How to Measure Metric Grease Fitting Sizes Accurately

How to Measure Metric Grease Fitting Sizes Accurately

How to Measure Metric Grease Fitting Sizes Accurately

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Metric grease fittings, also known as Zerk fittings, allow for the effective lubrication of machinery components, ensuring smooth operation and longevity. These small but vital components come in different sizes, and using the correct size is essential to prevent equipment failure, reduce downtime, and maintain safety standards. This comprehensive guide aims to provide clear, step-by-step instructions on how to measure metric grease fitting sizes accurately, ensuring that maintenance professionals and engineers can select the right fittings for their specific applications.

Understanding Metric Grease Fittings

Metric grease fittings are small components designed to facilitate the lubrication of mechanical systems. These fittings allow for the introduction of lubricant under pressure into bearing assemblies, pivot points, and other moving parts to reduce friction and wear. Unlike their imperial counterparts, metric grease fittings adhere to the metric system of measurements, making them essential for equipment and machinery designed with this standard.

There are several types of metric grease fittings, each suited for specific applications:

Straight Fittings: These are the most common type, featuring a straight-through passage for grease flow.

Angled Fittings: Available in 45-degree and 90-degree angles, these fittings are used where straight fittings cannot be installed due to space constraints.

Flush-Type Fittings: Designed to sit flush with the surface, these fittings are used in applications where protruding fittings could be damaged or interfere with operation.

Drive-Type Fittings: These fittings are installed by driving them into place and are used where threading is not feasible.

Button Head Fittings: These are larger fittings used in heavy machinery where higher volumes of grease are required.

Materials and Uses

Metric grease fittings are manufactured from various materials, each chosen for its specific properties and suitability for different environments:

Steel: The most common material used, steel fittings are durable and cost-effective, suitable for general-purpose applications.

Stainless Steel: Offering superior corrosion resistance, stainless steel fittings are ideal for harsh environments, including marine and chemical processing industries.

Brass: Known for its anti-corrosive properties, brass fittings are often used in applications involving water or mild chemicals.

Zinc-Plated Steel: These fittings provide an additional layer of corrosion resistance and are used in outdoor or moist environments.

Importance of Proper Sizing

Accurate sizing of metric grease fittings is paramount for several reasons:

Effective Lubrication: Properly sized fittings ensure that lubricant reaches all necessary parts of the machinery, reducing friction and wear.

Preventing Leaks: Incorrectly sized fittings can lead to leaks, resulting in insufficient lubrication and potential equipment failure.

Ease of Maintenance: Correctly sized fittings simplify the maintenance process, allowing for quick and efficient lubrication without the need for adapters or modifications.

Safety: Ensuring the right size fittings helps maintain the safety of the equipment, preventing malfunctions that could lead to accidents.

Step-by-Step Measurement Process

Accurately measuring metric grease fittings requires careful preparation and the right tools. This section will guide you through each step of the process to ensure precise measurements.



Cleaning the Fitting: Before measuring, thoroughly clean the grease fitting to remove any dirt, grease, or debris. Use a solvent or degreaser and a brush to ensure all residues are removed, as contaminants can affect measurement accuracy.

Inspection: Inspect the fitting for any visible damage or wear. Bent or damaged fittings should not be used for measurement as they can provide inaccurate readings. Replace any defective fittings before proceeding.

Drying: Ensure the fitting is completely dry after cleaning. Moisture can also interfere with accurate measurements.

Measuring the Diameter

External Diameter

Select the Right Tool: Use a pair of digital or vernier calipers for precise measurement.

Position the Calipers: Open the calipers and place them around the external diameter of the fitting’s threaded part. Ensure the jaws of the calipers are perpendicular to the axis of the fitting to avoid skewed measurements.

Take the Measurement: Gently close the caliper jaws until they touch the fitting’s surface without applying excessive force. Read the measurement displayed on the calipers.

Record the Measurement: Note down the external diameter to the nearest hundredth of a millimeter for accuracy.

Internal Diameter

Select the Tool: For internal diameters, you can use either a pair of small calipers or a micrometer.

Insert the Calipers: Carefully insert the caliper jaws into the internal bore of the fitting. For micrometers, place the spindle inside the bore.

