55° Metric 60° Thread Pitch Cutting Screw Pitch Gauge Tool Stainless Steel Metric Screw Thread Gauge

1. 55° Imperial Thread Gauge (Whitworth Thread Form)

• Thread Form: This gauge checks threads with a 55-degree thread angle and rounded roots and crests.

• Common Types:

• BSW (British Standard Whitworth): The original imperial thread.

• BSF (British Standard Fine): A fine-pitch version of BSW.

• BSP (British Standard Pipe): The standard for pipe threads in many regions. BSPP (parallel) and BSPT (tapered) threads both use the 55° form.

• Identification: These are identified by the thread type (e.g., BSW, BSPT) and the nominal size in inches (e.g., 1/4", 1/2").

2. 60° Metric Thread Gauge (ISO Metric Thread Form)

• Thread Form: This gauge checks threads with a 60-degree thread angle and flat or rounded roots and crests.

• Common Types:

• M (ISO Metric): The global standard for general engineering. Includes coarse (M8) and fine (M8x1) pitch series.

• UN/UNF (Unified National): Although an inch-based system, it also uses a 60° form. It is the standard in the United States.

• Identification: Metric threads are identified by the letter 'M', the nominal diameter in mm, and the pitch in mm (e.g., M8x1.25).

Gauging Method: Go/No-Go Principle

Both types of thread gauges typically come in a double-ended set for efficient inspection:

• GO Gauge (marked with "T" or "GO"): This end checks the maximum material condition (the largest the external thread can be). A good thread must accept the GO gauge freely over the full length of the thread.

• NO-GO Gauge (marked with "Z" or "NO GO"): This end checks the minimum material condition (the smallest the external thread can be). A good thread must not allow the NO-GO gauge to screw on by more than two turns.

A thread is considered acceptable only if it passes both tests.

Applications

These gauges are vital for quality assurance in various industries, including:

• Automotive and Aerospace

• Fluid Power and Plumbing (especially BSP threads)

• General Machinery and Equipment Repair

• Manufacturing and Assembly

  
  

Specification:

Product Name: Thread gauge

Model：20set 60° Metric/55° Inch

Applicable Scenarios 1：Threaded Measures

Applicable Scenarios 2：Bore Gauge Measuring Tools

Applicable Scenarios 3：Hand Tool Measuring Tools

Applicable Scenarios 4：Woodworking Tools Gauge

Package Included:

1PCS Thread gauge

（Specification: 20set 60° Metric/55° Inch）

Feature:

1. Clear specification scale on the surface of the ruler piece

2. Ruler body is forged by CR stainless steel.

3. The surface is polished and chrome-plated, with strong anti-rust ability.