MS17987 Quick Release Ball Lock Pin | Ring Handle | NAS1333-1343 Standard | JDF
The MS17987 Quick Release Ball Lock Pin is a ring-handle, single-acting ball lock pin manufactured to the MS17987 / NAS1333-1343 aerospace standard. The ring handle allows operation with a finger or connection to a lanyard, making it suitable for applications where a compact, low-profile handle is preferred. The pin is made from precipitation-hardened 17-4PH stainless steel (AMS5643) with 440C stainless steel balls, offering high shear strength and excellent corrosion resistance. The spring-loaded balls engage close-fitting holes to lock the pin securely in place, and will not release until the button on the handle is depressed. All pins are tested according to NAS 1332.
How to select the right MS17987 Ball Lock Pin:
Determine the nominal diameter: Match the pin diameter to the mounting hole. Recommended hole tolerance is H11. The MS17987 standard covers nominal diameters from 3/16" to 1".
Measure the clamping length: The clamping length is the distance from the bottom of the handle to the top of the locking ball. It must match the total thickness of the plates being joined. Standard clamping lengths range from 0.7" to 7.3".
Calculate the load: Determine the shear load the pin will experience. Apply a safety factor of 2 for static loading, or 3 for dynamic/impact loading. The required shear strength = actual load × safety factor. Refer to the double shear strength table above.
Confirm the standard part number: Each diameter/clamping length combination has a unique MS17987 part number (e.g., MS17987C539 for 5/16" diameter and 3.9" clamping length).
Example: For a 500 kg static load in double shear, with a safety factor of 2, the required shear strength is 1000 kg (approx. 2200 lbf). A 3/16" diameter pin (double shear strength 5,150 lbf) is more than sufficient.
Installation and Operation:
Insert the pin into the mounting hole with the button depressed. The spring-loaded balls retract, allowing the pin to slide through.
Release the button. The balls spring out and engage the groove or hole on the far side, locking the pin in place.
The ring handle allows operation with a single finger and can be connected to a lanyard to prevent loss.
To remove, press the button. The balls retract and the pin can be pulled out.
All CRES parts are passivated according to AMS2700 for corrosion resistance.
Technical Specifications Table
Nominal Dia. A (in) Clamping Length Range (in) Double Shear Strength (lbf/kN) Standard Part No. Example Body/Spindle Material 3/16" 0.7" - 4.5" 5,150 / 22.9 MS17987C307 17-4PH 1/4" 0.7" - 6.0" 9,200 / 40.9 MS17987C443 17-4PH 5/16" 0.7" - 6.0" 14,400 / 64.1 MS17987C539 17-4PH 3/8" 0.7" - 6.0" 20,700 / 92.1 MS17987C639 17-4PH 7/16" 0.7" - 6.0" 28,500 / 126.8 MS17987C740 17-4PH 1/2" 0.7" - 6.0" 36,900 / 164.2 MS17987C840 17-4PH 5/8" 0.7" - 6.0" 57,800 / 257.1 MS17987C1015 17-4PH 3/4" 0.7" - 6.0" 83,200 / 370.1 MS17987C1230 17-4PH 1" 0.7" - 7.3" 147,200 / 654.8 MS17987C1640 17-4PH
Typical Applications
The MS17987 Ring Handle Ball Lock Pin is widely used in the following applications:
Aerospace: Aircraft access panels, landing gear pins, and ground support equipment (GSE), conforming to MS17987 / NAS1333-1343 standards
Military Equipment: Quick locking and release for military vehicles, weapon systems, and field equipment
MRO Maintenance & Repair: Quick release of panels and covers in aircraft and engine maintenance
Fixtures & Positioning: Quick locating and locking of workpieces on precision fixtures, with ring handle suitable for lanyard connection
Marine & Offshore: Corrosion-resistant quick connections for marine equipment and offshore platforms
Industrial Equipment Maintenance: Quick fastening of frequently removed panels, covers, and guards
FAQ
Q1: What is the difference between MS17987 and MS17985?
A: MS17987 uses a ring handle, which is compact and suitable for finger operation or lanyard connection. MS17985 uses a T-handle, which extends perpendicular to the pin axis for maximum pulling leverage, suitable for heavy-duty equipment and gloved-hand operation. Both conform to NAS1333-1343 standards.
Q2: What material is MS17987 made of?
A: The body and spindle are made from CRES 17-4PH precipitation-hardened stainless steel (AMS5643). The balls are CRES 440C stainless steel (HRC 58-62). The spring is CRES 302 stainless steel. All CRES parts are passivated according to AMS2700.
Q3: What is the operating temperature range of MS17987?
A: The operating temperature range is -65°F to +200°F (-54°C to +93°C).
Q4: How do I determine the load capacity of MS17987?
A: MS17987 load capacity is measured by double shear strength. Values range from 5,150 lbf (3/16") to 147,200 lbf (1"). Apply a safety factor of 2 for static loads, or 3 for dynamic/impact loads.
Q5: How do I select the clamping length for MS17987?
A: The clamping length is the distance from the bottom of the handle to the top of the locking ball. It must match the total thickness of the plates being joined. MS17987 covers clamping lengths from 0.7" to 7.3".
