--- title: Metragator Externally Pressurized Metal Expansion Joint Product Overview description: Episodes Five and Six discuss the externally pressurized MetraGator and HP series compensator. In less than ten minutes, learn almost everything you need to know about these metal expansion joints! image: https://blogs.heattransfersales.com/hubfs/metragator-bg.jpg --- [![HTS_Logo_RGB_and_White](https://blogs.heattransfersales.com/hs-fs/hubfs/HTS_Logo_RGB_and_White.png?width=270&height=81&name=HTS_Logo_RGB_and_White.png "HTS_Logo_RGB_and_White")](http://www.heattransfersales.com) - [Home](https://heattransfersales.com/) - [Products](https://heattransfersales.com/products) - [Manufacturers Represented](https://heattransfersales.com/products) - [Packaged Systems](https://heattransfersales.com/products) - [Customer Service](https://heattransfersales.com/customer-service) - [Parts](https://heattransfersales.com/parts) - [Pump Repair](https://heattransfersales.com/pump-repair) - [Service](https://heattransfersales.com/service) - [Pump'nFlo](https://heattransfersales.com/pump-nflo) - [Resources](https://heattransfersales.com/resources) - [Training](https://heattransfersales.com/training) - [Sustainable System Concepts](https://heattransfersales.com/sustainable-system-concepts) - [Airside HVAC](https://heattransfersales.com/hvac-equipment) - [Plumbing Equipment](https://heattransfersales.com/plumbing-equipment) - [Building Automation](https://heattransfersales.com/building-automation) - [Blog](https://blogs.heattransfersales.com/blog) - [Careers](https://heattransfersales.com/careers) - [About Us](https://heattransfersales.com/about-us) - [History](https://heattransfersales.com/history) - [Privacy Policy](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_f6100e8b535d465f9fb060f60f8049cc.pdf) - [Terms of Use](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_8a108a4c73734c8ca00866bdecf7cb60.pdf) - [Contact](https://heattransfersales.com/contact) ### Topics - Select a Topic ### Stay up to date SUBSCRIBE TO OUR BLOG ### Stay up to date [Metraflex](https://blogs.heattransfersales.com/blog/topic/metraflex) [Compensator](https://blogs.heattransfersales.com/blog/topic/compensator) [Metal Expansion Joints](https://blogs.heattransfersales.com/blog/topic/metal-expansion-joints) [Externally Pressurized Joint](https://blogs.heattransfersales.com/blog/topic/externally-pressurized-joint) # Metragator Externally Pressurized Metal Expansion Joint Product Overview ![Picture of HTS Marketing Team](https://blogs.heattransfersales.com/hubfs/HTS_Symbol_RGB%20(2).png) By [HTS Marketing Team](https://blogs.heattransfersales.com/blog/author/hts-marketing-team) on May, 13 2020 [mailto:?body=https://blogs.heattransfersales.com/blog/metragator-externally-pressurized-metal-expansion-joint-product-overview](mailto:?body=https://blogs.heattransfersales.com/blog/metragator-externally-pressurized-metal-expansion-joint-product-overview) ![MetraGator](https://blogs.heattransfersales.com/hubfs/metragator-bg.jpg) ![metragator-bg](https://blogs.heattransfersales.com/hs-fs/hubfs/metragator-bg.jpg?width=190&name=metragator-bg.jpg)Continuing with our excitement with [Metraflex’s](https://www.metraflex.com/) Essential Product Knowledge… From a Distance mini-series, Episodes Five and Six are a two-part series with loads of information in less than 10 minutes ***combined***. If you have missed any of the previous episodes, you can find them [here](https://blogs.heattransfersales.com/blog), along with some of our takeaways! Episodes Five and Six are hosted by Metraflex’s President, Jim Richter, and discuss the externally pressurized [MetraGator](https://www.metraflex.com/metal-expansion-joints-2/metragator/) and [HP series compensator](https://www.metraflex.com/compensators/model-hp2/) in-depth.   