SST-QST

Supported Applications

The Omega SST & QST Split Sheath Insertion Heaters are designed for platen, die, or mold heating applications where holes in process equipment are poorly drilled or worn through age. These ruggedly constructed heaters feature a split sheath design intended to accommodate such conditions while providing long life and dependable service when properly installed.

Operating Conditions & Performance

The series utilizes an Incoloy® sheath material, with maximum recommended temperatures on the sheath reaching 1600°F (871°C). For configurations using flexible leads, the ambient temperature at the leadwire end must not exceed 850°F (450°C) to remain within the rating of the lead insulation and end seal material. The heaters are available in nominal sheath diameters ranging from 3/8" to 1", with actual diameters specified as .370", .495", .620", .682", .745", and .995" (±.003). Insertion lengths range from a minimum of 5" up to 60" for SST models, while QST models support insertion lengths up to 36".

Electrical performance tolerances are defined by the series specifications: wattage tolerance is +5% – 10%, and resistance tolerance is +10% – 5%. Sheath length tolerances are ±3% for lengths up to 20" and ±2% for lengths over 20". The heaters support standard voltages including 120 Vac, 240 Vac, 380 Vac, and 480 Vac.

Configuration Options

The SST & QST series offers configurable dimensions across the full documented envelope:

• Diameter Options: Nominal sizes of 3/8", 1/2", 5/8", 11/16", 3/4", and 1". Note that QST (Quad) configurations are not available in the 3/8" diameter.
• Insertion Length: SST models support lengths from 5" to 60"; QST models support lengths from 5" to 36" for diameters of 1/2", 5/8", 11/16", and 3/4".
• Termination Options: Flexible leads (standard 12") or screw terminals (8/32 x 1" welded nickel plated steel studs). Additional protection options include Stainless Steel Armor Cable Lead Protection (Fig. 04C), Right Angle Stainless Steel Armor Cable (Fig. 15C), and flexible stainless steel braided lead protection in straight (Fig. 13C) or right angle (Fig. 17C) configurations.
• Mounting: A mounting flange option is available as Fig. 10C, and threaded post terminal connections are offered under code 20C.

The series supports various voltage codes (120, 240, 380, 480) with wattage determined by the specific configuration. Other thread sizes or lengths may be available upon consultation with Omega sales.

Key Product Differences

The series distinguishes between two primary sheath configurations:

• SST (Single Split-Sheath): Available in all nominal diameters from 3/8" to 1", with maximum insertion lengths up to 60".
• QST (Quad Split-Sheath): Not available in the 3/8" diameter. For supported diameters (1/2" through 3/4"), QST models have a maximum sheath length of 36" and are not offered in the 1" nominal size.

Different termination figures correspond to specific lead protection styles: Fig. 04C provides straight flexible stainless steel armor cable; Fig. 15C offers right angle fitting with flexible stainless steel armor cable (transition length 1-1/2"); Fig. 13C is a straight flexible stainless steel braided lead protection; and Fig. 17C is a right angle fitting with stainless steel braided lead protection.