Take the Measurement: Open the calipers or extend the micrometer spindle until they touch the internal walls of the fitting. Ensure the tool is aligned properly to avoid angled measurements.

Record the Measurement: Read and record the internal diameter.

Measure Metric Grease Fitting

Measuring the Thread Pitch

Thread pitch is the distance between threads, measured in millimeters. It is crucial for ensuring compatibility with corresponding components. Accurate thread pitch measurement ensures that the fitting will mate correctly with the receiving part, preventing leaks and mechanical failures.

Using a Thread Gauge

Select the Thread Gauge: Choose a metric thread gauge that includes various pitch sizes.

Match the Threads: Align the teeth of the thread gauge with the threads of the fitting. Start with a pitch size that seems close to the fitting’s thread.

Check the Fit: If the gauge does not fit perfectly, try the next size until you find a match where the gauge teeth align seamlessly with the fitting’s threads.

Record the Pitch: Once you find the correct thread pitch, record the measurement indicated on the gauge.

Measuring the Length

Overall Length

Select the Right Tool: Use a ruler or a set of calipers.

Position the Tool: Align the ruler or calipers with the fitting’s axis to measure from end to end.

Take the Measurement: Measure the entire length of the fitting, including both the threaded and non-threaded parts.

Record the Measurement: Note down the overall length.

Threaded Length

Identify the Threaded Part: Locate the beginning and end of the threaded section of the fitting.

Position the Tool: Place the ruler or calipers at the start of the threads and extend them to the end of the threads.

Take the Measurement: Measure the length of the threaded part.

Record the Measurement: Note the threaded length separately from the overall length.

Common Mistakes and How to Avoid Them

Accurate measurement of metric grease fittings is crucial for ensuring the proper function and longevity of mechanical systems. However, several common mistakes can lead to incorrect measurements, which can cause equipment malfunctions and increased maintenance costs. Understanding these mistakes and how to avoid them is essential for any maintenance professional or engineer.

Incorrect Tool Usage

Common Mistakes:

Using the Wrong Tool: Using a ruler instead of calipers for diameter measurements, or not using a thread gauge for thread pitch, can lead to inaccurate readings.

Improper Calibration: Not calibrating measurement tools before use can result in significant errors.

Inappropriate Pressure: Applying too much or too little pressure with calipers can skew the measurements.

Incorrect Positioning: Misaligning calipers or micrometers can lead to inaccurate diameter and length measurements.

How to Avoid Them:

Choose the Right Tool: Ensure you are using the appropriate tool for each measurement. Use calipers for diameters, micrometers for small internal diameters, and thread gauges for thread pitch.

Calibrate Tools: Regularly calibrate your measurement tools according to the manufacturer’s instructions to ensure accuracy.

Apply Gentle Pressure: When using calipers, apply gentle and consistent pressure to avoid compressing or distorting the fitting.

Align Properly: Ensure that calipers and micrometers are perpendicular to the surface being measured. This alignment helps avoid angular discrepancies.

rust Metric Grease Fitting

Misreading Measurements

Common Mistakes:

Misinterpreting the Scale: Misreading the scale on a vernier caliper or micrometer can lead to incorrect measurements.

Recording Errors: Failing to record measurements immediately or incorrectly noting them down can cause confusion and errors.

Ignoring Decimal Points: Overlooking decimal points in digital readings can result in significant inaccuracies.

Tips on Accurate Reading and Recording:

Understand the Scale: Familiarize yourself with the scales on your measurement tools. For vernier calipers, understand how to read both the main scale and the vernier scale.

Double-Check Readings: Always double-check your readings before recording them. Cross-reference with a colleague if possible.

Use Digital Tools: If available, use digital calipers and micrometers for easier and more accurate readings.

Record Immediately: Write down measurements as soon as they are taken to avoid memory lapses or errors.

Check Decimal Points: Pay close attention to decimal points and ensure they are accurately recorded.

Ignoring Tolerances

Common Mistakes:

Neglecting Manufacturer Specifications: Ignoring the tolerances specified by the manufacturer can lead to poor fitting and mechanical failures.

Assuming Exact Fit: Believing that all fittings are manufactured to exact sizes without considering allowable variances can cause issues.

Importance of Considering Manufacturing Tolerances:

Fit and Function: Manufacturing tolerances account for slight variances in the production process. Understanding these tolerances ensures that parts will fit and function correctly even if there are minor differences in size.

