DIN934 black nut vs. JIS B 1181 before year 1964: similarities and differences

In the industry and construction industry Bolt heads are considered very important fastening equipment. But in Thailand, many people may wonder between What is the difference between a "white zinc plated metric black nut (DIN934)" and a "white metric nut (JIS B 1181: 1964)"? Because from the appearance they look the same. Today we will answer the question.


Different production standards:

• "Black metrics white zinc plated nut" produced according to German standard DIN934 or Japanese standard JIS B 1181 (after 1964 until the present year)
  
• It is commonly used in industries all over the world.
  
• White zinc plated metrics nut manufactured according to JIS B 1181 (before year 1964)
  
• It's an old Japanese standard.
  
• It is still used in some industries.

 

Important Physical Differences

1. Thread Pitch

• Black metrics white zinc plated nut: has standard thread pitch according to DIN934.
  
• White metrics nut: Has a different thread pitch according to the old JIS standard.
  
• This difference may affect compatibility with other screws or nuts.
  
  

2. Size of Across Flat (AF) of the nut

• In some sizes, the two types of nut heads have different Across Flat (AF) sizes.
  
• Affects the choice of wrench or tool for tightening, such as a pneumatic block.
  

To consider in choosing to use:

• Compatibility with other devices. Check the standards of the devices that will be used together.
• Consider the appropriate thread pitch.
• To check the size of wrench is required.
• Prepare tools appropriate to the bolt head size.

       However, the division of "black metrics, white zinc plated nut" and "white zinc plated metrics nut" is based on the familiarity of technicians in Thailand only. Cannot use this blog to be translated into other languages.