Thursday, July 22, 2010

ANSI AGMA 6032 Standard for Marine Gear Units: Rating

Update: The new standard is ANSI/AGMA 6032-B13 Standard for Marine Gear Units: Rating and Application for Spur and Helical Gear Teeth

Members of the AGMA Helical Enclosed Drives Marine Units Committee are currently revising ANSI/AGMA 6032-A94

This committee evaluates the design, rating and application of enclosed drives in which helical gears are the principal form for propulsion and/or ship service generator sets. If you would like to become involved with the valuable work of the AGMA Helical Enclosed Drives Marine Units Technical Committee, email or call AGMA Headquarters at (703) 684-0211 for details.

ANSI AGMA 6032-B13 is applicable to marine reduction and reversing gears as follows:
  • marine propulsion reduction gears driven by internal combustion engines or electric motors from 1500 to 20 000 horsepower (1120 to 14 900kW) per prime mover, when the rotor speeds do not exceed 3600 rpm.
  • marine propulsion reduction gears driven by steam or gas turbine from 1500 to 30 000 horsepower (1120 to 22 370 kW) per prime mover.
  • power take--off (PTO) gearing that is integral to the propulsion unit.
  • auxiliary propulsion gears.
  • combination of drives listed above.

The fundamental rating formulas are applicable for rating the pitting resistance and bending strength of external spur, helical, or double helical involute gear teeth. The formulas evaluate gear tooth capacity as influenced by the major factors which affect gear tooth pitting and gear tooth fracture.

This standard also addresses bearings, clutches, lubricating oil systems, shafts and certain aspects of vibrations.

Friday, July 9, 2010

HVAC Software -- New Mobile Apps for iPhone

Carmel Software has developed 12 mobile apps for HVAC calculations that work on the iPhone, iPad and other mobile devices.

HVAC apps for your iPhone

HVAC Quick load takes user input for building type, number of occupants, total area and computes rule of thumb HVAC load requirements for commercial, residential, institutional and industrial buildings. Use the HVAC Duct Sizer application to size an HVAC duct run using the constant friction method. These HVAC apps for your iPhone range in price from $2.99 to $23.99 on the Apple iTunes store.

Textile Standards and the Benefit of an Unmade Bed

There's a standard for nearly everything. To test this idea, I occasionally use the keyword search function on The practical importance of the keyword search is to identify standards early when you are researching standards but you don't know exactly what might be available.

Today an article on BBC news entitled Untidy Beds May Keep Us Healthy claims that new research shows that dust mites can't survive long in an unmade bed. So is there a standard dealing with dust mites? JIS L 1920:2007 Testing methods for efficacy against house dust mite of textiles turns up when using a keyword search for "dust mite".

There are 19 standards for "textile testing" from DIN, ISO, BSI, AS, ONORM and the Chinese standards, GB, and nearly 300 international standards for "fabric". There are close to 700 ISO standards for textiles and leather ICS 59 and many hundreds more textile standards from ASTM International.

Two ANSI accredited standards developers cover textile standards. IICRC, Institute of Inspection, Cleaning and Restoration Certification develops standards in the cleaning, restoration, remediation and inspection industry, primarily involving floor coverings and surfaces of all types, upholstery and fabrics, personal property, and structures. The TCATA, Textile Care Allied Trades Association tackles textile standards development in a related area, safety requirements for commercial laundry and drycleaning equipment.

ASTM International is the administrator of TC38 SC1, SC 24 and SC 20 for ISO activities relating to fabrics and textiles.