HVAC systems depend on accurate temperature and pressure readings to run efficiently. Mac-Weld threaded and socket weld thermowells protect sensors in chilled water, hot water and steam loops, and allow instruments to be removed without draining the system. Gauge siphons shield pressure gauges from steam, while needle valves and 2 valve manifolds isolate transmitters and switches for easy service. Every part is made in house, quality checked and available in standard and custom sizes to fit new builds and retrofits.

Water and wastewater plants need rugged instrumentation that stands up to corrosive, solids-laden flows. Mac-Weld orifice plates and meter runs support accurate flow measurement, while flow meter grounding rings protect magnetic flow meter readings. Stainless steel thermowells, needle valves and manifolds isolate instruments for safe maintenance, and level chambers allow external level measurement on tanks and clarifiers.

Refineries and petrochemical plants run at high temperatures and pressures where instrument failure is not an option. Mac-Weld flanged, vanstone and weld-in thermowells are calculated to ASME PTC 19.3 TW-2016 using our V-MAC software, and are available NACE compliant with full NDT options. Orifice plates, spectacle blinds, bleed rings, double block and bleed valves and level chambers complete the package for critical service, made in with CRN approvals available on request.

Tank farms and terminals need reliable level, temperature and flow data to store and transfer product safely. Mac-Weld level chambers mount radar and other level instruments outside the tank, allowing live maintenance and isolation away from turbulence. Thermowells protect temperature sensors, while meter runs, orifice plates and spectacle blinds support custody transfer and line isolation. All chambers are built to ASME B31.3 with traceable materials and hydro tested before shipping, with NDT and customer inspection options available to order.

Environmental and emissions control systems require accurate measurement to meet regulations. Mac-Weld supplies thermowells and protection tubes for stack and scrubber temperatures, orifice plates for gas and liquid flow, and injection and sample quills for chemical dosing and sampling. Corrosion-resistant materials such as Hastelloy, Monel and Titanium, plus PTFE and other coatings, extend service life in harsh conditions. Every part is made in house and quality checked before shipping.

Food and beverage processing demands hygienic, food-safe equipment that is easy to clean and maintain. Mac-Weld tri-clamp sanitary thermowells are polished to an 8-12 micro inch R/A finish and connect quickly to sanitary process lines, letting temperature sensors be removed without opening the process. Stainless steel needle valves, gauge siphons and flush rings support pressure measurement and cleaning in brewing, dairy and bottling plants.

Medical and healthcare facilities rely on clean, precise process equipment for sterilization, pharmaceutical-grade water, medical gases and building systems. Mac-Weld tri-clamp sanitary thermowells with an 8-12 micro inch R/A finish protect sensors in autoclaves, clean steam and purified water lines. Stainless steel needle valves, manifolds and gauge siphons isolate and protect pressure instruments for safe calibration. All parts are made in house, quality checked and tested to code before shipping.

Agriculture operations, from grain drying and storage to fertilizer and irrigation systems, need durable instruments that handle dust, moisture and chemicals. Mac-Weld thermowells protect temperature sensors in dryers, bins and process lines, while gauge siphons, needle valves and manifolds protect and isolate pressure instruments. Orifice plates support accurate flow control in water, ammonia and chemical lines. Fabricated in-house from a range of alloys, including carbon steel, stainless steel, and exotic alloys, to suit your application.

Upstream, midstream and downstream oil and gas operations count on Mac-Weld for rugged flow and temperature hardware. Our orifice plates, meter runs, orifice flange unions and RTJ holders support accurate gas and liquid measurement, while spectacle blinds and double block and bleed valves provide safe isolation for maintenance and pigging. NACE compliant thermowells are designed to spec using wake frequency calculated with V-MAC. CRN approved parts in flange ratings up to 2500# are made in house and tested to code before shipping.

Mining and mineral processing push instruments to their limits with abrasive slurries, vibration and extreme temperatures. Mac-Weld heavy-duty thermowells and protection tubes shield sensors in kilns, smelters and leach circuits, with tapered and helical shanks to resist vibration. Orifice plates, flow meter grounding rings, needle valves and manifolds support flow and pressure measurement. Wear- and corrosion-resistant alloys and coatings are available, and quality checked and tested to code.

Pharmaceutical manufacturing requires sanitary, traceable equipment that supports strict quality control. Mac-Weld tri-clamp thermowells polished to an 8-12 micro inch R/A finish protect sensors in reactors, clean-in-place systems and purified water lines. Stainless steel and Hastelloy flush rings, needle valves and manifolds allow instruments to be calibrated without breaking the process. Every part is made in house with certified, traceable materials under an ISO 9001:2015 quality system.

Power plants depend on accurate temperature, flow and pressure readings to run safely and efficiently. Mac-Weld thermowells for steam and feedwater lines are designed to ASME PTC 19.3 TW-2016 with our V-MAC wake frequency software. Orifice plates and meter runs measure flow, finned gauge siphons protect instruments from steam and seal pots isolate transmitters. Level chambers built to ASME B31.1 or B31.3 monitor drums and heaters. Every part is made in house, quality checked and tested to code before shipping, with full NDT options available.

Chemical plants handle corrosive and hazardous fluids that call for the right materials and reliable isolation. Mac-Weld flush rings let diaphragm seal transmitters be calibrated, vented and purged without removing them from the line. Bleed rings, thermowells, orifice plates and needle valves are available in Hastelloy, Monel, Inconel, Titanium, Super Duplex and Kynar, with PTFE, electroless nickel and other coatings to extend service life.

Gas, water and district energy utilities need dependable measurements across large distribution networks. Mac-Weld orifice plates, meter runs and orifice flange unions support accurate flow metering, while thermowells and gauge siphons protect temperature and pressure instruments. Needle valves and manifolds isolate transmitters for safe field calibration. With CRN approvals on request and in-house manufacturing, Mac-Weld delivers precision, quality parts with on-time delivery for new installations and maintenance projects alike.

Pulp and paper mills combine high-temperature steam, harsh bleaching chemicals and abrasive stock that wear out instruments quickly. Mac-Weld thermowells protect sensors in digesters, recovery boilers and dryer sections, and finned gauge siphons shield pressure gauges from steam. Flush rings, orifice plates and needle valves support flow and pressure measurement in chemical lines. Corrosion-resistant alloys such as Super Duplex and Hastelloy are available, and every part is made in house, quality checked and tested to code before shipping.

Hydraulic and fluid power systems in mobile, industrial and test equipment operate at high pressures where leaks and gauge failures cost time and money. Mac-Weld needle valves and gauge root valves are rated up to 6000 psig, with a backseat stop spindle that prevents blowout and non-rotating trim for bubble tight shut-off. 2, 3 and 5 valve manifolds mount pressure transmitters and switches, and gauge siphons reduce gauge shock. A stainless steel pin keeps the gland body secure, and a dust cap keeps out contaminants.