Avoiding Over-tightening: Recognizing that fittings may vary within a specified range helps prevent over-tightening, which can damage parts and lead to leaks.

How to Account for Tolerances:

Refer to Specifications: Always refer to the manufacturer’s specifications for tolerances. These specifications provide an acceptable range of dimensions for each fitting.

Measure Multiple Times: Take multiple measurements to ensure consistency and accuracy. Variations in your readings can help you understand the tolerance range.

Adjust Measurements: If your measurements are close to the tolerance limits, consider the intended application and whether slight adjustments might be needed.

How to Choose the Suitable Metric Grease Fittings

Selecting the appropriate metric grease fittings is crucial for ensuring efficient lubrication and the smooth operation of mechanical systems. The right choice can prevent equipment failure, reduce maintenance costs, and extend the lifespan of machinery. Here’s a comprehensive guide on how to choose the suitable metric grease fittings.

Understand Your Application

Identify the Equipment Type:

Determine the type of machinery or equipment that requires lubrication. Different machines have different lubrication needs and constraints.

Operating Conditions:

Consider the operating environment, including temperature, humidity, and exposure to chemicals or corrosive substances. This will influence the material choice for the grease fittings.

Lubrication Requirements:

Understand the type and viscosity of the lubricant to be used, as this can affect the choice of fitting.

Consider the Size and Thread Type

Measure Existing Fittings:

If replacing existing fittings, measure the old ones to ensure a proper fit. Use calipers and thread gauges for accurate measurements.

Standard Sizes:

Refer to standard metric sizes to ensure compatibility with existing components. Cross-reference your measurements with industry standards.

Thread Type:

Ensure the thread type matches the receiving component. Common thread types include metric fine and coarse threads.

Evaluate Installation and Maintenance Requirements

Ease of Installation:

Choose fittings that are easy to install and do not require special tools or equipment.

Maintenance Accessibility:

Consider how easy it will be to access the fittings for regular maintenance. Angled fittings may be necessary for hard-to-reach areas.

Factor in Load and Pressure Conditions

Load Bearing Capacity:

Ensure the fittings can handle the load and pressure of the equipment. Heavy machinery may require sturdier fittings like button head fittings.

Pressure Rating:

Verify that the fittings can withstand the pressure of the lubrication system. Consult manufacturer specifications for pressure ratings.

Consult Manufacturer Specifications and Recommendations

Manufacturer Guidelines:

Always refer to the machinery or equipment manufacturer’s guidelines for recommended grease fitting types and specifications.

Industry Standards:

Follow industry standards and best practices for selecting grease fittings to ensure safety and compatibility.

Choosing the right metric grease fittings involves understanding your specific application requirements, selecting the appropriate type and material, ensuring the correct size and thread type, considering installation and maintenance needs, and consulting manufacturer guidelines. By following these steps, you can ensure optimal performance, efficiency, and longevity of your mechanical systems.


In conclusion, accurately measuring metric grease fittings is essential for ensuring proper lubrication and the efficient operation of machinery. We covered the types of metric grease fittings, including straight, angled, flush-type, and button head fittings, and the appropriate materials for different applications, such as steel, stainless steel, brass, and zinc-plated steel. Accurate measurements involve using the right tools, avoiding common mistakes, and considering manufacturing tolerances. Precise measurements prevent equipment failures, reduce maintenance costs, and extend machinery lifespan. We encourage you to apply these measurement techniques in your work and share your experiences to help others achieve optimal performance and reliability in their operations.


Metric grease fittings, also known as Zerk fittings, are components used to lubricate mechanical systems by allowing grease to be injected into bearing assemblies and other moving parts.

Accurate measurement ensures proper lubrication, prevents leaks, reduces equipment failures, and extends the lifespan of machinery by ensuring the correct fitting size is used.

Common tools include calipers for measuring diameters, thread gauges for measuring thread pitch, and micrometers for precise internal diameter measurements.

Select the material based on the operating environment: steel for general use, stainless steel for corrosive environments, brass for applications involving water or mild chemicals, and zinc-plated steel for additional corrosion resistance.

