Description
Product Overview
The Spirax Sarco HM34 Series is a carbon steel inverted bucket steam trap. It discharges condensate from horizontal steam systems to prevent waterlogging and maintain thermal efficiency. The trap incorporates an internal strainer as standard and is rated for saturated steam service up to 32 bar g.
Key Features
- Manufactured with a carbon steel body (forged steel for 1/2” and 3/4” sizes, cast steel for 1” size).
- Integral stainless steel strainer screen fitted as standard.
- Designed specifically for horizontal pipeline installations.
- Complies with the requirements of the Pressure Equipment Directive 2014/68/EU.
- Available with certification to EN 10204 2.2 upon request.
Technical Specifications
| Parameter | Value |
|---|---|
| Sizes | 1/2”, 3/4”, 1” (DN15, DN20, DN25) |
| Pipe Connections | Screwed BSP T Rp (ISO 7-1) or NPT; Socket weld ends BS 3799 Class 3000; Flanged EN 1092 PN40, ANSI 150, ANSI 300 |
| Body Design Conditions | PN40 |
| PMA (Maximum Allowable Pressure) | 40 bar g @ 120 °C (580 psi g @ 248 °F) |
| TMA (Maximum Allowable Temperature) | 300 °C (572 °F) |
| Minimum Allowable Temperature | -10 °C (14 °F) |
| PMO (Maximum Operating Pressure) | 32 bar g (464 psi g) for saturated steam |
| TMO (Maximum Operating Temperature) | 300 °C (572 °F) |
| Minimum Operating Temperature | 0 °C (32 °F) |
| Maximum Cold Hydraulic Test Pressure | 60 bar g (870 psi g) |
Maximum Differential Pressure (ΔPMX)
| Size | 4 bar (58 psi) | 8.5 bar (123 psi) | 12 bar (174 psi) | 20 bar (290 psi) | 32 bar (464 psi) |
|---|---|---|---|---|---|
| DN15 - 1/2” | HM34/8 | HM34/7 | HM34/6 | HM34/5 | HM34/4 |
| DN20 - 3/4” | HM34/10 | HM34/8 | HM34/7 | HM34/6 | HM34/5 |
| DN25 - 1” | HM34/12 | HM34/10 | HM34/8 | HM34/6 | HM34/5 |
Materials
| Part | Material | Specification |
|---|---|---|
| Cover (1/2”, 3/4”) | Forged steel | 1.0460 (C22.8) |
| Cover (1”) | Cast steel | 1.0619 +N |
| Body | Cast steel | 1.0619 +N |
| Bucket | Stainless steel | BS 1449 304 S31 |
| Valve guide plate | Stainless steel | BS 1449 304 S11 |
| Cover gasket | Reinforced exfoliated graphite | |
| Valve seat | Stainless steel | AISI 431 |
| Valve | Stainless steel | AISI 440B |
| Valve lever | Stainless steel | BS 1449 321 S31 |
| Strainer screen | Stainless steel | ASTM A240 316L |
| Strainer cap | Steel | 1.0460 (C22.8) |
Applications
- Steam systems (Group 2 fluids)
- Air systems
- Water and condensate systems
Installation Notes
The trap must be installed with the body upright so that the bucket rises and falls vertically. The inlet and outlet connections should be in a horizontal plane, with the trap installed below the drain point to maintain a water seal around the open end of the bucket. A small drop leg (typically 150 mm) should precede the trap.
If the trap must be installed at a higher point than the drainage point, a small bore riser into a ‘U’ seal should be used, and a check valve should be fitted before the trap to prevent the loss of the internal water seal. Inverted bucket steam traps do not permit rapid release of air; on process applications, a separate external air vent is required in parallel.