
Closure & measurement
Spades / Paddle Blinds
A spade is a solid line blank with a handle, installed between flanges for a specified isolation condition. It is used with a separately identified matching spacer arrangement.

Closure & measurement
A ring spacer is the open component of a separate spade-and-spacer arrangement. Its bore permits the intended flow path while maintaining the specified flange-joint spacing.
A line-blank spacer is not a general-purpose washer or a lap-joint backing flange. Match its bore, thickness and gasket-contact surfaces to the associated spade and flange assembly. The standard, material and marking requirements must be stated for the actual service.
Compare flange typesConfirm the spacer and spade arrangement with the intended gasket and bolt selection. Do not insert an arbitrary ring merely to occupy the space left by a removed blank.
Specify the flow opening and any handle identification under the project standard. Material traceability and surface finish remain relevant even though the component has an open centre.
Define Ring Spacers as part of the complete joint. These fields identify required engineering data; they are not universal dimensions or a declaration of available sizes.
| Parameter / designation | Technical information | Selection requirement |
|---|---|---|
| Nominal size and bore | State the nominal connection size separately from the actual bore or pipe outside diameter. | A matching size label does not establish matching internal geometry. |
| Outside diameter and thickness | Identify the finished flange diameter, minimum thickness and any hub or collar projection. | Include the drawing datum and units for replacement measurements. |
| Bolt circle and holes | Record pitch-circle diameter, hole quantity, hole diameter and any special orientation. | Check against the mating flange; do not infer a bolt pattern from pressure class alone. |
| Gasket-contact surfaces | Specify face form, seating dimensions and surface finish on the assembled joint. | Include gasket designation; a visually similar surface is not evidence of compatibility. |
| Pipe-side interface | Identify weld preparation, socket, thread, collar or other attachment geometry as applicable. | Provide pipe schedule/wall thickness and the connection-specific standard. |
| Design conditions | State design pressure, minimum/maximum temperature, fluid and mechanical loads. | Pressure class is not a pressure value in bar or psi. Use the material-specific rating basis. |
Compare Ring Spacers with the related forms or references below. A related product is not necessarily a permissible substitute.
| Related product / reference | Distinction | Check before selection |
|---|---|---|
| Spades / Paddle Blinds | A spade is a solid line blank with a handle, installed between flanges for a specified isolation condition. It is used with a separately identified matching spacer arrangement. | Nominal size, rating, thickness and applicable standard |
| Spectacle Blinds | A spectacle blind joins a solid blank and an open ring with a connecting bridge. One side or the other is positioned in the flange joint to define the line condition. | ASME B16.48 where applicable, with edition and scope confirmed |
| Loose Flanges | A loose flange is a separate backing component working with a collar, lapped end or stub end. It transfers bolt load while the companion component forms the pipe-side seating interface. | Collar or stub-end designation and drawing |
Define acceptance requirements for Ring Spacers in the purchase order. Required examinations and documents depend on the material, design and project specification.
| Review stage | Information to confirm | Order requirement |
|---|---|---|
| Material identity and traceability | Specification, grade, heat/lot identification and the required material certificate. | Agree documentation and marking before manufacture; visual appearance cannot verify alloy identity. |
| Dimensional verification | Critical dimensions from the selected standard or controlled drawing. | Identify inspection points, tolerances, units and drawing revision. |
| Surface and end condition | Gasket-contact surface, attachment end, edges and any coating exclusions. | State finish and visual acceptance criteria; agree protection of machined surfaces. |
| Supplementary examinations | Any specified PMI, NDE, hardness, impact, corrosion or other tests. | Define the method, sampling and acceptance criteria; tests are not automatically included. |
| Assembly compatibility | Adjoining components, weld or mechanical interface and project service conditions. | Design approval and correct assembly remain separate from a dimensional inspection report. |
| Packing and order release | Quantity, identification, surface protection, documents and delivery destination. | Agree preservation, packaging and release requirements with the order. |
Specification checklist
Availability, dimensions and pressure-temperature suitability are confirmed against your complete enquiry.
| Item | Requirement |
|---|---|
| Standard | ASME B16.48 where applicable or the approved project drawing |
| Opening | Nominal size, bore and pipe-interface requirements |
| Pairing | Spade designation, thickness and gasket arrangement |
| Identification | Handle, marking, material and inspection documentation |
| Material & quantity | Exact material designation, quantity and required certification or inspection documents |
Application context
Related connections

Closure & measurement
A spade is a solid line blank with a handle, installed between flanges for a specified isolation condition. It is used with a separately identified matching spacer arrangement.

Closure & measurement
A spectacle blind joins a solid blank and an open ring with a connecting bridge. One side or the other is positioned in the flange joint to define the line condition.

Mechanical connections
A loose flange is a separate backing component working with a collar, lapped end or stub end. It transfers bolt load while the companion component forms the pipe-side seating interface.