The common types include straight fittings for direct access points, angled fittings for space-constrained areas, flush-type fittings for surfaces where protruding fittings could be damaged, and button head fittings for high-volume grease requirements in heavy machinery.

Double-check your measurements for accuracy and compare them with industry standards. If discrepancies persist, re-measure and consider manufacturing tolerances or consult with the fitting manufacturer for guidance.

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SAE Thread Fitting Types What You Need to Know

SAE vs Metric Grease Fittings: A Detailed Guide

SAE vs Metric Grease Fittings: A Detailed Guide


Grease fittings are small components that play an important role in machinery maintenance by allowing easy and efficient application of lubricant to moving parts. Proper lubrication is critical to minimizing wear, preventing corrosion, and extending equipment life. This detailed guide is designed to give readers a comprehensive understanding of SAE and metric grease fittings, including their features, applications, compatibility and selection criteria, so they can make informed decisions about their maintenance practices.

Understanding Grease Fittings

Grease fittings, also known as grease nipples or zerks, are mechanical components designed to facilitate the application of lubricants to moving parts of machinery. These fittings serve as access points through which grease can be injected directly into bearings, joints, and other components, ensuring that they remain well-lubricated and function smoothly. The primary function of grease fittings is to provide a sealed and secure pathway for lubricant delivery, preventing contaminants from entering the system and ensuring that lubrication reaches the intended areas effectively.

There are several types of grease fittings, each suited to different applications and environments. The most common types include:

Standard Grease Fittings: These are the most widely used and come in various thread sizes to fit different machinery. They feature a ball check mechanism that prevents dirt and debris from entering the fitting.

Flush Grease Fittings: These are designed to be flush with the surface of the machinery, making them less prone to damage in environments where protruding fittings might be knocked off or damaged.

Button Head Grease Fittings: Characterized by their larger diameter heads, these fittings are used in heavy-duty applications where a large volume of grease is required. They are particularly useful in industrial and construction equipment.

Proper lubrication is paramount in machinery maintenance, as it significantly reduces friction and wear between moving parts. Without adequate lubrication, components can quickly degrade, leading to increased downtime, higher maintenance costs, and a shorter lifespan for the machinery. Grease fittings ensure that the lubricant is delivered precisely where it is needed, enhancing the performance and reliability of the equipment. Additionally, regular lubrication through grease fittings helps in preventing rust and corrosion, which can compromise the integrity of the machinery over time.

Overview of SAE Grease Fittings

SAE grease fittings are predominantly used in the automotive industry, given their origins. However, their use has expanded to various other sectors, including agriculture, construction, aerospace, and heavy machinery. These fittings are integral to the maintenance of equipment such as tractors, excavators, aircraft, and industrial machines. The standardized nature of SAE fittings makes them highly versatile, suitable for a wide range of applications where reliable lubrication is critical.

Characteristics and Specifications of SAE Grease Fittings

SAE grease fittings are known for their precise engineering and durability. Key characteristics and specifications include:

Thread Sizes: SAE grease fittings come in a variety of thread sizes to accommodate different equipment requirements. Common thread sizes include 1/4″-28, 1/8″-27, 5/16″-18, and 3/8″-24, among others. These sizes correspond to specific applications and ensure a secure fit within the designated lubrication points.

Pressure Ratings: SAE grease fittings are designed to withstand varying pressure levels, ensuring that they can handle the demands of different lubrication systems. Typical pressure ratings for these fittings range from 6,000 to 10,000 psi, depending on the specific type and application. This ensures that the fittings can deliver lubricant effectively without leaking or failing under high pressure.

Materials Used: SAE grease fittings are typically made from durable materials such as steel, stainless steel, and brass. Steel fittings are commonly used due to their strength and cost-effectiveness. Stainless steel fittings offer superior corrosion resistance, making them suitable for harsh environments.

Overview of Metric Grease Fittings

Metric grease fittings are widely used in industries and regions that have adopted the metric system, including Europe, Asia, and many parts of Africa and Latin America. Common applications include automotive manufacturing, heavy machinery, industrial equipment, and agricultural machinery. Metric fittings are essential in maintaining equipment such as cars, trucks, construction vehicles, and farm equipment. Their use in these industries ensures that machinery remains well-lubricated and operates efficiently, reducing downtime and maintenance costs.

