Rod Seals

Rod or Gland Seals are available in a range of sizes and styles

The function of a rod seal, otherwise known as a gland seal, is to prevent pressurised fluid leaking out of the system while a rod reciprocates through its travel past the seal. It is often the most critical seal in a system, since it seals the internal fluid or gas from escape into the surrounding environment. While leakage past a piston seal will affect its efficiency, the system fluid or gas remains contained in the system. However, with a rod or gland seal, failure will allow external leakage, and it should be paired with an appropriate wiper and gland housing design to ensure correct operation.

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The function of a rod seal is to contain pressure within the system without leakage out of the gland and therefore allow maximum mechanical effort to be applied to moving the piston along the bore of a cylinder. They can be used either hydraulically or pneumatically, with appropriate seal designs for each system, and application. The seal is intended to prevent leakage across the moving ram rod surface diameter and thus contain the system fluid or gas; pressure can either be applied in one direction only (single acting) or from either direction (double acting), to drive the ram that the piston is fixed to both in and out. Individual seal profile designs show specific behaviours and performance, which need to be in line with the application´s requirement. The material chosen will also influence the choice of seal profile. When determining the best seal design and material for a particular application, consideration needs to be given to the pressures expected, whether a single or double acting seal is required, the friction losses acceptable, and whether energisation is necessary.

The design of the gland is important, as this will dictate what types of seal profile and material can be used in the application. Many high pressure systems require very stiff, robust seals and the associated guide rings to control the action of the ram rod. In such cases, it is usual to split the gland into several parts so that the seals do not need to be compressed into the gland and snapped into place, but can simply be assembled in place and the gland head bolted on with securing fixings once fully built up.

Because our Rod Seals can be CNC machined to bespoke sizes, we can add material to compensate for worn or re-manufactured rod or gland conditions, and help restore the original performance of used equipment as well as provide components for new build designs.

View our standard profiles for general guidance, you will find our standard Rod Seals listed as S101, S102, S102R, S103, S104, S104R, S105, S106, S107 and S108 which all conform to BS ISO 5597:2010 & BS 5751:1987 (R05). S109 conforms to BS6984:1998 & BS ISO 7425-1:2002 & BS ISO 7425-2:1989. S116, S216, S117 and S117R conform to BS ISO 5597:2010 & BS 5751:1978 (R05).  S121, S125, S139 and S141 conform to BS ISO 5597:2010 & BS 5751:1978 (R05), S124, S129, S138 and S142 conform to BS 6984:1998 & BS ISO 7425-1:2002 & BS ISO 7425-2:1989.  These styles can be rapid manufactured in a variety of different materials depending on the application, and we also stock standard products for immediate shipment. Please contact us to discuss your specific requirements so that we may advise on the best solution for your application.

Rod Seal profile range from Martins Rubber. Available in a range of materials and sizes

Rod Seal profile range from Martins Rubber. Available in a range of materials and sizes