Here are a few of our takeaways: 1. There is the MetraGator, the expansion compensator and the copper compensator. They have identical construction, but the smaller diameters are referred to as compensators and the larger ones, actually pressurized. - The only thing copper on a copper compensator is the copper sweat ends. The rest of it is 100% stainless steel. 2. There is a shipping bar on all these products, copper and steel. This shipping bar has to be strong enough to last through shipping, but weak enough so the contractor can break it off in the field. 3. An o-ring is added to the traveling end and the gap to prevent debris from falling into the bellows, which helps to reduce premature rust damage. - The o-ring is made out of EPDM. - It is most important during the instruction of the building. After that, it’s okay if it falls off, or wears off. 4. The unique feature that makes this an externally pressurized joint is how the flow, the water and the pressure get on the exterior of the bellows. - One side of the bellows is completely exposed to atmosphere, not to the water in the system or the pressure of the system, hence the term, “Externally Pressurized.” - The water ends up on the outside of the bellows on both sides. A bellow that is stabilized from the outside is much more stable than internally pressurized bellows. - Therefore, it can be made longer so that it can have a much bigger stroke. 5. There is a bump on the outside of the piece of equipment. - This bump is a stop that is to prevent over-extension of the joint. - It will prevent the bellows from over-compressing. Watch the two-part series below!   ###### About The Author [More from this author](https://blogs.heattransfersales.com/blog/author/hts-marketing-team) ![](https://blogs.heattransfersales.com/hs-fs/hubfs/HTS_Symbol_RGB%20(2).png?height=100&name=HTS_Symbol_RGB%20(2).png) ###### HTS Marketing Team The HTS Marketing team loves finding new ways to educate our customers! #### Recommended Articles [![Boost Your HVAC System Energy Savings with this Y-Strainer](https://blogs.heattransfersales.com/hubfs/Boost%20Your%20hvac%20system%20energy%20savings%20with%20this%20y-strainer%20(3).png)](https://blogs.heattransfersales.com/blog/boost-your-hvac-system-energy-savings-with-this-y-strainer) ###### [Boost Your HVAC System Energy Savings with this Y-Strainer](https://blogs.heattransfersales.com/blog/boost-your-hvac-system-energy-savings-with-this-y-strainer) - September 29, 2020 [![MetraSeal Pipe Penetration Seal Product Overview](https://blogs.heattransfersales.com/hubfs/metraseal.png)](https://blogs.heattransfersales.com/blog/metraseal-wall-penetration-seal) ###### [MetraSeal Pipe Penetration Seal Product Overview](https://blogs.heattransfersales.com/blog/metraseal-wall-penetration-seal) - July 8, 2020 [![Everything You Need to Know About Delegated Design](https://blogs.heattransfersales.com/hubfs/image-6.png)](https://blogs.heattransfersales.com/blog/everything-you-need-to-know-about-delegated-design) ###### [Everything You Need to Know About Delegated Design](https://blogs.heattransfersales.com/blog/everything-you-need-to-know-about-delegated-design) - June 23, 2020 #### Recommended Articles #### Recommended Articles #### Recommended Articles Search Article ### Popular Posts ### Stay up to date ### Recent Post ### Recent Posts [A Look at Why the Riello Array Has Won So Many Awards](https://blogs.heattransfersales.com/blog/a-look-at-why-the-riello-array-has-won-so-many-awards) - 13 May, 2020 [Replacing Outdated Boilers to Meet New DOE Standards](https://blogs.heattransfersales.com/blog/replacing-outdated-boilers-to-meet-new-doe-standards) - 