Characteristics and Specifications of Metric Grease Fittings

Metric grease fittings are designed to meet specific engineering standards, ensuring they provide reliable and efficient lubrication. Key characteristics and specifications include:

Thread Sizes: Metric grease fittings come in a range of thread sizes to suit different machinery and applications. Common thread sizes include M6x1, M8x1, M10x1, and M12x1. These sizes denote the diameter and pitch of the threads, allowing for precise fitting and secure attachment within lubrication points.

Pressure Ratings: Metric grease fittings are built to withstand high-pressure environments, ensuring they can deliver lubricant effectively without leakage or failure. Typical pressure ratings for these fittings range from 6,000 to 10,000 psi, similar to SAE fittings. This ensures they can handle the demands of various lubrication systems and maintain consistent performance under pressure.

Materials Used: The materials used in the construction of metric grease fittings are chosen for their durability and resistance to wear and corrosion. Common materials include steel, stainless steel, and brass. Steel fittings are favored for their strength and affordability, making them suitable for general applications. Stainless steel fittings offer excellent corrosion resistance and are ideal for use in harsh or corrosive environments. Brass fittings are also used for their corrosion resistance and ease of machining, often found in specialized applications where precision is critical.

Key Differences Between SAE and Metric Grease Fittings

Measure Metric Grease Fitting drawing

Thread Types and Sizes Comparison

One of the most notable differences between SAE and Metric grease fittings lies in their thread types and sizes. SAE (Society of Automotive Engineers) grease fittings typically use imperial thread sizes, such as 1/4″-28, 1/8″-27, 5/16″-18, and 3/8″-24. These threads are specified in inches and follow the Unified Thread Standard (UTS).

On the other hand, Metric grease fittings use thread sizes measured in millimeters, such as M6x1, M8x1, M10x1, and M12x1. The “M” denotes that the threads are metric, and the numbers indicate the diameter and pitch of the threads. The pitch refers to the distance between threads, which is crucial for ensuring a proper fit.

This difference in thread types means that SAE and Metric grease fittings are not directly interchangeable. Using the wrong type of thread can result in poor fitment, potential leakage, and damage to the machinery.

Dimensional Differences and Tolerances

SAE and Metric grease fittings also differ in their dimensional standards and tolerances. SAE fittings follow the UTS dimensional standards, which have specific guidelines for thread depth, diameter, and pitch. These standards ensure consistency and compatibility among various SAE fittings.

Metric grease fittings adhere to the International Organization for Standardization (ISO) standards, which dictate the dimensions and tolerances for metric threads. ISO standards ensure that Metric fittings maintain consistent thread dimensions and pitches, facilitating their use in metric-based systems.

Dimensional differences and tolerances between SAE and Metric fittings can affect the ease of installation and the reliability of the seal. Properly adhering to these standards is essential to ensure that the fittings perform optimally and do not cause mechanical issues.

Pressure Ratings and Performance Differences

While both SAE and Metric grease fittings are designed to handle high pressures, there can be differences in their performance based on their construction and application. Typical pressure ratings for both types of fittings range from 6,000 to 10,000 psi. However, specific applications might require fittings that can handle higher or lower pressures.

SAE fittings are often used in applications with rigorous performance requirements, such as automotive and aerospace industries. Their pressure ratings and performance are standardized to meet the stringent demands of these sectors.

Metric fittings, while also capable of handling high pressures, are commonly used in industrial and machinery applications. Their performance standards are set to meet the needs of these environments, ensuring reliable lubrication under various conditions.

Selection Criteria

Choosing the right grease fittings for your machinery is crucial for ensuring efficient lubrication and long-term reliability. When selecting between SAE and Metric grease fittings, several factors should be considered to ensure compatibility, performance, and ease of maintenance.

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Performance Requirements

Load and Pressure: Assess the operational load and pressure requirements of your machinery. High-load and high-pressure applications may require fittings with specific pressure ratings. Ensure that the selected grease fittings can handle the maximum pressure without risk of leakage or failure.

Lubricant Delivery: Consider the type and viscosity of the lubricant used. Some fittings are designed to accommodate thicker greases, while others are optimized for lighter oils. The fitting should ensure consistent and effective lubricant delivery to the critical parts of the machinery.

