GY NMT Nut Screwing Taps

UNC & UNF , Coarse Pitch
As per IS: 6175 Part 5 & DIN 357

Nut Screwing Taps, manufactured in accordance with IS: 6175, are specialized cutting tools designed specifically for the high-production threading of nuts. Unlike standard hand taps, these are engineered to handle the unique stresses of continuous nut tapping, ensuring concentricity and thread accuracy across large batches.

Key Features

  • Extended Lead Chamfer: These taps typically feature a very long lead (chamfer) length, often covering 10 to 15 threads. This distributes the cutting load over many teeth, reducing wear and allowing for smoother entry into the nut blank.
  • Longer Shank: The shank is significantly longer than standard taps. This design allows multiple tapped nuts to collect on the shank during a single operation before they are cleared, making them ideal for use on automatic nut-tapping machines.
  • Material and Hardness: Manufactured from premium High-Speed Steel (HSS), these tools are heat-treated to maintain a high red-hardness, ensuring the cutting edges remain sharp even under the thermal stress of high-speed manufacturing.
  • Thread Profile: Designed for ISO Metric Coarse Threads, ensuring full compatibility with international fastening standards.
TECHNICAL SPECIFICATION FOR COARSE PITCH
Designation d nominal Approximate pitch d1 h9 l L Square a h11 Square l2
1/4 – 20-UNC 6,350 1,270 4,50 32 110 3.55 6
5/16 – 18-UNC 7,938 1,411 6,30 40 125 5 8
3/8 – 16-UNC 9,525 1,588 8 45 140 6.3 9
7/16 – 14-UNC 11,112 1,814 8,0 45 160 6.3 9
1/2 – 13-UNC 12,700 1,584 9,0 50 180 7.1 10
9/16 – 12-UNC 14,288 2,117 11,2 66 200 9 12
5/8 – 11-UNC 15,875 2,309 12,5 63 200 10 13
3/4 – 10-UNC 19,050 2,540 14,0 70 250 11.2 14
7/8 – 9-UNC 22,225 2,822 16,0 80 280 12.5 16
TECHNICAL SPECIFICATION FOR COARSE PITCH
Designation d nominal Approximate pitch d1 h9 l1 L Square a h11 l2
1/4 – 28-UNF 6.35 0.907 4.5 32 110 3.55 6
5/16 – 24-UNF 7.938 1.058 6.3 40 125 5 8
3/8 – 24-UNF 9.525 1.058 8 45 140 6.3 9
7/16 – 20-UNF 11.112 1.27 8 45 160 6.3 9
1/2 – 20-UNF 12.7 1.27 9 50 180 7.1 10
9/16 – 18-UNF 14.288 1.411 11.2 66 200 9 12
5/8 – 18-UNF 15.875 1.411 12.5 63 200 10 13
3/4 – 16-UNF 19.05 1.588 14 70 250 11.2 14
7/8 – 14-UNF 22.225 1.814 16 80 280 12.5 16