13 May, 2020 [3 “NEED TO KNOWS” ABOUT DHW SYSTEMS](https://blogs.heattransfersales.com/blog/3-need-to-knows-about-dhw-systems) - 13 May, 2020 [4 Benefits of Switching to a Hydronic HVAC System](https://blogs.heattransfersales.com/blog/4-benefits-of-switching-to-a-hydronic-hvac-system) - 13 May, 2020 [Why Prefabricated Pumping Systems Ease System Design](https://blogs.heattransfersales.com/blog/why-prefabricated-pumping-systems-ease-system-design) - 13 May, 2020 ###### ABOUT THE COMPANY ![HTS_Symbol_RGB](https://blogs.heattransfersales.com/hubfs/HTS_Symbol_RGB.png) ### Heat Transfer Sales, LLC We are proponents of sustainable and efficient hydronic heating and cooling building solutions, which are at the heart of commercial green building. - - - - ### Topics - [Design Engineer Tips (109)](https://blogs.heattransfersales.com/blog/topic/design-engineer-tips) - [General Knowledge (95)](https://blogs.heattransfersales.com/blog/topic/general-knowledge) - [Building Owner Tips (70)](https://blogs.heattransfersales.com/blog/topic/building-owner-tips) - [Pumps (56)](https://blogs.heattransfersales.com/blog/topic/pumps) - [Manufacturer Information (46)](https://blogs.heattransfersales.com/blog/topic/manufacturer-information) - [Boilers and Water Heaters (40)](https://blogs.heattransfersales.com/blog/topic/boilers-and-water-heaters) - [Efficiency (22)](https://blogs.heattransfersales.com/blog/topic/efficiency) - [Training (22)](https://blogs.heattransfersales.com/blog/topic/training) - [Webinars (18)](https://blogs.heattransfersales.com/blog/topic/webinars) - [Customer Service (17)](https://blogs.heattransfersales.com/blog/topic/customer-service) - [Energy Savings (14)](https://blogs.heattransfersales.com/blog/topic/energy-savings) - [Air Curtains (13)](https://blogs.heattransfersales.com/blog/topic/air-curtains) - [HVAC (12)](https://blogs.heattransfersales.com/blog/topic/hvac) - [Metraflex (12)](https://blogs.heattransfersales.com/blog/topic/metraflex) - [infrared Heating (12)](https://blogs.heattransfersales.com/blog/topic/infrared-heating) - [Products (10)](https://blogs.heattransfersales.com/blog/topic/products) - [HVAC Design Tools (9)](https://blogs.heattransfersales.com/blog/topic/hvac-design-tools) - [PDH Credits (9)](https://blogs.heattransfersales.com/blog/topic/pdh-credits) - [Parts (9)](https://blogs.heattransfersales.com/blog/topic/parts) - [Hydronic (8)](https://blogs.heattransfersales.com/blog/topic/hydronic) - [Filtration (7)](https://blogs.heattransfersales.com/blog/topic/filtration) - [Boilers (6)](https://blogs.heattransfersales.com/blog/topic/boilers) - [Taco (6)](https://blogs.heattransfersales.com/blog/topic/taco) - [Piping (4)](https://blogs.heattransfersales.com/blog/topic/piping) - [Raypak (4)](https://blogs.heattransfersales.com/blog/topic/raypak) - [Schwank (4)](https://blogs.heattransfersales.com/blog/topic/schwank) - [Valves (4)](https://blogs.heattransfersales.com/blog/topic/valves) - [Variable Frequency Drives (4)](https://blogs.heattransfersales.com/blog/topic/variable-frequency-drives) - [Water (4)](https://blogs.heattransfersales.com/blog/topic/water) - [Water Purification (4)](https://blogs.heattransfersales.com/blog/topic/water-purification) - [Burners (3)](https://blogs.heattransfersales.com/blog/topic/burners) - [Commercial Boiler (3)](https://blogs.heattransfersales.com/blog/topic/commercial-boiler) - [Cooling Towers (3)](https://blogs.heattransfersales.com/blog/topic/cooling-towers) - [Green Building Design and Equipment (3)](https://blogs.heattransfersales.com/blog/topic/green-building-design-and-equipment) - [Pump'nFlo (3)](https://blogs.heattransfersales.com/blog/topic/pumpnflo) - [Riello (3)](https://blogs.heattransfersales.com/blog/topic/riello) - [About