Frequency of Lubrication: Determine how often the machinery requires lubrication. Frequent lubrication needs might necessitate fittings that are easy to access and use, while less frequent needs might allow for more secure, less accessible fittings.

Environmental Factors

Operating Environment: Evaluate the conditions in which the machinery operates. In harsh environments with exposure to dirt, dust, moisture, or chemicals, corrosion-resistant materials like stainless steel or brass may be necessary to ensure longevity and reliability.

Temperature Extremes: Consider the temperature range within which the machinery operates. Extreme temperatures can affect the performance and durability of grease fittings. Materials and designs that can withstand high or low temperatures without degradation are preferable.

Exposure to Contaminants: Machinery exposed to contaminants requires grease fittings with effective sealing mechanisms to prevent dirt and debris from entering the lubrication system. This ensures the lubricant remains clean and effective.

Maintenance Considerations

Ease of Installation and Removal: Choose grease fittings that are easy to install and remove. This is particularly important for machinery that requires frequent maintenance. Quick and straightforward installation helps reduce downtime and maintenance costs.

Compatibility with Existing Equipment: Ensure that the new grease fittings are compatible with the existing equipment. This includes matching thread sizes, types, and material compatibility. Using fittings that align with current standards and specifications prevents potential issues during maintenance.

Availability and Replacement: Consider the availability of the grease fittings in your region. Easily accessible fittings reduce downtime when replacements are needed. Standardized fittings (either SAE or Metric) that are widely available can be advantageous.

Durability and Longevity: Select fittings made from high-quality materials that offer durability and long service life. This minimizes the need for frequent replacements and ensures continuous, reliable lubrication.

Selecting the right grease fittings involves a comprehensive evaluation of performance requirements, environmental factors, and maintenance considerations. By understanding the specific needs of your machinery and the conditions it operates in, you can choose grease fittings that enhance lubrication efficiency, reduce maintenance efforts, and extend the lifespan of your equipment. Whether opting for SAE or Metric fittings, ensuring compatibility and reliability is key to achieving optimal machinery performance and operational efficiency.

Installation and Maintenance Tips

Preparation: Before installation, ensure that the fitting and the receiving hole are clean and free from debris or old grease. Use a clean cloth or brush to remove any contaminants.

Thread Sealing: Apply a suitable thread sealant or Teflon tape to the threads of the grease fitting to prevent leaks and ensure a secure fit. This is especially important in high-pressure applications.

Insertion: Carefully screw the grease fitting into the receiving hole by hand to avoid cross-threading. Once it is hand-tight, use a wrench or a special grease fitting installation tool to secure it firmly in place. Avoid over-tightening, which can damage the threads and the fitting.

Alignment: Ensure the grease fitting is aligned correctly to allow easy access for the grease gun. Misalignment can make future lubrication difficult and may cause damage during maintenance.

Common Installation Mistakes and How to Avoid Them

Cross-Threading: One of the most common mistakes is cross-threading the fitting during installation. To avoid this, always start threading the fitting by hand and ensure it is properly aligned before using a wrench.

Over-Tightening: Over-tightening can strip the threads or damage the fitting. Tighten the fitting until it is snug and then apply a slight additional turn for security. Do not force it beyond this point.

Inadequate Sealing: Failing to use a thread sealant can lead to leaks. Always apply a suitable sealant to the threads before installation.

Troubleshooting Common Problems

Grease Leakage: If grease is leaking around the fitting, check for proper installation and ensure that the threads are sealed correctly. Replace damaged or worn fittings.

Blocked Fittings: If no grease is coming out when you apply the grease gun, the fitting may be blocked. Remove the fitting and clean it or replace it if necessary. Check the passage in the machinery for blockages as well.

Fitting Damage: If the fitting is damaged, bent, or worn, replace it immediately. Operating with a damaged fitting can lead to insufficient lubrication and potential machinery failure.

Difficulty in Lubrication: If it is hard to attach the grease gun or apply grease, ensure that the fitting is the correct type and size for your equipment. Also, check that the grease gun is functioning properly and filled with the correct lubricant.


In this detailed guide, we have explored the differences between SAE and metric grease fittings. By thoroughly evaluating these needs and understanding the unique benefits of each standard, you can make an informed decision that ensures optimal lubrication, performance, and service life for your equipment.


