Product Specifications
| Model / Specification | M10 - M36 |
| Material | Carbon Steel |
| Nom. Dia. d |
M10 | M10 | M12 | M12 | (M14) | M16 | (M18) | M20 | (M22) | M24 | (M24) | M30 | (M30) | M36 | |
| P | Pitch | 1.25 | 1.5 | 1.25 | 1.75 | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 2 | 1.5 | 2 | 1.5 |
| L | Nom. | 8 | 8 | 8 | 8 | 14 | 14 | 14 | 14 | 14 | 14 | 14 | 12 | 12 | 12 |
| Max. | 8.3 | 8.3 | 8.3 | 8.3 | 14.3 | 14.3 | 14.3 | 14.3 | 14.3 | 14.3 | 14.3 | 12.3 | 12.3 | 12.3 | |
| Min. | 7.7 | 7.7 | 7.7 | 7.7 | 13.7 | 13.7 | 13.7 | 13.7 | 13.7 | 13.7 | 13.7 | 11.7 | 11.7 | 11.7 | |
| k | Nom. | 3 | 3 | 3 | 3 | 3 | 3 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
| Max. | 3.2 | 3.2 | 3.2 | 3.2 | 3.2 | 3.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | 4.2 | |
| Min. | 2.8 | 2.8 | 2.8 | 2.8 | 2.8 | 2.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | |
| s | Nom. | 5 | 5 | 6 | 6 | 6 | 8 | 8 | 10 | 10 | 12 | 12 | 14 | 14 | 17 |
| Max. | 5.095 | 5.095 | 6.095 | 6.095 | 6.095 | 8.115 | 8.115 | 10.115 | 10.115 | 12.142 | 12.142 | 14.142 | 14.142 | 17.2 | |
| Min. | 5.02 | 5.02 | 6.02 | 6.02 | 6.02 | 8.025 | 8.025 | 10.025 | 10.025 | 12.032 | 12.032 | 14.032 | 14.032 | 17.05 | |
| e | Min. | 5.72 | 5.72 | 6.86 | 6.86 | 6.86 | 9.15 | 9.15 | 11.43 | 11.43 | 13.72 | 13.72 | 16 | 16 | 1.944 |
| dk | Max. | 16 | 16 | 18 | 18 | 20 | 22 | 24 | 26 | 28 | 32 | 32 | 38 | 38 | 44 |
| Min. | 15 | 15 | 17 | 17 | 19 | 21 | 23 | 25 | 27 | 31 | 31 | 37 | 37 | 43 | |
| t | Min. | 4 | 4 | 5 | 5 | 5 | 5 | 5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 |
| z | ≈ | 1.3 | 1.5 | 1.3 | 1.3 | 1.8 | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 2 | 1.5 | 2 | 1.5 |
Automobile Parts — Type 2C Flat Round Head Hexagon Socket Straight Pipe Plug — Product Introduction
The Type 2C flat round head hexagon socket straight pipe plug is a sealing plug used for process holes or inspection holes in assemblies such as automobile engines, transmissions, brake systems and hydraulic systems. Its head is a flat round shape with a hexagon socket on the top, allowing operation with a hex key. The threaded portion uses a straight pipe thread (cylindrical pipe thread, such as G/BSPP or metric fine straight thread), which requires the use of a sealing washer, O-ring or sealant to achieve face sealing. The product complies with relevant automotive industry standards. Common materials include carbon steel (such as Y15, SUM24L, SWRCH10R) or stainless steel. Surface treatments are mostly zinc plating, blackening, phosphating or passivation to meet corrosion resistance and assembly requirements.
1. Product Features
• Flat round head with hexagon socket: The head has a low flat arc shape, with small exposed height after installation and a neat appearance. The hexagon socket allows easy installation and removal with a standard hex key.
• Straight pipe thread design: The thread is a cylindrical pipe thread with a fixed pitch. The thread itself does not provide sealing taper, so face sealing must be achieved by using sealing elements such as bonded washers or O-rings.
• Small space occupation: The low-profile head is suitable for installation in confined spaces or counterbored holes without affecting the layout of surrounding components.
• Various materials available: Carbon steel, stainless steel and other materials are commonly used and can be selected according to the medium, temperature and corrosive environment.
• Complete surface treatment: Zinc plating, blackening, phosphating, passivation and other treatments can be applied to improve corrosion resistance and assembly appearance.
• Good interchangeability: The thread dimensions conform to relevant pipe thread standards and fit standard straight pipe threaded holes, providing strong versatility and easy maintenance and replacement.
2. Product Advantages
• Reliable face sealing: Stable face sealing can be achieved when used with a bonded washer or O-ring, making it suitable for medium and low pressure hydraulic, pneumatic and lubricating oil circuits.
• Easy installation and removal without thread damage: The hexagon socket drive provides even force and is not prone to rounding. The straight pipe thread has no taper locking, so removal causes less wear to the base thread and allows repeated assembly and disassembly.
• Neat and attractive appearance: The flat round head design keeps the plug almost flush with the housing surface after installation, with no protruding sharp parts, improving the overall appearance of the assembly.
• Accurate positioning and stable torque: The screw-in depth of the straight pipe thread can be controlled. When used with a torque wrench, the preload can be precisely controlled to avoid over-tightening or under-tightening.
• Good vibration resistance: When fitted with an elastic sealing washer, it can effectively absorb vibration and maintain the sealing condition, making it suitable for automotive vibration working conditions.
• Cost-effective: Simple structure and easy processing with ordinary materials make it suitable for mass production and wide application.
3. Application Scope
The Type 2C flat round head hexagon socket straight pipe plug is mainly used for process holes, inspection holes, drain holes, exhaust holes and other positions requiring face sealing in various automotive assemblies. Common applications include:
• Engine: Process holes in cylinder block and cylinder head oil passages and water passages, oil filter housing holes, etc.
• Transmission: Sealing of housing oil passages, oil filler holes, drain holes and inspection holes.
• Brake system: Plugging of fluid holes and air holes on brake valve bodies and brake caliper bodies.
• Steering system: Sealing of holes on steering gear housings and power steering pump bodies.
• Hydraulic system: Holes requiring straight pipe threads with face sealing, such as hydraulic valve blocks, pump bodies and motors.
• Fuel system: Plugging of process holes on fuel pumps and filter housings.
• Other industries and construction machinery: Various holes requiring cylindrical pipe threads used together with sealing washers.
