310101e Mounting and Support Hardware

Objectives of Mounting and Support Hardware

• Location Considerations: Describe and explain limitations of hardware location.

• Identification of Fasteners: Identify commonly used fasteners in mounting and support hardware.

Importance of Mounting Instruments

• Essential for accurate measurements of processes.

• Guidelines for Installing Instruments:

  • Position near the process in a horizontal alignment.

  • Minimize temperature differences between instrument and process.

  • Avoid vibrations and external corrosive contacts.

  • Ensure easy access for maintenance.

  • Aim to minimize plugging.

Mounting Methods

Direct Mounting

• In immediate vicinity of the process.

• Methods include:

  • Welded Thread-O-Let or Welded Flange.

• Important Note: The connection should not directly face process impacts.

Close-Coupled Mounting

• Advantages:

  • Lower installation costs.

  • Reduced risks of plugging and freezing.

  • Minimizes leakage and low emissions.

  • Enhances maintenance integrity, easier winterization, and heat tracing.

Remote Mounting

• This method is used when direct mounting is impractical due to:

  • Inaccessibility of the instrument.

  • Safety concerns.

  • Environmental conditions.

  • Engineering specifications.

• Use of Impulse Lines:

  • Must be protected from vibration, shock, temperature, and physical damage.

Remote Mounting Considerations

• Install instruments no more than 1.5 m above ground.

• Avoid placing instruments in walkways and ensure they do not pose tripping hazards.

• Instruments should be mounted vertically, level, and stable.

• Protect drain ports from dust, insects, and water.

• Instruments should not be mounted on handrails or connected to floor gratings.

In-Line Mounting

• Process fluid or gas flows through the instrument.

• Best Practices:

  • Check process flow direction.

  • Ensure uniform flange and gasket contact.

  • Tighten flanges in a crisscross pattern to maintain even pressure.

  • Locate pressure taps in straight runs.

Types of Mounting Hardware

Cable Mount Instrument Stands

• Suitable for both horizontal and vertical installations.

• Must be installed before pipe insulation.

U-Bolt Instrument Stands

• Requires two U-bolts for securing to walls or floors.

• Typically made from ¼” steel plates.

Mounting Hardware Examples

• Yokogawa and Rosemount transmitters offer various mounting styles suitable for vertical and horizontal pipes.

Support Hardware

Types

• Electrical Conduit:

  • Metal conduit provides grounding and shielding against shocks and interference.

  • Plastic conduit offers chemical resistance but needs bonding conductors for grounding.

Cable Trays

• Designed for routing cables efficiently and can support UV protection for cables exposed to sunlight.

• Metal trays offer limited electrostatic interference shielding due to multiple cables.

Tubing Support

• Prevent sagging and can support small valves using threaded fasteners.

Fasteners in Mounting and Support Hardware

Fastener Terminology

• Screw Threads Terminology:

  • Major diameter, minor diameter, pitch of screws, root, crest, and thread angle are essential concepts for understanding fasteners.

• Types of Threads:

  • Coarse Threads (UNC), Fine Threads (UNF), and Extra Fine Threads (UNEF).

Types of Threaded Fasteners

• Cap Screws: External threads, mated with female or own threads.

• Stud Bolts: Have external threads and use two nuts—for fastening.

Bolt Grades and Strength Chart

Key Properties

• Grade 2: Low carbon steel, proof load of 33,000 psi.

• Grade 5: Medium carbon steel, proof load of 85,000 psi.

• Grade 8: Medium carbon alloy steel, proof load of 120,000 psi.

Metric Property Classes

• Class 4.6, 4.8, 5.8, 8.8, 9.8, 10.9, with respective tensile strength and increases in strength per class.

Masonry Anchors

Types and Installation

• Types:

  • Expanding anchors and friction force anchors.

• Installation Guidelines:

  • Ensure anchors are rated for static and dynamic loads, with specific distance requirements.

Conclusion

• Review the concepts covered, focusing on the understanding of mounting and support hardware principles, methods, fasteners, and their applications through the provided self-test.