Logic Caps
3.3.10. Logic Caps
Hydraulic and chemical distribution equipment includes dedicated MQC plates, known as logic caps (see Figure 3-12), which provide the ability to redirect services by replacing an outboard MQC plate with an ROV. Logic caps provide the flexibility to modify distribution of hydraulic or chemical services due to circuit failures or changes in system requirements.
The logic cap consists of stab plate mounted hydraulic couplers con-
nected to HFL tubing and plumbed accordingly to suit the application.
Logic caps meet the following minimum requirements:
• They are always used for direct or manifold services in lieu of valves
when possible.
• Designed for 15 years.
• Rated to maximum 5000 psi.
• Redundant LP supplies (e.g., LP1 and LP2) are in separate logic caps on
separate sides of the frame, where possible.
• High-pressure (HP) supplies must be routed through a logic cap.
• Redundant HP supplies (e.g., HP1 and HP2) also must be in separate
logic caps on separate sides of the frame, and in the same logic cap with
a corresponding low-pressure (LP) circuit (i.e., HP1 and LP1 will be
routed to same logic cap where possible).
• All chemical and annulus vent lines are distributed through a logic cap.
• Chemical tubes dedicated for step-out connections are not required to
pass through logic caps.
• The logic cap configuration does not allow cross flow between trees.
• Logic caps are ROV installable and retrievable. Grab rails are provided to
assist in ROV operations.
• All features conform to field wide standard designs in order to facilitate
interchangeability and to minimize tooling.
• Logic cap utilization is based on the following priority list:
• Hydraulic services;
• Methanol (or other hydrate mitigation chemical) distribution;
• Corrosion inhibitor (CI);
• Asphaltene dispersant/inhibitor;
• Other chemicals as defined by project team.
