
Image shown is representative and may differ from the actual product in size, proportions, and color shade
3.500 in
(88.90 mm)
5.380 in
(136.65 mm)
1/2"

SIL SI55OR55 Ring Gasket, Size: 150#-3"-RN-1/2"
Material: SIL SI55OR55 Ring Gasket
Size: 150#-3"-RN-1/2" Ring Gasket
Part Number: SI55OR55-150#-3"-RN-1/2"
SI55OR55
Silicone (VMQ)
55
Shore A
Low Temperature Material
Low Compression Set
PVMQ Type Silicone
Color: Orange
Detailed Description
SI55OR55-150#-3"-RN-1/2" is a Orange, 55 Shore A, Silicone (VMQ) Ring Gasket, a PVMQ Type Silicone product. It is a 55 durometer Silicone (VMQ). [SI55OR55 is manufactured with the following features & specifications: Low Temperature Material, Low Compression Set. SI55OR55-150#-3"-RN-1/2" is size 150#-3"-RN-1/2" Ring Gasket also referred to as 3 (Pipe Size) x 88.9mm (ID) x 136.65mm (OD) x 1/2" (Thickness). SI55OR55-150#-3"-RN-1/2" is a size 3, 150#-RN ASME Ring Gasket. Material: 55 Durometer SIL SI55OR55 Ring Gasket Size: 150#-3"-RN-1/2", 3 Pipe Size X 88.9mm ID X 136.65mm OD X 1/2" Thickness

| Technical Specification | Value |
|---|---|
| Compound Number | SI55OR55 |
| Material | Silicone (VMQ) |
| Subtype | PVMQ Type Silicone |
| Color | Orange |
| Durometer | 55 Shore A Hardness |
| High Temperature | 205 °C / 401 °F |
| Low Temperature | -82 °C / -116 °F |
| Geometry Specifications | |
| Type | Ring Gasket |
| Size | 150#-3"-RN-1/2" |
| Pipe Size | 3 |
| ID | 88.90 mm / 3.500 in |
| OD | 136.65 mm / 5.380 in |
| Thickness | 1/2" |
SI55OR55 is a 55 shore A orange PVMQ silicone compound manufactured to A-A-59588 (1A-50) and (1B-50) specifications, designed for low temperature sealing applications requiring improved compression set resistance. This material provides excellent flexibility down to -82°C, making it ideal for O-rings and gaskets used in aerospace, automotive, and industrial systems exposed to extreme cold. It also offers strong resistance to thermal degradation, along with durability against oxygen, ozone, UV exposure, and fungal growth for long-term reliability. SI55OR55 meets ASTM D2000 4GE507 requirements and delivers consistent performance in demanding low temperature environments.
PVMQ, or fluorosilicone rubber, is a specialized elastomer that combines the low temperature flexibility of silicone with improved resistance to fuels, oils, and certain solvents. These materials are widely used in O-rings and gaskets where both chemical exposure and extreme temperature conditions are present. Compared to standard silicone, PVMQ offers better fuel compatibility while maintaining excellent cold temperature performance, making it a preferred choice for aerospace and automotive sealing applications. While highly versatile, it may not match FKM in high temperature chemical resistance, so proper material selection is essential.
Keywords: SI55OR55, SI 55OR55, SI-55OR55, SI55 OR55, PVMQ silicone rubber, low temp fluorosilicone, A-A-59588 1A-50 1B-50, 55A elastomer, extreme cold O-rings, fuel resistant silicone gasket, ASTM D2000 4GE507, aerospace sealing material, compression set resistant rubber, Datasheet, TDS, Test Report, MTR, MSDS, SDS