us (2)](https://blogs.heattransfersales.com/blog/topic/about-us) - [Expansion Joints (2)](https://blogs.heattransfersales.com/blog/topic/expansion-joints) - [Outdoor Dining (2)](https://blogs.heattransfersales.com/blog/topic/outdoor-dining) - [Pump Selection (2)](https://blogs.heattransfersales.com/blog/topic/pump-selection) - [Technician Tips (2)](https://blogs.heattransfersales.com/blog/topic/technician-tips) - [humidification (2)](https://blogs.heattransfersales.com/blog/topic/humidification) - [pure humidifier (2)](https://blogs.heattransfersales.com/blog/topic/pure-humidifier) - [AERCO (1)](https://blogs.heattransfersales.com/blog/topic/aerco) - [Air Release Valve (1)](https://blogs.heattransfersales.com/blog/topic/air-release-valve) - [Anchor Load Calculations (1)](https://blogs.heattransfersales.com/blog/topic/anchor-load-calculations) - [Chillers (1)](https://blogs.heattransfersales.com/blog/topic/chillers) - [Closed-Coupled Design (1)](https://blogs.heattransfersales.com/blog/topic/closed-coupled-design) - [Commercial HVAC (1)](https://blogs.heattransfersales.com/blog/topic/commercial-hvac) - [Commercial Range (1)](https://blogs.heattransfersales.com/blog/topic/commercial-range) - [Compensator (1)](https://blogs.heattransfersales.com/blog/topic/compensator) - [Cooling (1)](https://blogs.heattransfersales.com/blog/topic/cooling) - [Delegated Design (1)](https://blogs.heattransfersales.com/blog/topic/delegated-design) - [Digital Gas Heater (1)](https://blogs.heattransfersales.com/blog/topic/digital-gas-heater) - [Expansion Tanks (1)](https://blogs.heattransfersales.com/blog/topic/expansion-tanks) - [Externally Pressurized Joint (1)](https://blogs.heattransfersales.com/blog/topic/externally-pressurized-joint) - [Guide Spacing Requirements (1)](https://blogs.heattransfersales.com/blog/topic/guide-spacing-requirements) - [Heaters (1)](https://blogs.heattransfersales.com/blog/topic/heaters) - [Hospitals (1)](https://blogs.heattransfersales.com/blog/topic/hospitals) - [LEED (1)](https://blogs.heattransfersales.com/blog/topic/leed) - [LPD Strainer (1)](https://blogs.heattransfersales.com/blog/topic/lpd-strainer) - [Make-up Water (1)](https://blogs.heattransfersales.com/blog/topic/make-up-water) - [Metal Expansion Joints (1)](https://blogs.heattransfersales.com/blog/topic/metal-expansion-joints) - [MetraPak (1)](https://blogs.heattransfersales.com/blog/topic/metrapak) - [Metraloop (1)](https://blogs.heattransfersales.com/blog/topic/metraloop) - [New Product (1)](https://blogs.heattransfersales.com/blog/topic/new-product) - [PAX Series (1)](https://blogs.heattransfersales.com/blog/topic/pax-series) - [Pipe Penetration Seal (1)](https://blogs.heattransfersales.com/blog/topic/pipe-penetration-seal) - [Potable Water Systems (1)](https://blogs.heattransfersales.com/blog/topic/potable-water-systems) - [Project Files (1)](https://blogs.heattransfersales.com/blog/topic/project-files) - [Pump collector (1)](https://blogs.heattransfersales.com/blog/topic/pump-collector) - [Quiz (1)](https://blogs.heattransfersales.com/blog/topic/quiz) - [Refrigerant (1)](https://blogs.heattransfersales.com/blog/topic/refrigerant) - [Restaurant Patios (1)](https://blogs.heattransfersales.com/blog/topic/restaurant-patios) - [Riser Anchor Clamp (1)](https://blogs.heattransfersales.com/blog/topic/riser-anchor-clamp) - [SST Series (1)](https://blogs.heattransfersales.com/blog/topic/sst-series) - [Steam (1)](https://blogs.heattransfersales.com/blog/topic/steam) - [SuctionDiffuserFlex (1)](https://blogs.heattransfersales.com/blog/topic/suctiondiffuserflex) - [System Feed Units (1)](https://blogs.heattransfersales.com/blog/topic/system-feed-units) - [VRF (1)](https://blogs.heattransfersales.com/blog/topic/vrf) - [VaneFlex (1)](https://blogs.heattransfersales.com/blog/topic/vaneflex) - [Vertical Inline (1)](https://blogs.heattransfersales.com/blog/topic/vertical-inline) - [Y-Strainer (1)](https://blogs.heattransfersales.com/blog/topic/y-strainer) - [YANMAR (1)](https://blogs.heattransfersales.com/blog/topic/yanmar) - [seismic breakaway hanger (1)](https://blogs.heattransfersales.com/blog/topic/seismic-breakaway-hanger) - [superTube (1)](https://blogs.heattransfersales.com/blog/topic/supertube) see all [![New Call-to-action](https://no-cache.hubspot.com/cta/default/715354/d9a35e17-d3c8-44b5-91e0-47a3bcfea5f0.png)](https://cta-redirect.hubspot.com/cta/redirect/715354/d9a35e17-d3c8-44b5-91e0-47a3bcfea5f0) #### Submit a Comment ### Get latest articles directly in your inbox, stay up to date SUBSCRIBE TO OUR BLOG **Our Location** Headquarters 4101 Beechwood Drive, Greensboro, NC 27410 [Get Directions](https://www.google.com/maps/place/4101+Beechwood+Dr,+Greensboro,+NC+27410/@36.0544034,-79.9484879,17z/data=!3m1!4b1!4m5!3m4!1s0x8853051e63c99b6d:0x24b2c5a3927d7634!8m2!3d36.0544034!4d-79.9462992) **Contact Us** 336.294.3838 [info@heattransfersales.com](mailto:info@heattransfersales.com) [![Untitled design - 2020-11-19T112748.776](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112748.776.png?width=24&name=Untitled%20design%20-%202020-11-19T112748.776.png)](https://www.linkedin.com/company/heat-transfer-sales-of-the-carolinas-inc) [![Untitled design - 2020-11-19T112815.271](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112815.271.png?width=24&name=Untitled%20design%20-%202020-11-19T112815.271.png)](https://www.facebook.com/HeatTransferSales/) [![Untitled design - 2020-11-19T112835.473](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112835.473.png?width=24&name=Untitled%20design%20-%202020-11-19T112835.473.png)](https://twitter.com/htscarolinas) [![Untitled design - 2020-11-19T112859.003](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112859.003.png?width=24&name=Untitled%20design%20-%202020-11-19T112859.003.png)](https://www.youtube.com/channel/UCX51QZbsuqCtu2PxtW9jMEg) - [Home](https://heattransfersales.com/) - [Products](https://heattransfersales.com/products) - [Manufacturers Represented](https://heattransfersales.com/products) - [Packaged Systems](https://heattransfersales.com/products) - [Customer Service](https://heattransfersales.com/customer-service) - [Parts](https://heattransfersales.com/parts) - [Pump Repair](https://heattransfersales.com/pump-repair) - [Service](https://heattransfersales.com/service) - [Pump'nFlo](https://heattransfersales.com/pump-nflo) - [Resources](https://heattransfersales.com/resources) - [Training](https://heattransfersales.com/training) - [Sustainable System Concepts](https://heattransfersales.com/sustainable-system-concepts) - [Airside HVAC](https://heattransfersales.com/hvac-equipment) - [Plumbing Equipment](https://heattransfersales.com/plumbing-equipment) - [Building Automation](https://heattransfersales.com/building-automation) - [Blog](https://blogs.heattransfersales.com/blog) - [Careers](https://heattransfersales.com/careers) - [About Us](https://heattransfersales.com/about-us) - [History](https://heattransfersales.com/history) - [Privacy Policy](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_f6100e8b535d465f9fb060f60f8049cc.pdf) - [Terms of Use](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_8a108a4c73734c8ca00866bdecf7cb60.pdf) - [Contact](https://heattransfersales.com/contact) ![HTS_Logo_Symbol_White_CMYK](https://blogs.heattransfersales.com/hs-fs/hubfs/HTS_Logo_Symbol_White_CMYK.png?width=52&height=52&name=HTS_Logo_Symbol_White_CMYK.png "HTS_Logo_Symbol_White_CMYK") All content © 2020, Heat Transfer Sales