The ratings of nine machinery stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Hyster-Yale Materials Handling, Inc. Class A (HY) ratings are on the decline this week as the company earns an F (“strong sell”). Last week, it received a D (“sell”). In Portfolio Grader’s specific subcategories of Earnings Revisions and Earnings Surprise, HY also gets F’s. Shares of the stock are being traded at a very rapid pace, up 923.9% from the week prior. To get an in-depth look at HY, get Portfolio Grader’s complete analysis of HY stock.

Trinity Industries, Inc.’s (TRN) rating falls to a D (“sell”) this week, down from C (“hold”) the week prior. Trinity Industries is engaged in the manufacture and sale of railcars and railcar parts, inland barges, structural wind towers, concrete and aggregates, asphalt, highway products and structural steel components. The stock also gets an F in Earnings Momentum. As of Feb. 27, 2015, 12.5% of outstanding Trinity Industries, Inc. shares were held short. Trade volume is up 432.3% from the previous week. For more information, get Portfolio Grader’s complete analysis of TRN stock.

American Railcar Industries, Inc. (ARII) gets weaker ratings this week as last week’s C drops to a D. American Railcar Industries designs, manufactures, and sells hopper and tank railcars in North America. The stock gets F’s in Cash Flow and Sales Growth. Shares of the stock have been changing hands at an unusually rapid pace, four times the rate of the week prior. To get an in-depth look at ARII, get Portfolio Grader’s complete analysis of ARII stock.

Manitowoc Company, Inc. (MTW) earns an F this week, moving down from last week’s grade of D. Manitowoc is a diversified industrial manufacturer of cranes and related products and food service equipment. The stock gets F’s in Earnings Revisions and Earnings Surprise. Shares of the stock have been trading at an exceptionally rapid pace, up fourfold from the week prior. For more information, get Portfolio Grader’s complete analysis of MTW stock.

This week, Watts Water Technologies, Inc. Class A (WTS) drops from a C to a D rating. Watts Water Technologies designs, manufactures and sells a line of water safety and flow control products for the water quality, water conservation, water safety and water flow control markets. The stock gets F’s in Earnings Revisions and Earnings Surprise. The stock has a trailing PE Ratio of 39.50. To get an in-depth look at WTS, get Portfolio Grader’s complete analysis of WTS stock.

Slipping from a D to an F rating, Kaydon Corporation (KDN) takes a hit this week. Kaydon designs, manufactures, and sells custom-engineered products for a variety of industries, including aerospace, defense, and industrial. The stock gets F’s in Earnings Growth, Earnings Momentum, Cash Flow and Margin Growth. The stock’s trailing PE Ratio is 37.20. For more information, get Portfolio Grader’s complete analysis of KDN stock.

This week, Sun Hydraulics Corporation’s (SNHY) rating worsens to a D from the company’s C rating a week ago. Sun Hydraulics designs and manufactures high-performance screw-in hydraulic cartridge valves and manifolds, which control force, speed and motion as integral components in fluid power systems. Shares of the stock have been changing hands at an unusually rapid pace, up 6167.2% from the week prior. To get an in-depth look at SNHY, get Portfolio Grader’s complete analysis of SNHY stock.

The rating of Dover Corporation (DOV) declines this week from a C to a D. Dover owns and operates a global portfolio of manufacturing companies that provide components and equipment, specialty systems and support services in the industrial products, engineered systems, fluid management and electronic technologies markets. Shares of the stock have been trading at an exceptionally rapid pace, up threefold from the week prior. For more information, get Portfolio Grader’s complete analysis of DOV stock.

This is a rough week for CIRCOR International, Inc. (CIR). The company’s rating falls to F from the previous week’s D. CIRCOR designs, manufactures, and markets highly-engineered products, such as valves, that control the flow of fluids safely and efficiently in the energy, aerospace, and industrial markets. The stock gets F’s in Earnings Revisions and Sales Growth. Shares of the stock have been changing hands at an unusually rapid pace, twice the rate of the week prior. To get an in-depth look at CIR, get Portfolio Grader’s complete analysis of CIR stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.