Threading

According to international standards and regional application habits, there are various types of pipe threads, each with its own characteristics and applicable scenarios. We can process various standard threads according to customer needs to meet the connection requirements of different regions and projects. The common pipe thread types are as follows:

1. NPT or NPS (National Pipe Tapered or Straight) 
NPT (National Pipe Tapered) is a tapered pipe thread, and NPS (National Pipe Straight) is a straight pipe thread. Both are the most common thread types in North America, widely used in North American industrial pipelines, water supply and drainage systems, and mechanical equipment connections. They have good sealing performance and strong applicability.

2. MIP or FIP (Male or Female Iron Pipe) 
MIP refers to male iron pipe threads, and FIP refers to female iron pipe threads. Their thread dimensions are the same as NPT threads, which can be compatible with NPT threaded fittings. They are often used in the connection of iron pipes and metal fittings, and are widely used in construction and industrial fields.

3. BSP(T) or BSP(S) (British Standard Pipe Tapered or Straight) 
BSP(T) is a British standard tapered pipe thread, and BSP(S) is a British standard straight pipe thread. They are the most common thread types in Europe and most Commonwealth countries, and are widely used in European industrial pipelines, chemical equipment and water conservancy projects. Their structural design is reasonable and the connection is firm.

4. Compression 
Compression thread is a unique threaded fitting, which has a special structural design and cannot be mated with other thread types. It is mainly used in scenarios that require high sealing performance, such as gas pipelines and high-pressure water supply pipelines, and has the advantages of convenient installation and reliable sealing.

5. UNS (National Unified Special)
UNS is a national unified special thread in the United States, which has special thread dimensions and specifications. Some UNS threads are compatible with compression fittings, and are often used in special equipment and precision mechanical connections that require high precision and special size requirements.

The quality of pipe threads is directly related to the connection effect and service life. To ensure the precision of threading, we need to clearly understand the composition parts of pipe threads and strictly control each parameter during processing. The main parts of pipe threads are as follows:

1. Thread Dimension 
The thread dimension refers to the major diameter or outside measurement of the thread, which is the key parameter to determine the compatibility of the thread with the fitting. We strictly control the thread dimension according to international standards and customer requirements to ensure that the thread can be perfectly matched with the corresponding fitting.

2. Pitch
The pitch is the distance from the peak of one crest to the peak of another adjacent crest on the thread. It is an important parameter affecting the tightness and connection strength of the thread. Different thread types have different standard pitches, and we accurately control the pitch during processing to avoid thread sliding or loose connection.

3. Thread Angle
The thread angle is the angle between the two side surfaces of the thread (i.e., the angle of the valley between the two peaks). It directly affects the stress distribution and bearing capacity of the thread. We strictly follow the standard thread angle for processing to ensure that the thread has good load-bearing performance and service life.

Our threading processing adheres to strict standardized procedures, with advanced equipment and precise operation, ensuring the accuracy, consistency and quality stability of each thread. The specific processing steps are as follows:
1. Pre-Processing Preparation: First, inspect the steel pipes to be threaded (including seamless steel pipes, stainless steel pipes, alloy steel pipes, OCTG, etc.), confirm the material, specifications, and thread type requirements, and select the appropriate threading equipment and tools. Remove rust, oil stains, burrs and other impurities on the pipe end to avoid affecting the threading effect and thread quality.
2. Workpiece Fixing: Fix the inspected and treated steel pipe on the high-precision CNC threading machine using a vise, clamp and other fixing tools, adjust the position to align with the processing center, and ensure that the pipe does not shift or shake during processing, so as to ensure the accuracy of the thread.
3. Equipment Debugging and Parameter Setting: Debug the CNC threading machine, set the thread type, thread dimension, pitch, thread angle and other parameters according to the project requirements and international standards, and test-run the equipment to ensure the normal operation of the equipment and the accuracy of the parameters.
4. Threading Execution: Start the threading equipment to perform threading processing. During the processing, the closed-loop detection system is used to monitor the processing process in real time, adjust the parameters in time if there is any deviation, and ensure that the thread surface is smooth, the tooth shape is uniform, and there is no thread damage or uneven tooth shape.
5. Post-Processing Inspection: After the threading is completed, stop the equipment, take down the workpiece, and conduct a comprehensive inspection of the thread (including thread dimension, pitch, thread angle, surface roughness, etc.). Use professional detection tools to verify the thread accuracy, and reprocess unqualified products until they meet the standard.
6. Post-Processing Treatment: Clean the processed thread to remove metal chips and other debris on the thread surface; for threads that need anti-corrosion treatment, perform preliminary anti-rust treatment to protect the thread and extend its service life; mark the thread type and specifications for subsequent use and quality traceability.

To ensure the safety of the processing process, the precision of the thread, and the reliability of the subsequent pipe connection, the following precautions must be strictly observed during the threading process:
- Parameter Control: Strictly follow international standards and customer requirements to set threading parameters (thread type, dimension, pitch, thread angle, etc.), and avoid random adjustment of parameters, which may lead to unqualified thread and affect the connection effect.
- Equipment Operation: Operators must be trained and certified before taking up the job, and strictly operate the threading equipment in accordance with the operating procedures. It is forbidden to operate the equipment without authorization or modify the equipment parameters, and regular maintenance and inspection of the equipment are required to avoid equipment failure.
- Material Adaptation: For different materials of steel pipes, select the appropriate threading speed and tool. For high-hardness materials (such as alloy steel), appropriately reduce the processing speed to avoid tool wear and thread defects; for stainless steel, take anti-adhesion measures to avoid thread damage.
- Workpiece Protection: During processing, avoid scratching the thread surface and the pipe body. After processing, handle the workpiece gently to avoid collision and damage to the thread, which may affect the connection tightness.
- Safety Protection: Operators must wear personal protective equipment (gloves, goggles, protective clothing, etc.) during operation to avoid injury caused by metal chips splashing during threading.
- Quality Inspection: Conduct full-process quality inspection during threading. For each batch of workpieces, sampling inspection and full inspection are combined to ensure that the thread quality meets the requirements. Unqualified workpieces are not allowed to enter the next process.