Calibration Lab Locations Trescal provides instrument services in all U.S. AMETEK has 17,000 colleagues at more than 150 operating locations, and a global network of sales, service and support locations in 30 countries around the world.Calibration Lab. Is a leading global manufacturer of electronic instruments and electromechanical devices with annual sales of approximately 5 billion. The Ametek Sensor, Test & Calibration (STC) family boasts some of the strongest brands in Test & Measurement. Ametek provides pressure, temperature, and process-measuring equipment and calibrators for professionals working across a range of industries including innovative and reliable products from Ametek-Jofra, Chatillon, U.S.
Ametek Pk Lab Master Plus A SuitableA calibrated calibration has the effective area determined via calibration against a gauge for which the effective area or generated pressure is already known. Mass, length) plus a suitable model. A fundamental calibration involves having the effective area of the gauge determined using only measurements of the SI base units (e.g.Means, such as a differential pressure meter are included to identify the time when a pressure balance between the two pressure generating components has been achieved at the reference levels of both the test and reference units. To use this technique, identical piston and cylinders are placed in identical mountings with the output pressures connected. The overall area of the piston and cylinder assembly is then computed using an appropriate mathematical model.This technique is used primarily by national standards laboratories, such as the National Institute of Standards and Technology that are responsible for establishing reference measurements for a larger group such as the United States.3.1.2 Calibrated Characterization of Deadweight TestersThe calibrated characterization of deadweight testers involves the transfer of effective areas of one piston and cylinder to another utilizing pressure based cross-float techniques. Depending upon the severity of the departure of the piston surface from true cylindricity, an average radius of the piston and cylinder may be calculated, or more sophisticated approaches including distortion of the piston by the applied pressure and thermal expansion of the piston can be applied. Pistons of unusual shape are not normally characterized using this technique.Once a set of dimensional measurements has been performed on both the piston and cylinder, there are several ways in which the area of both the piston and cylinder can be specified. Depending upon the shape of both the piston and the cylinder and the support structure for the mass loading mechanism, the detailed dimensional characterization is usually confined to that part of the piston that is inside the cylinder during normal operation.Master weights with known mass are used on both the test and master piston and cylinders. Each of the master columns contains a master piston of a single range (0.01,0.020.05,0.1in2) to minimize disassembly after calibration. We will use for purposes of illustration, the equipment that is used within the AMETEK Pressure Standards Laboratory.3.2.1 Hydraulic Piston-Cylinder Deadweight TestersThe equipment, as illustrated on Figure 3-1, consists of four identical column assemblies to hold the master piston and cylinders and one identical column to hold the piston and cylinder under test. 3.2 Test Equipment for Pressure Standards LaboratoryMany different combinations and assemblies of equipment may be utilized with varying degrees of uncertainty of measurement (See paragraph2.2). This technique is used primarily by industry and calibration laboratories.The reference or master pressure generating units (Piston-Cylinder & Weights) are usually tested at a standards laboratory ( AMETEK masters are tested at NIST).![]() The pressure differential between the master and the test piston-cylinders is indicated on the null meter.5. Both pistons are rotated approximately 30 RPM and the cross-over valve is closed.4. Pressure is applied to both the unknown piston and cylinder and the master piston and cylinder to bring both pistons to position in the middle of the vertical float range.3. The unknown piston and cylinder is cleaned and installed in the test column.2. The pressure balance is illustrated by the following equation:Au = Area of the unknown piston and cylinderAm = Area of the master piston and cylinderThe procedure for calibration of a piston and cylinder with an unknown effective area consists of the following steps:1. A crossover valve permits interconnection of the output pressure generating components. Ametek Pk Lab Master Free And SensitiveThe steps 2-6 are repeated for each required test pressure.8. This test assures that the piston was free and sensitive when the pressure balance was measured.7. A small tare weight is placed upon the opposite piston and cylinder to unbalance the pressure to the opposite side. The required tare weights are recorded on the test log.6. Lotus spreadsheet for windows 7Weights are added to both the test unit and the master unit for the initial test point.5. Input pressure is applied to both testers with the cross-over valve in the open position.4. For the recommended procedure for leveling).3. The tester is leveled and he bulls-eye level is adjusted accordingly (See Section 4. The ball, nozzle and nozzle body of the floating ball tester with unknown effective area are thoroughly cleaned2. The calibration system incorporates a cross-over valve, a digital readout differential pressure meter and input flow meters for both the test and master testers.The procedure for calibrating the floating ball testers is as follows:1. As discussed in paragraphs 2.6.1 and 3.3, many different pressure between the output on the master and factors can contribute to wear of the piston and cylinder. M&G has many customers who have pistons and cylinders in use for over 10 years.Ametek Type T Hydraulic PumpRecertification of a deadweight tester is a precautionary measure required by each user to assure that each device has not worn sufficiently to produce inaccurate pressures. 3.3 Frequency of Calibration3.3.1 Frequency of Recertification and Recalibration of Piston & Cylinder Type Deadweight TestersThe precision piston and cylinder assembly, the operating heart of the hydraulic deadweight tester, is a device which given proper care and use has a long service life. The effective area of the unknown ball and nozzle is determined using the equation in paragraph 2.4 (AMETEK uses a proprietary computer program for this task). The steps 3 and 4 are repeated for each required test pressure.7. The pressure differential between the test andThe master tester is displayed on the differential pressure meter display.6. Tabs closed alpha download freeWe regard this as the most important single index of quality”.Confirming the NIST findings, AMETEK has found that the leakage rate of the piston and cylinder is the best measure of wear. At maximum pressure, the fall rate of a good instrument should be less than 0.1 inch per minute. Infrequently used instruments used only in laboratory conditions need not be calibrated frequently.The United States National Institute of Technology has suggested that7″For piston gages for use as plant or laboratory standards (Accuracy within 0.1%) when the gage is connected to a leak tight system and the piston is set into rotation that the piston should fall slowly as a result of the leak between it and the cylinder. If the device is exposed to heavy usage and factors that contribute to wear such as dirty instruments being tested, frequent calibration is appropriate. ![]() ![]()
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