Crude oil prices are on the rise and many investors are watching the energy sector. However all energy stocks are not created equally. The reality is that while some oil producers may be doing alright, increased competitiveness and the risk over higher taxation and regulation from Washington is separating the winners from the losers.

I watch more than 5,000 publicly traded companies with my Portfolio Grader tool, ranking companies by a number of fundamental and quantitative measures. And this week, seven oil service stocks to sell.

Here they are, in alphabetical order. Each one of these stocks gets a “D” or “F” according to my research, meaning it is a “sell” or “strong sell.”

Cameron International (NYSE:CAM) is a provider of flow equipment products, systems and services. In the last year, CAM stock has dropped 6%, compared to a gain of 7% for the Dow Jones in the same time. Cameron stock gets a “D” grade for operating margin growth, a “D” grade for earnings growth and a “D” grade for the magnitude in which earnings projections have increased over the past months in my Portfolio Grader tool. For more information, view my complete analysis of CAM stock.

Diamond Offshore (NYSE:DO) is an offshore oil and gas drilling contractor, and has experienced a stock loss of 13% since last April. Diamond stock gets an “F” grade for sales growth, a “D” grade for earnings growth and a “D” grade for the magnitude in which earnings projections have increased over the past months in my Portfolio Grader tool. For more information, view my complete analysis of DO stock.

Noble (NYSE:NE) is an offshore drilling contractor for oil and gas companies. In the last year, Noble stock has dropped 16%, compared to gains by the broader markets. NE stock gets an “F” grade for operating margin growth, a “D” grade for its ability to exceed the consensus earnings estimates on Wall Street,  an “F” grade for the magnitude in which earnings projections have increased over the past months, an “F” grade for cash flow and a “D” grade for return on equity in my Portfolio Grader tool. For more information, view my complete analysis of NE stock.

Schlumberger Ltd. (NYSE: SLB) provides oil and gas companies with products and services through every step of their exploration and production. Since last April, Schlumberger stock is down 25%. SLB stock gets a “D” grade for operating margin growth and a “D” grade for the magnitude in which earnings projections have increased over the past months in my Portfolio Grader tool. For more information, view my complete analysis of SLB stock.

Tenaris (NYSE:TS) is involved with the steel pipe manufacturing and distributing businesses. While the broader markets have posted gains in the last year, Tenaris stock has posted a loss of 23%. TS stock gets a quantitative grade of “F” in my Portfolio Grader tool. For more information, view my complete analysis of TS stock.

Transocean (NYSE:RIG) provides offshore contract drilling services for oil and gas wells, and has experiences a loss of 30% in the last 12 months. Transocean stock gets an “F” grade for operating margin growth, an “F” grade for earnings momentum, an “F” grade for its ability to exceed the consensus earnings estimates on Wall Street, a “D” grade for the magnitude in which earnings projections have increased over the past months, an “F” grade for cash flow and an “F” grade for return on equity in my Portfolio Grader tool. For more information, view my complete analysis of RIG stock.

Weatherford International (NYSE:WFT) provides products used for the drilling, evaluation, completion, production and intervention of oil and natural gas wells. WFT stock is down 34% since last April. Weatherford stock gets an “F” grade for its ability to exceed the consensus earnings estimates on Wall Street, a “D” grade for the magnitude in which earnings projections have increased over the past months, a “D” grade for cash flow and a “D” grade for return on equity in my Portfolio Grader tool. For more information, view my complete analysis of WFT stock.

Get more analysis of these picks and other publicly-traded stocks with Louis Navellier’s Portfolio Grader tool, a 100% free stock-rating tool that measures both quantitative buying pressure and eight fundamental factors