* Electrical steel from China, Japan, Korea, Russia, U.S.
* Duties of 21.6 to 35.9 percent (Adds details of duties)
BRUSSELS, May 13 (Reuters) - The European Union will impose anti-dumping duties from Thursday on imports of a grade of electrical steel from China, Japan, Russia, South Korea and the United States, its second set of measures this year to protect European steel producers.
The European Commission has set tariffs on imports of grain-oriented flat-rolled electrical steel (GOES) following a complaint lodged in June 2014 by the European steel producers association, Eurofer.
The duties, detailed on Wednesday in the official journal of the EU, are provisional, pending the outcome of an investigation due to end in November. Normally such duties would then continue for five years.
Duties of 28.7 percent will cover imports from Chinese companies, including Baosteel and Wuhan Iron and Steel Corp, and of 22.8 percent from South Korea producers such as Posco.
The rate for U.S. producers including AK Steel is 22.0 percent and for Russian firms such as NLMK 21.6 percent.
Japan's JFE Steel Corp will face duties of 34.2 percent and Nippon Steel and Sumitomo Metal Corp and other producers from there 35.9 percent.
The figures are in line with those reported by Reuters last month.
European producers are ArcelorMittal, Stalprodukt , Tata Steel and ThyssenKrupp.
The EU transformer industry has said it is deeply concerned by the prospect of duties.
The Commission said that from early 2003 there was an unprecedented increase in demand for transformers, leading to a corresponding increase in demand and prices of GOES, but that from 2011 that market started to experience a significant drop in consumption.
Imports reached about 45 percent of the market as their average price dropped by some 30 percent from 2011 to 2014.
The Commission in March imposed anti-dumping duties on imports from China and Taiwan of cold-rolled flat stainless steel and last month opened an investigation into alleged dumping by Chinese producers of a grade of steel used to reinforce concrete in Britain and Ireland.
Eurofer is also seeking to prolong existing duties on Chinese imports of wire rod.
GOES is a highly-specialized product used by power producers and distributors to produce transformer cores and is made by only 16 producers worldwide.
Eurofer says dumped imports have damaged EU industry by driving prices to below the costs of production, causing substantial losses.
It said the market share of dumped imports into the EU rose to 47 percent in 2012, worth some 150 million euros, with most from Japan and Russia. (Reporting by Philip Blenkinsop; Editing by Robert-Jan Bartunek and Mark Potter)