SAE grease fittings use imperial thread sizes and are commonly used in the US, while Metric grease fittings use metric thread sizes and are prevalent in Europe and Asia.

No, SAE and Metric grease fittings are not interchangeable due to differences in thread types and sizes.

Common materials for grease fittings include steel, stainless steel, and brass, chosen for their durability and corrosion resistance.

To prevent cross-threading, always start threading the fitting by hand, ensuring it is properly aligned before using a wrench to secure it.

Thread sealant prevents leaks and ensures a secure fit, especially important in high-pressure applications.

Regularly inspect grease fittings for wear, damage, and blockages. Follow the manufacturer’s recommended lubrication schedule and keep fittings clean to ensure optimal performance.

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The hydraulic grease fitting is a small liquid check valve, usually with a ball valve inside, that controls the flow of grease in and out, preventing fluid leakage and the entry of dust. The types of grease fittings include button head grease fittings, push-in grease fittings, pressure relief grease fittings, thread forming grease fittings, etc. And are used in a wide range of applications.

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Hydraulic grease fittings can also be called Zerks, which are special hydraulic check valve fittings that can be used to connect bearings and some mechanical internal parts. Grease nipple fittings are also available in a wide variety of threads, including SAE, BSP, NPT, UNF, Metric, etc, and can be used in many applications. The features of grease fittings are as follows:

  1. Perfect leak-proof capability
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Hydraulic grease fittings are used in a wide range of applications, whether in agriculture, industry, automotive, or some other field. Hydraulic grease fittings provide perfect leak-free capability and anti-pollution properties.

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The construction industry is one of the most important contributors to economic development, where hydraulic grease fittings provide many benefits to the development of the industry, it can increase the efficiency and productivity of machines.

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Topa supplies high quality hydraulic grease fitting for agriculture market. Grease fittings, also known as Zerks, are a type of hydraulic check valve that can be used for bearings and some internal mechanical parts to provide lubrication.

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Topa's hydraulic grease fitting can be used in mining field. Because of its special advantages, the grease fitting can be used in various applications with lubrication and dust protection needs in automotive, industrial, agricultural, aerospace, mining and other fields.

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For each Topa product, multiple checks such as manufacturing monitoring, quality testing and packaging inspection are carried out to ensure the quality and level of the product.


What are grease hydraulic fittings?

Grease fittings, also known as Zerks, are a type of hydraulic check valve that can be used for bearings and some internal mechanical parts to provide lubrication.

What are the types of hydraulic grease fitting?

The most commonly used types of hydraulic grease fittings are as follows: push button head grease fittings, push-in grease fittings, pressure relief grease fittings, thread forming grease fittings, and ball type fittings, etc.

What are the uses of hydraulic grease fitting?

Because of its special advantages, the grease fitting can be used in various applications with lubrication and dust protection needs in automotive, industrial, agricultural, aerospace, mining and other fields.

What are the advantages of hydraulic grease fitting?

Grease fitting is also very advantageous because of its special construction. It can stop dust and some other contamination from entering the parts, it can prevent leaks, and it can also provide lubrication.

How many threads of grease fittings?

The most commonly used threads for hydraulic grease fittings are SAE-LT and NPT threads, besides, BSP, BSPT, UNF, metric threads can also be used on grease fittings.

What are the materials of grease fittings?

Hydraulic grease fittings are made of a diverse array of materials, including brass, galvanized steel, stainless steel and more.

How to identify grease fitting thread?

The type of thread is determined by first looking carefully at whether the thread is straight or angled, then measuring the pitch, and finally measuring the diameter of the thread.

How does grease fitting work?

There is a ball check valve inside the hydraulic grease fitting. After the grease enters the fitting, it will generate pressure on the check valve and the ball valve will open to let the grease enter smoothly. After the grease enters, the pressure disappears and the check valve returns to the closed state to prevent fluid flow or contamination from entering.

Can you over grease a grease fitting?

It is best not to use excessive grease. Too much grease can cause temperature imbalance and energy loss in the parts, and it can also damage some of the parts.

How to protect grease fittings?

When using grease fittings, pick standard fittings, use high quality grease, and remember to clean the fittings to prevent dust and other contamination from being pushed into the bearings. If the fittings are damaged, be sure to replace them in time.

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