine acting as drilling power instead of the diesel engines are qualified for application and population.